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Royer Labs RSM-SS1 Sling-Shock Microphone Shock Mount Royer Labs RSM-SS1 Sling-Shock Microphone Shock Mount

Royer Labs RSM-SS1 Sling-Shock Microphone Shock Mount

The Royer RSM-SS1 Sling-Shock™ is a revolutionary departure from traditional shock mount designs. The Sling-Shock is hand-built in Burbank, CA facility using only the finest materials. Royer done away with the rubberized parts and elastic cords, producing a durable shock mount that gives superior isolation from vibrations.

The proprietary system of non-resonant nylon cable and damped steel springs acts to isolate the microphone from vibrations induced from the microphone stand. These vibrations can appear as rumble and/or low-grade noises which create disturbances across the bandwidth, from low end thumps to harmonic disturbances at different frequencies. The Sling-Shock's superior vibration-reduction capabilities and lack of self-resonance allow engineers to capture performances free of vibration-related interference across the bandwidth.

The Sling-Shock RSM-SS1 is sized to fit Royer's 1-inch diameter R-121, R-122, R-122V, SF-1 and SF-12 ribbon microphones. Any cylindrical microphone measuring approximately one inch in diameter (+/- 1/8 inch) will work with the model RSM-SS1. The RSM-SS24 accommodates Royer SF-2, SF-24 and SF-24V microphones.

RSM-SS1 Sling Shock Features:

  • Superior isolation from vibration and shocks
  • Felt-lined, scratch-free microphone chamber holds mic securely
  • No rubberized parts to degrade or stretch
  • Flexible for easy microphone positioning
  • Lifetime warranty

Microphone Cable Clip

Low-level vibrations can be transferred through the mic cable and into the microphone. Incorporated into the sling-shock's design is a microphone cable clip. This feature is highly effective at further reducing vibrations from being coupled to the microphone through the microphone's cable.

LIST: $295.00
PRICE: $275.00
API 505-DI 500 Series Direct Input Module API 505-DI 500 Series Direct Input Module

API 505-DI Direct Input— 500-Series Module

The distinct API sound of the console-based 205L now in the affordable, 500 series format

Designed after the console-based API 205L, the 505-DI Direct Input Module is specifically designed for guitar, bass or keyboard direct input while minimizing any loading effect on Hi-Z instrument pickups. Additionally, the 505-DI's Gain Control is used to normalize an instrument's input level, up to a +4 dBu output level. API's unique TONE control reduces potential low end "mud" in the signal, while turning on the BRIGHT switch adds additional clarity if desired. The various combinations of TONE and BRIGHT controls can eliminate the need for any EQ on the instrument while recording, keeping the signal path short and pure.

This minimal signal path eliminates the need to use a standard direct box, which many times still requires a mic input, equalizer, and a fader to get the signal to a recordable level. The 505-DI is capable of boosting any instrument to a hefty line level without additional amplifiers. Use of the 100K / 400K LOAD switch allows the tone of the pickup to be altered slightly, alternately brightening or darkening the high frequency content. When inserting an instrument with an internal preamp or a line level instrument such as a sampler or a keyboard, the 505-DI offers a 20 dB PAD switch to drop the level without loading, thereby retaining the integrity of the incoming signal.

API 505-DI Direct Input key features

  • Wide Range Gain Control with 55dB of gain
  • Front Panel Hi-Z Input
  • Front Panel Thru routing
  • TONE Control helps customize your sound
  • BRIGHT Switch boosts clarity and presence
  • 10 segment LED VU meter for monitoring output level
  • Peak Output LED Indicator
  • 20 dB pad switch, applies to mic/line/instrument
  • 100K / 400K Switchable Load
  • Traditional API fully discrete circuit design
  • Uses the famous API 2520 and 2510 Op-Amps

API 2520 Op Amp—key to the API sound

API’s 2520 Op Amp found in the 505-DI is given most of the credit for the API sound. Designed by API engineers, the 2520 is a high-gain, wide-band, direct-coupled amplifier specifically designed for audio applications. The circuit derives its characteristics mainly from the performance of its passive elements, being connected into a feedback loop, which provides predictable, stable performance. Furthermore, the discrete 10-transistor amplifier is encapsulated in a thermally conductive epoxy that protects against thermal shock, vibration, and humidity, assuring long life and reliable performance.

In total, the elegant simplicity of 2520 discrete operational amplifier provides the core of the API sound.

Don’t forget to check out RSPE’s Rack Revolution, a virtual 500-series rack builder that lets you custom-configure the perfect 500-series lunchbox for your studio, DAW, or mobile recording rig. RSPE carries every 500-series module imaginable, including mic preamps, compressor-limiters, equalizers, and 500 power racks.


API Audio's VPR Alliance

The VPR Alliance is a program of standardization and consistency guidelines for approved manufacturers wishing to design products for API's 500-series rack format. The program provides complete design specifications for manufacturers interested in producing third-party modules that physically fit and electronically conform to API's rack specifications.

The creation of the VPR Alliance was encouraged by the overwhelming popularity of API's 500-series racks, including the 10-space 500V and the six-space lunchbox®, which led to a proliferation of third party modules that fit the API format. Typically installed into API racks, these third party modules had raised issues of warranty and interaction with API-manufactured modules in the same rack.

Because of the variables related to those third party modules, API had previously been forced to declare that inserting any third-party modules into a 500V or lunchbox voided the warranty on that rack. Through the VPR Alliance, API is now able to eliminate confusion as to which third-party products definitively do and do not void the API warranty. The VPR Alliance is a straightforward resolution that saves the company time and money while promoting goodwill to API customers.

API’s customers benefit from the VPR Alliance with the knowledge of exactly which products are approved for placement in API racks; customers have a wider range of module choices for their racks that have been tested by API staff for specification compliance.

An Abbreviated History of API

It all began with a dream. It was 1968. The company: Automated Processes Inc., formed by men with a vision. Best known for their now legendary "2520 amplifier", this unique amp has been and will continue to be the heart of all API discrete products. It continues to provide reliability and sonic purity unmatched by the competition. The resulting console met the needs of the music, commercial and broadcast industry.

API became the leading audio broadcast console manufacturer for radio and television networks and high profile stations. In addition, recording studios, large and small, began using API...and receiving rave reviews from engineers and producers. There are over 700 API consoles across the nation and around the world, including the three major networks. Over thirty years later, many of these consoles are still in daily use in some of the most prestigious recording and broadcast facilities in the world because, to date, there are few, if any consoles of equal sound quality at a cost-effective price.


If you don’t have it already, there’s no time like the present to get the sound of API onto your tracks. Try RSPE’s Demo 4 Free service and find out for yourself. For more information, call or chat with an RSPE representative.


This product is also available as part of the RSPE Demo 4 Free & Rental Program, click here to see the rental product page.

LIST: $595.00
PRICE: $565.25
Miktek C1 Large Diaphragm FET Condenser Mic Miktek C1 Large Diaphragm FET Condenser Mic

Miktek C1 Large Diaphragm FET Condenser Mic

Large diaphragm FET condenser will impress the most critical listeners and inspire artists to create their best performance

The Miktek C1 large diaphragm FET condenser features a tightly controlled cardioid pick up pattern, a high-pass filter and –10dB pad for recording loud sound sources. The frequency response is warm on the bottom and silky-sweet on the top, yet at the same time, the midrange is natural and open. The microphone produces amazing results when recording acoustic instruments, guitar amps, or as overheads on a drum kit. But of course, the C1 really excels on vocal ­applications.

The C1 utilizes the new MK1 capsule developed by Miktek engineers, featuring dual 1-inch diaphragms made using 5-micron Mylar with a 0.4-micron layer of evaporated gold. The diaphragm is precisely tensioned and mounted to a carefully tuned backplate to create the finished capsule.

The C1’s head amplifier has been designed around the AMI T7 transformer and, together with the implementation of high-quality components including hand-selected transistors, offers a sweet response reminiscent of highly desirable vintage microphones.

In addition, the innovated head amplifier design features a unique circuit that allows the engineer to switch the capsule bias voltage from +44 to +60 volts. This proprietary circuit implementation essentially provides the mic with two voices; allowing you to choose between a classic and modern microphone. At +44 volts the capsule’s diaphragm is under less ­tension, so it’s able to react to extremely subtle changes in sound pressure; enabling the microphone to capture the slightest nuances in any performance. When the bias voltage is set to +60 volts, the C1 is extremely accurate and articulate.

The Miktek C1 is hand assembled, tested and packaged in Nashville, Tennessee, USA using components from the US, Europe and Asia. Each microphone includes its serialized ­frequency response graph created during final testing.

The C1 is packaged with its swivel mount, in a wooden box, along with the included shock mount.

Miktek C1 Key Features:

  • MK1 1-inch Capsule 5-micron Mylar, Evaporated Gold Diaphragm
  • Cardioid Pick-up Pattern
  • High-pass Filter & -10dB Pad Switches
  • Variable Capsule Bias Voltage: 48 – 60v
  • AMI T7 Transformer
  • Individual serialized Frequency Response Graph
  • Wood Presentation Case with Swivel-mount, Shock-mount and rugged aluminum Carrying Case

LIST: $999.00
PRICE: $599.00
Summit Audio TD-100 Instrument Preamp / DI Summit Audio TD-100 Instrument Preamp / DI

The TD-100 instrument preamp and tube direct box from Summit Audio features a hybrid signal path utilizing both a discrete transistor input device and a 12AX7A vacuum tube to give your musical instruments the clarity of class A sound with the richness and warmth of vacuum tubes all in 1/2" rack space.

This vacuum tube adds a subtle texture and smoothness, a professional sheen to your instrument, which is perfect for both live and studio use. The TD-100 offers both XLR microphone level and 1/4" TRS line level outputs, plus variable input impedance, polarity switch and ground lift, signal and overdrive LEDs, and even a headphone output for use as a practice device. See what a little Summit Audio can do for you.

PRICE: $699.99
Daking Mic Pre One Daking Mic Pre One

Daking Mic Pre One

Single channel Daking preamp featutring a Jensen transformer mic input, ¼ in DI, 70dB gain, LED meter, variable HP filter (20 to 200Hz), Discrete Class A circuitry, and outboard power supply.

The Daking Mic-Pre One is a single channel mic preamp that we originally designed with the home recordist who only needs one input in mind. Because of it’s high performance and robust mechanical design, it has also become first choice of many professionals when doing small remotes. They just throw two or three in a suitcase and off they go!

The Mic-Pre One’s great performance comes from our existing popular Daking designs, the Mic Pre EQ, Mic Pre IV, and console modules. All of these preamps use the same unique preamp circuit which features a Jensen input transformer and a Class “A” discrete transistor preamp with a single sided power supply.

The Mic-Pre One has a freestanding ‘DI-style’ aluminum enclosure, ensuring both strength and noise immunity.

Daking Mic Pre One Features:

  • 70db of gain
  • 20 segment tri color meter with VU and peak indications
  • Switchable Polarity
  • 20db pad with constant reflected impedance
  • Switchable Phantom Power
  • Direct 1/4″ instrument input on the front panel.
  • Balanced XLR Output
  • Balanced 1/4″ TRS output which can be used with unbalanced devices with no deterioration of signal.

High Pass Filter

In addition, because the home recordist faces challenges that the professional studio owner does not, the Mic-Pre One features a powerful continuously variable high-pass filter with a range of 10-200Hz @ 12db per octave

Big studios have big monitors, good isolation and quiet air conditioning. Also, if you are recording to tape at 30ips, you cannot record below 40Hz.

Small studios usually have small monitors that don’t reproduce very low frequencies well, have little or no isolation and poor ventilation. Modern digital recorders will easily record 10Hz. Because of this, many home recordings are filled with low frequency rubbish that clouds, clutters and takes up space in the mix.

The High Pass Filter in the Mic-Pre One is a powerful tool. The Filter allows the recordist to eliminate unwanted low frequency trash before it enters the signal chain without affecting the program material. This can be a giant step toward making the home record more professional.

Who’s using Daking?
“…. Over the last few years I’ve used Daking mic pres and compressors on recording for artists such as Carole King, Tracy Bonham, Jane Siberry, Hanson, Michelle Branch, Rufus Wainright, Cafe Tacuba, Julieta Venegas, Juanes and many others…” — Joe Chiccarelli

"If you're looking for that vintage sound of a Trident A Range, and you want to add warmth to the digital recording chain, look no further: the Daking mic preamps add a distinctive sonic character that really make your recordings come alive!" — Butch Vig

About Daking Audio:

Geoff Daking started his career as a drummer for the band, The Blues Magoos, who toured with The Who in the ’60s. With two hits under his belt, Daking transitioned to the other side of the glass and engineered records for artists such as Eric Clapton, Hall & Oates, Rod Stewart, Meatloaf, Steve Stills, Cat Stevens, Kenny Loggins, Cyndi Lauper, Joan Osborne, James Brown, Luther Vandross, and many more. Since the ’70s, Daking has built over 20 studios, including facilities for Cyndi Lauper, Joan Osborne, and most recently, a multi-million-dollar facility for Big3 Entertainment.

Back in 1993, audio engineers quickly realized that the new recording equipment didn’t sound nearly as good as the older gear. Geoff Daking decided to do something about it. He approached Phil Wagner at Trident (whose A-Range console designed by Malcolm Toft and Barry Porter is still considered to be the best sounding console for rock & roll) and told Wagner that if Trident produced their preamps and EQs in rackmount form, people would buy them. In turn, Wagner suggested that Daking do it, since Trident had no interest in producing such units. Proving his perceptions correct, Geoff Daking bought the original Trident schematics, borrowed a racked Trident preamp from Lenny Kravitz for reference, and the rest is history.

Using only the finest, best-sounding components, Geoff Daking’s design philosophy is based on the concept of “get home early.” That is to say, Daking products are not loaded down with unnecessary, complex features—just what you need to get the job done right and quickly. Daking Audio makes very musical, solid, high-quality equipment that is very easy to use and cost effective. It’s equally important to recognize that there’s nothing like recording equipment built by someone who not only understands how the electronics work to make the most musical sound, but also has used it to record some of the greatest artists the world has known—and that defines Daking Audio.

LIST: $849.00
PRICE: $749.00
BAE 312A Rackmount and Module BAE 312A Single Channel 500 Series Mic Pre

BAE 312A 500-Series Mic Preamp / DI

500-series compatible mic pre/DI with one of the most popular vintage sounds available: the API™ 312

The BAE 312A 500-series mic preamp is a spot-on replica of the famous API 312 preamps that populated the early API consoles. Key to the API 312’s sound was the absence of a coupling capacitor between output transformer and opamp, which allowed transients to pass easily, making it a favorite for punchy snare and toms. The early 312s owed their sound in large degree to the API 2520 opamp, which underwent numerous changes throughout the years as component manufactures discontinued lines or changed specs—but API adapted as necessary to maintain the classic 312 sound. So how does the BAE opamp compare to the original API? BAE never stops short of getting right and the Avedis 1122 opamp found in the BAE 312A takes the performance of the API 2520 opamp to a higher level. The BAE 312A gives you all the vintage punch, sound and fury that made the original 312 a classic, and adds reliable, modern performance to boot.

BAE 312A 500-Series Mic Preamp/DI features:

  • Authentic open, punchy sound of the original API 312
  • Avedis 1122 opamp improves on the performance of the 2520 opamp
  • Jensen input and output transformers
  • Switches have gold contacts for long life
  • Front-panel, Hi-Z direct input for guitar and synthesizer
  • Separate front panel switches for phantom power
  • Hand-made in the USA

Back in the ’70s there were two major players in console manufacture (three if you count Electrodyne, which disappeared early-on due to mismanagement). The Neve name inspired awe among engineers and musicians alike, and had emerged as the primary force in console making to be reckoned with. Much like John Cougar Mellencamp was signed as the American answer to David Bowie, Saul Walker’s Automated Processes Inc. (API) consoles were the American answer to Mr. Rupert Neve’s eponymous consoles. Both desks defined the sound of rock and roll in their own way, with preamps of elegant simplicity that provided the power and punch that rock and roll would continue to thrive on to this day.


Don’t forget to check out RSPE’s Rack Revolution, a virtual 500-series rack builder that lets you custom-configure the perfect 500-series lunchbox for your studio, DAW, or mobile recording rig. RSPE carries every 500-series module imaginable, including mic preamps, compressor-limiters, equalizers, and 500 power racks.


Inside the Box

Like all BAE products, the 500-series compatible BAE 312A Mic Pre/DI is made with the highest quality parts, including Jensen input and output transformers and the Avedis 1122 opamp. When discussing API preamps, the important distinction between the 312 and later 512C is the use of coupling capacitors between the output transformer and opamp. The reason for the 312’s success (it’s open punchy sound, particularly on drums) was also its greatest weakness. The 312 had no coupling capacitor between opamp and transformer. As such, if the opamp had any DC offset (a voltage output above the mean amplitude), it might burn out the transformer. The 512C had large coupling capacitor in parallel with a high-frequency capacitor and a resistor for transformer damping. The 512’s opamp also had a servo to eliminate DC offset. The result was increased headroom and the elimination of pops when the phase switch was cut in. Of course, the addition of these components led to a perceived sonic difference between the two. Those who have worked with both often hear the 312 as more open and punchy than the 512C.

To support the fast transient response of the capacitor-less 312A, the BAE 312A uses the Avedis 1122 opamp. The Avedis 1122 is a high-performance, direct-coupled operational amplifier designed specifically for professional audio amplifier applications. The 1122’s were originally made for replacement opamps in the repair of vintage API 312 and 512A mic preamps. It’s based on the same design principles as the 2520, but built with today's high-quality components, to make it operable under a wider voltage range and with lower noise than previously possible. Using no IC's, JFET's, or surface-mount components, the 1122 opamp is picks up where the 2520 left off. Its high output power, low distortion, and wide power bandwidth provides the kind of performance levels appreciated by the working professional.

Outside the Box

The front panel of the 500-series compatible BAE 312A mic pre has a matte black finish with orange BAE logo. It hosts a 1/4" Hi-Z instrument input; buttons for phase reverse, pad, and +48V phantom power; and gain knob. Your basic no-frills design, it’s what’s inside the BAE 312A that counts.

Need a lunchbox or 500-series power rack for you BAE 312A? No worries! BAE makes the 3LB 3-space lunchbox; a 6-space lunchbox and power rack; and an 11-space 500-series power rack if you’re looking to load up on vintage punch.

Who’s Using BAE:

"BAE has been an integral part of my record making for many, many years now. I have owned the mic pre's, EQ's, and racks for years. The dedication to costumer service is something one can count on. With the advent of the Avedis 1122 OpAmp, the classic 2520 opamp was brought forward into the future. Mark has also made a point at looking back at certain designs and his attention to detail shows in the new products that he is working on. I am very happy to announce and toast Mark's (Loughman) new ownership in the company. I forecast excellent things to come. — Ross Hogarth, Grammy-winning producer-engineer

"During the recording of many of the Steven Slate Drums sessions, we used lots of BAE mic pres and equalizers. They made it easy to get some of the best drum sounds I've ever heard." — Steven Slate Drums

“What all 312a users say about clarity and punch is absolutely true. They are very versatile pre amps and aside from the obvious with guitars, drums, and vocals, I really enjoy using these pre's with bass and synth sequences.” Ilan Rubin (NIN, Paramore, Lostprophets)

“I love my BAE mic pre-amp. It makes my tracks sound lovelier!” — Jane Wiedlin, The Go-Go's

“I was just screwing around with my BAE 1084 when it hit me, wonder what my Space Bass would sound like in this. I plugged it in and the sound was so pure and natural I thought I was on stage in the ‘Mothership.’ This thing sings with tone, punch, and straight-up good, solid sound that will stand out in a mix with loud drums and guitars.” – Bootsy Collins

“Two thumbs way up! In my opinion, the BAE 1073 and 1084 modules sound every bit as good as the original Neve modules I have used my whole career (we've had blind fold audio "shoot out" tests in my vintage Neve room and there is absolutely no difference). Nothing comes as close to my original Neve EQ/mic preamps as BAE products. And in my opinion, BAE products surpass all the competition in build quality; from the point-to-point wiring, to the audio traces on their cards, original St Ives (Carnhill) transformers, nickel plating, impeccable craftsmanship, and wow! —no old dirty switches and pots. (Did I mention they plugged right in to my vintage Neve 8014 frame from 1970 flawlessly!) Plus, Mark and the staff over at BAE are totally professional and a pleasure to deal with.” — Andy Kravitz, drummer, producer, engineer

Discography: (Imogen Heap, Billy Joel, The Rolling Stones, Simon Townshend, Robbie Krieger, Urge Overkill, Lizzy Grant, The Cheeters, Cypress Hill, James Taylor, Los Lobos, Soloman Burke, Joan Osborne, Taj Mahal, Mark Broussard, Norwood Fisher, Shawn Colvin, Hundred Year Flood, and Sting)

About BAE (British Audio Engineering)

Answering to a higher authority (maintaining the legacy of Mr. Rupert Neve), BAE puts nothing but the very best and their very best into every unit they built. Under the guidance of president/CEO Mark Loughman and Neve guru, Avedis Kifedjian, BAE uses the only highest quality components from the original suppliers, such as Carnhill (formerly St. Ives) and Jensen. All BAE products use discrete electronics and are completely hand-built and wired point-to point (no circuit boards). For more information about BAE, check out RSPE’s Designer’s Perspective feature and get a first-hand look at the inner workings of BAE.

Add the classic API punch to your 500-series rack with BAE’s 312A. Check out RSPE’s Rack Revolution custom 500-series module builder and get started now, or call or chat with an RSPE representative today.



This product is also available as part of the RSPE Demo 4 Free & Rental Program, click here to see the rental product page.

PRICE: $790.00
BAE 312B Signature Series Mic Pre / DI BAE 312B Signature Series Microphone Pre-Amplifier

BAE 312B Signature Series Microphone Pre-Amplifier

500-series compatible mic pre/DI with one of the most popular vintage sounds available: the API™ 312

The BAE 312B 500 Series Mic Pre / DI carries the same excellent dynamic range, frequency response and noise performance the BAE 312 series is known for, but with 9dB lower gain, making it perfect for drums or other loud instruments. BAE achieves this newly introduced and modified gain structure by utilizing a lower gain Jensen input transformer, designed to compliment louder sources before needing to implement the pad.

The 312A's higher gain structure occasionally required the pad to be used frequently with louder sources, such as a hot microphone on drums. The 312B uses an alternative Jensen transformer putting it at 7dB's of lower gain to accommodate louder sources without losing the dynamic characteristics of the 312A. This allows engineers the option of owning the 312A as a pre-amp geared toward higher gain and the 312B for toward lower gain.

The 312B, just like the 312A, features the Avedis® 1122 Discrete Op-Amp and input and output Jensen transformers which use direct-coupled circuitry with no capacitors in the signal path. The input impedance of the 312B is designed to remain consistent, even after the pad is engaged, providing a steady load to the microphone. The characteristics of the 312B offer excellent dynamic range, frequency response, high headroom, and excellent noise performance for a punchy sound which works well with many microphones.

The 312B is available as a single 500 Series module and as a fully loaded six space lunchbox. It includes a custom pull-on switch tailored to accentuate higher frequencies, a DI for instruments, a Phase Reverse switch, 48V for phantom power, and a PAD switch.

BAE 312A 500-Series Mic Preamp/DI features:

  • Made using Avedis® 1122 opamps
  • Supplied with Jensen input and output transformers.
  • Remote power supply with four-foot cable capable of four times the current needed by the preamps for optimum sound quality.
  • Switches have gold contacts for long life.
  • XLR connectors on the back for mic input and output and phone jack in front for direct input.
  • High impedance direct input for guitar and synthesizer.
  • Separate front panel switches for phantom power.


Back in the ’70s there were two major players in console manufacture (three if you count Electrodyne, which disappeared early-on due to mismanagement). The Neve name inspired awe among engineers and musicians alike, and had emerged as the primary force in console making to be reckoned with. Much like John Cougar Mellencamp was signed as the American answer to David Bowie, Saul Walker’s Automated Processes Inc. (API) consoles were the American answer to Mr. Rupert Neve’s eponymous consoles. Both desks defined the sound of rock and roll in their own way, with preamps of elegant simplicity that provided the power and punch that rock and roll would continue to thrive on to this day.

Who’s Using BAE:

"BAE has been an integral part of my record making for many, many years now. I have owned the mic pre's, EQ's, and racks for years. The dedication to costumer service is something one can count on. With the advent of the Avedis 1122 OpAmp, the classic 2520 opamp was brought forward into the future. Mark has also made a point at looking back at certain designs and his attention to detail shows in the new products that he is working on. I am very happy to announce and toast Mark's (Loughman) new ownership in the company. I forecast excellent things to come. — Ross Hogarth, Grammy-winning producer-engineer

"During the recording of many of the Steven Slate Drums sessions, we used lots of BAE mic pres and equalizers. They made it easy to get some of the best drum sounds I've ever heard." — Steven Slate Drums

“What all 312a users say about clarity and punch is absolutely true. They are very versatile pre amps and aside from the obvious with guitars, drums, and vocals, I really enjoy using these pre's with bass and synth sequences.” Ilan Rubin (NIN, Paramore, Lostprophets)

“I love my BAE mic pre-amp. It makes my tracks sound lovelier!” — Jane Wiedlin, The Go-Go's

“I was just screwing around with my BAE 1084 when it hit me, wonder what my Space Bass would sound like in this. I plugged it in and the sound was so pure and natural I thought I was on stage in the ‘Mothership.’ This thing sings with tone, punch, and straight-up good, solid sound that will stand out in a mix with loud drums and guitars.” – Bootsy Collins

“Two thumbs way up! In my opinion, the BAE 1073 and 1084 modules sound every bit as good as the original Neve modules I have used my whole career (we've had blind fold audio "shoot out" tests in my vintage Neve room and there is absolutely no difference). Nothing comes as close to my original Neve EQ/mic preamps as BAE products. And in my opinion, BAE products surpass all the competition in build quality; from the point-to-point wiring, to the audio traces on their cards, original St Ives (Carnhill) transformers, nickel plating, impeccable craftsmanship, and wow! —no old dirty switches and pots. (Did I mention they plugged right in to my vintage Neve 8014 frame from 1970 flawlessly!) Plus, Mark and the staff over at BAE are totally professional and a pleasure to deal with.” — Andy Kravitz, drummer, producer, engineer

Discography: (Imogen Heap, Billy Joel, The Rolling Stones, Simon Townshend, Robbie Krieger, Urge Overkill, Lizzy Grant, The Cheeters, Cypress Hill, James Taylor, Los Lobos, Soloman Burke, Joan Osborne, Taj Mahal, Mark Broussard, Norwood Fisher, Shawn Colvin, Hundred Year Flood, and Sting)

About BAE (British Audio Engineering)

Answering to a higher authority (maintaining the legacy of Mr. Rupert Neve), BAE puts nothing but the very best and their very best into every unit they built. Under the guidance of president/CEO Mark Loughman and Neve guru, Avedis Kifedjian, BAE uses the only highest quality components from the original suppliers, such as Carnhill (formerly St. Ives) and Jensen. All BAE products use discrete electronics and are completely hand-built and wired point-to point (no circuit boards). For more information about BAE, check out RSPE’s Designer’s Perspective feature and get a first-hand look at the inner workings of BAE.

Add the classic API punch to your 500-series rack with BAE’s 312B. Check out RSPE’s Rack Revolution custom 500-series module builder and get started now, or call or chat with an RSPE representative today.

PRICE: $790.00
A-Designs EM-Blue Preamp Module A-Designs EM-Blue 500-Series Preamp Module

A-Designs EM-Blue 500-Series Preamp Module

The A-Designs EM-Blue 500 Series Preamp Module is the brightest sounding of the EM Series, equipped with a nickel custom-wound output transformer for accentuated highs. It produces a much more airy, top-end-present tone than its EM-Series brothers and sisters. Many aspects of recording can be counter-intuitive, and in many cases, you’ll want to pair opposites. For example, when used with a dark-sounding microphone or an alto vocalist, the brighter EM-Blue can produce a heavenly sound.

You will also find this pre useful for providing a crisp “crack” when recording a snare drum. And if you use the DI you just might fall in love with what an electric guitar sounds like going thru its nickel transformers. As with all of A-Designs’ 500-Series preamps, the EM-Blue has a -20dB pad that enables you to get down and dirty with an electric guitar. Just switch in the pad and crank the gain for a slight growl.

PRICE: $795.00
A-Designs EM-Gold 500-Series Preamp Module A-Designs EM-Gold 500-Series Preamp Module

A-Designs EM-Gold 500-Series Preamp Module


The A-Designs EM-Gold 500-Series Preamp Module is a combination of EM-Silver and EM-Red transformers which makes for the perfect sounding floor tom. It’s also the preamp you should reach for when you want that speaker-moving, low-mid thump from heavy guitars.

The EM-Gold is ideal for fattening up thin-sounding sources; on mics lacking low mids or upper bass warmth; and mid transients, such as percussion and drums. It also shines on vocals, bass, and even drum machines. If you’re going to move air (the secret of a big sound), go for the Gold—the A-Designs Audio EM-Gold.

PRICE: $795.00
A-Designs EM-Red 500-Series Preamp Module A-Designs EM-Red 500-Series Preamp Module

A-Designs EM-Red 500-Series Preamp Module


The A-Designs Audio EM-Red 500-Series Preamp Module is the “mid-forward” preamp of the EM family. Its sound derives from the combination of an A-Designs proprietary input transformer featuring a unique winding, and a 50/50 steel/nickel-wound output transformer (also a proprietary A-Designs alloy).

The EM-Red has the extra kick you need when you have a mic that lacks present mids (such as the mid-scooped Chinese capsules), or if you want to bring an instrument forward in the mix. The upfront mids of the EM-Red make it ideal for drums, guitar, bass guitar, and acoustic instruments. In fact, you will find the EM-Red particularly useful when recording acoustic guitar with a condenser microphone. It’s also great for bringing out the resonance and character of rack toms and floor toms.

PRICE: $795.00
A-Designs EM-Silver 500-Series Preamp Module A-Designs EM-Silver 500-Series Preamp Module

A-Designs EM-Silver 500-Series Preamp Module


The A-Designs Audio EM-Silver 500-Series Preamp Module has a darker tone than the P-1, EM-Red, and EM-Blue. Its sound is based on a custom-wound steel output transformer, which makes it an excellent match for ribbon microphones since steel transformers were widely used in the early days of recording and broadcast. It was the combination of steel transformer and ribbon mic that gave broadcasters and singers that “voice of god” sound that has defined vocal recording and the amplified spoken word for decades.

The EM-Silver is a great preamp for bass guitar and keyboards. And in the world of percussion, it’s a great choice for kick drum. For brighter sound sources, the EM-Silver is the preamp of choice when you want less top end or a vintage-type sound. For a true vintage sound, use the EM-Silver with ribbon mics, or on modern, brighter condensers to smooth out top end. If you like vintage Neve, you’ll love the EM-Silver.

PRICE: $795.00
A-Designs P-1 500-Series Preamp Module A-Designs P-1 500-Series Preamp Module

A-Designs P-1 500-Series Preamp Module

The A-Designs P-1 500 Series Preamp Module has the highest fidelity of all the A-Designs Audio 500 preamps, capturing the mojo of its older and larger sibling, the extremely popular Pacifica. While not an exact replica, it sounds as close to Pacifica as is possible for its smaller size. It has a big low end, slightly forward midrange, and extended highs.

If you’re a fan of Quad Eight or API, you’ll love the A-Designs Audio P-1.The P-1 shines on vocals, instruments, room mics, piano, and on instruments with sharp transients, such as drums and various percussion instruments. And if you’re building a lunchbox with drum recording in mind, a pair of P-1s is a superb choice for overheads when you want to capture the entire kit along with the sizzle of the cymbals.

Don’t forget to check out RSPE’s Rack Revolution, a virtual 500-series rack builder that lets you custom-configure the perfect 500-series lunchbox for your studio, DAW, or mobile recording rig. RSPE carries every 500-series module imaginable, including mic preamps, compressor-limiters, equalizers, and 500 power racks.

LIST: $895.00
PRICE: $795.00
BAE 312A Rackmount and Module BAE 312A Single Channel Rackmount Mic Pre (no power supply)

BAE 312A Single-Channel Mic Pre/DI without Power Supply

Stunning, single-channel preamp in a 19" 1RU version delivers punch, clarity, and that famous steel-transformer API growl

The BAE 312A 500-series mic preamp is a spot-on replica of the famous API 312 preamps that populated the early API consoles. Key to the API 312’s sound was the absence of a coupling capacitor between output transformer and opamp, which allowed transients to pass easily, making it a favorite for punchy snare and toms. The early 312s owed their sound in large degree to the API 2520 opamp, which underwent numerous changes throughout the years as component manufactures discontinued lines or changed specs—but API adapted as necessary to maintain the classic 312 sound. So how does the BAE opamp compare to the original API? BAE never stops short of getting right and the Avedis 1122 opamp found in the BAE 312A takes the performance of the API 2520 opamp to a higher level. The BAE 312A gives you all the vintage punch, sound and fury that made the original 312 a classic, and adds reliable, modern performance to boot.

BAE 312A Single-Channel Mic Pre/DI features:

  • The extremely popular vintage sound of the API 312 mic preamp
  • Avedis 1122 opamp improves on the performance of the 2520 opamp
  • Jensen input and output transformers
  • Switches have gold contacts for long life
  • XLR connectors on the back for mic input and output and phone jack in front for direct input
  • High-impedance direct input for guitar and synthesizer
  • Separate front panel switches for phantom power

Back in the ’70s there were two major players in console manufacture (three if you count Electrodyne, which disappeared early-on due to mismanagement). The Neve name inspired awe among engineers and musicians alike, and had emerged as the primary force in console making to be reckoned with. Much like John Cougar Mellencamp was signed as the American answer to David Bowie, Saul Walker’s Automated Processes Inc. (API) consoles were the American answer to Mr. Rupert Neve’s eponymous consoles. Both desks defined the sound of rock and roll in their own way, with preamps of elegant simplicity that provided the power and punch that rock and roll would continue to thrive on to this day.

Inside the Box

Like all BAE products, the 500-series compatible BAE 312A Mic Pre/DI is made with the highest quality parts, including Jensen input and output transformers and the Avedis 1122 opamp. When discussing API preamps, the important distinction between the 312 and later 512C is the use of coupling capacitors between the output transformer and opamp. The reason for the 312’s success (it’s open punchy sound, particularly on drums) was also its greatest weakness. The 312 had no coupling capacitor between opamp and transformer. As such, if the opamp had any DC offset (a voltage output above the mean amplitude), it might burn out the transformer. The 512C had large coupling capacitor in parallel with a high-frequency capacitor and a resistor for transformer damping. The 512’s opamp also had a servo to eliminate DC offset. The result was increased headroom and the elimination of pops when the phase switch was cut in. Of course, the addition of these components led to a perceived sonic difference between the two. Those who have worked with both often hear the 312 as more open and punchy than the 512C.

To support the fast transient response of the capacitor-less 312A, the BAE 312A uses the Avedis 1122 opamp. The Avedis 1122 is a high-performance, direct-coupled operational amplifier designed specifically for professional audio amplifier applications. The 1122’s were originally made for replacement opamps in the repair of vintage API 312 and 512A mic preamps. It’s based on the same design principles as the 2520, but built with today's high-quality components, to make it operable under a wider voltage range and with lower noise than previously possible. Using no IC's, JFET's, or surface-mount components, the 1122 opamp is picks up where the 2520 left off. Its high output power, low distortion, and wide power bandwidth provides the kind of performance levels appreciated by the working professional.

Outside the Box

The front panel of the BAE 312A mic pre has a matte black finish with orange BAE logo. It has a 1/4" Hi-Z instrument input; buttons for phase reverse, pad, and +48V phantom power; and gain knob. Your basic no-frills design, it’s what’s inside the BAE 312A that counts.

External 24V PSU

The BAE 312A Single-Channel Mic Pre/DI requires the external BAE 24V PSU (not included) to operate. For optimal sound quality, the BAE 24V PSU provides four times the current necessary to power a preamp, and can power up to two BAE rackmount units*. While other rackmount preamps use an internal power supply, BAE chooses to go a different route in the form of an external PSU. The advantages of an external PSU are many. To begin with, not having space constraints allows BAE to design the power supply without compromise. Plus, it makes the shielding concerns of integrated power supplies a non-issue. When power supplies are built into the same chassis as the audio circuitry, nearby audio paths are susceptible to nasty magnetic fields radiated from the transformers, which adds noise and hum. Additionally, the preamp’s components are subject to extra heat generated from transformers, regulators, and rectifiers—and as we all know, heat is the enemy of electronics. It causes unwanted changes in operational parameters and premature component failure.

Since the BAE 24V PSU can power up to two BAE units, the BAE 312A comes with and without power supply in case you already have a BAE unit and power supply. (For BAE 312A with power supply, see BAE 312A Single + PSU and BAE 312A Dual + PSU)

Who’s Using BAE:

"BAE has been an integral part of my record making for many, many years now. I have owned the mic pre's, EQ's, and racks for years. The dedication to costumer service is something one can count on. With the advent of the Avedis 1122 OpAmp, the classic 2520 opamp was brought forward into the future. Mark has also made a point at looking back at certain designs and his attention to detail shows in the new products that he is working on. I am very happy to announce and toast Mark's (Loughman) new ownership in the company. I forecast excellent things to come. — Ross Hogarth, Grammy-winning producer-engineer

"During the recording of many of the Steven Slate Drums sessions, we used lots of BAE mic pres and equalizers. They made it easy to get some of the best drum sounds I've ever heard." — Steven Slate Drums

“What all 312a users say about clarity and punch is absolutely true. They are very versatile pre amps and aside from the obvious with guitars, drums, and vocals, I really enjoy using these pre's with bass and synth sequences.” Ilan Rubin (NIN, Paramore, Lostprophets)

“I love my BAE mic pre-amp. It makes my tracks sound lovelier!” — Jane Wiedlin, The Go-Go's

“I was just screwing around with my BAE 1084 when it hit me, wonder what my Space Bass would sound like in this. I plugged it in and the sound was so pure and natural I thought I was on stage in the ‘Mothership.’ This thing sings with tone, punch, and straight-up good, solid sound that will stand out in a mix with loud drums and guitars.” – Bootsy Collins

“Two thumbs way up! In my opinion, the BAE 1073 and 1084 modules sound every bit as good as the original Neve modules I have used my whole career (we've had blind fold audio "shoot out" tests in my vintage Neve room and there is absolutely no difference). Nothing comes as close to my original Neve EQ/mic preamps as BAE products. And in my opinion, BAE products surpass all the competition in build quality; from the point-to-point wiring, to the audio traces on their cards, original St Ives (Carnhill) transformers, nickel plating, impeccable craftsmanship, and wow! —no old dirty switches and pots. (Did I mention they plugged right in to my vintage Neve 8014 frame from 1970 flawlessly!) Plus, Mark and the staff over at BAE are totally professional and a pleasure to deal with.” — Andy Kravitz, drummer, producer, engineer

Discography: (Imogen Heap, Billy Joel, The Rolling Stones, Simon Townshend, Robbie Krieger, Urge Overkill, Lizzy Grant, The Cheeters, Cypress Hill, James Taylor, Los Lobos, Soloman Burke, Joan Osborne, Taj Mahal, Mark Broussard, Norwood Fisher, Shawn Colvin, Hundred Year Flood, and Sting)

About BAE (British Audio Engineering)

Answering to a higher authority (maintaining the legacy of Mr. Rupert Neve), BAE puts nothing but the very best and their very best into every unit they built. Under the guidance of president/CEO Mark Loughman and Neve guru, Avedis Kifedjian, BAE uses the only highest quality components from the original suppliers, such as Carnhill (formerly St. Ives) and Jensen. All BAE products use discrete electronics and are completely hand-built and wired point-to point (no circuit boards). For more information about BAE, check out RSPE’s Designer’s Perspective feature and get a first-hand look at the inner workings of BAE.

Add the classic API growl and punch to your recordings with BAE’s single-channel 312A Mic Pre/DI. Call or chat with an RSPE representative today.

PRICE: $800.00
BAE G10 500-Series Graphic EQ BAE G10 500-Series Graphic EQ

BAE G10 500-Series Graphic EQ

A 500 series equalizer from BAE, the masters of recreating vintage sound with modern features and components.

The BAE G10 500-Series 10-Band Equalizer features a Balanced Input and Output and Hi/Low-Pass Filters, making it the Ultimate Hands-On Sound Shaping Tool for Tracking, Mixing, or Mastering.

The G10 combines a punchy, transformer-based signal path with the versatile 10-band graphic EQ configuration and a 2520 style op-amp — making it ideal for tweaking drum or guitar sounds, or even processing an entire mix.

With 10 carefully selected bands offering up to 12 dB of boost or cut on tap, the G10 offers a level of tone sculpting that can help any audio sit perfectly in the mix. The easy-to-use slider-based interface helps users intuitively visualize the EQ curves they are applying. Switchable high-pass and low-pass filters, tuned at 80 Hz and 12 kHz respectively, help make the G10 a truly complete sound shaping solution.

The BAE Audio G10 implements a classic op-amp like those used in well-loved ‘70s American mixing boards. Unlike some other 10-band equalizers presently on the market, the G10 is fully transformer balanced on the input and output, and features a CineMag transformer, to give any audio passing through a unique tonal character.


BAE G10 500-Series Graphic EQ features:

  • CineMag transformer balanced in/out
  • Hand-built in the USA using top quality components throughout
  • +/- 12dB Boost/Cut @ 31Hz, 63Hz,125Hz, 250Hz, 500Hz, 1KHz, 2KHz, 4KHz, 8KHz, 16KHz
  • Individually Selectable LPF @ 12KHz, and HPF @ 80Hz (approx. 6 and 10 dB per octave, respectively)
  • EQ In/Out Select Switch (bypasses EQ and Filters)
  • Fully enclosed ventilated steel enclosure

Don’t forget to check out RSPE’s Rack Revolution, a virtual 500-series rack builder that lets you custom-configure the perfect 500-series lunchbox for your studio, DAW, or mobile recording rig. RSPE carries every 500-series module imaginable, including mic preamps, compressor-limiters, equalizers, and 500 power racks.


Who’s Using BAE:

"BAE has been an integral part of my record making for many, many years now. I have owned the mic pre's, EQ's, and racks for years. The dedication to costumer service is something one can count on. With the advent of the Avedis 1122 OpAmp, the classic 2520 opamp was brought forward into the future. Mark has also made a point at looking back at certain designs and his attention to detail shows in the new products that he is working on. I am very happy to announce and toast Mark's (Loughman) new ownership in the company. I forecast excellent things to come. — Ross Hogarth, Grammy-winning producer-engineer

"During the recording of many of the Steven Slate Drums sessions, we used lots of BAE mic pres and equalizers. They made it easy to get some of the best drum sounds I've ever heard." — Steven Slate Drums

“What all 312a users say about clarity and punch is absolutely true. They are very versatile pre amps and aside from the obvious with guitars, drums, and vocals, I really enjoy using these pre's with bass and synth sequences.” Ilan Rubin (NIN, Paramore, Lostprophets)

“I love my BAE mic pre-amp. It makes my tracks sound lovelier!” — Jane Wiedlin, The Go-Go's

“I was just screwing around with my BAE 1084 when it hit me, wonder what my Space Bass would sound like in this. I plugged it in and the sound was so pure and natural I thought I was on stage in the ‘Mothership.’ This thing sings with tone, punch, and straight-up good, solid sound that will stand out in a mix with loud drums and guitars.” – Bootsy Collins

“Two thumbs way up! In my opinion, the BAE 1073 and 1084 modules sound every bit as good as the original Neve modules I have used my whole career (we've had blind fold audio "shoot out" tests in my vintage Neve room and there is absolutely no difference). Nothing comes as close to my original Neve EQ/mic preamps as BAE products. And in my opinion, BAE products surpass all the competition in build quality; from the point-to-point wiring, to the audio traces on their cards, original St Ives (Carnhill) transformers, nickel plating, impeccable craftsmanship, and wow! —no old dirty switches and pots. (Did I mention they plugged right in to my vintage Neve 8014 frame from 1970 flawlessly!) Plus, Mark and the staff over at BAE are totally professional and a pleasure to deal with.” — Andy Kravitz, drummer, producer, engineer

Discography: (Imogen Heap, Billy Joel, The Rolling Stones, Simon Townshend, Robbie Krieger, Urge Overkill, Lizzy Grant, The Cheeters, Cypress Hill, James Taylor, Los Lobos, Soloman Burke, Joan Osborne, Taj Mahal, Mark Broussard, Norwood Fisher, Shawn Colvin, Hundred Year Flood, and Sting)

About BAE (British Audio Engineering)

Answering to a higher authority (maintaining the legacy of Mr. Rupert Neve), BAE puts nothing but the very best and their very best into every unit they built. Under the guidance of president/CEO Mark Loughman and Neve guru, Avedis Kifedjian, BAE uses the only highest quality components from the original suppliers, such as Carnhill (formerly St. Ives) and Jensen. All BAE products use discrete electronics and are completely hand-built and wired point-to point (no circuit boards). For more information about BAE, check out RSPE’s Designer’s Perspective feature and get a first-hand look at the inner workings of BAE.


Add clean vintage sound and versatility of a 10-band Graphic EQ to your 500 Series rack with the BAE G10. Check out RSPE’s Rack Revolution custom 500-series module builder and get started now, or call or chat with an RSPE representative today.

PRICE: $850.00
API 512c Discrete Mic / Line Pre API 512c Discrete Mic / Line Pre

API 512c Discrete Mic/Line Pre — 500-Series Module

The distinct API sound at an extremely affordable price

API 512 preamps are most noted for their punch and clarity. The API 512c, first introduced in the ’70s, was an advancement of the original 512. Today’s 500-series API 512c preamp remains faithful to the original circuit designs of API's founder, Saul Walker. Full-featured and still hand assembled, the API 512c carefully preserves the original sound character that made API a prominent figure in the early days of recording. API innovated the modular approach to console building, plus the format and specs for the 500 series. API preamps and EQs have been used to create some of the most famous custom consoles, such as the API/De Medio console at Sunset Sound, responsible for seminal recordings by artists such as Van Halen, Crosby Stills & Nash, and the Rolling Stones, to name but a few. Offering high headroom and a wide variety of inputs and input access points, the API 512c excels on drums, percussion, guitars, and vocals.

API 512c Discrete Mic / Line Pre key features

  • Mic preamp with 65dB gain
  • Front- and rear-panel mic input access
  • Line/instrument preamp with 45dB gain
  • Front-panel line/instrument input
  • LED VU meter for monitoring output level
  • 20dB pad switch, applies to mic/line/instrument
  • 48V switchable phantom power
  • Proprietary API fully discrete circuit design
  • Uses the famous API 2520 Op-Amp

Don’t forget to check out RSPE’s Rack Revolution, a virtual 500-series rack builder that lets you custom-configure the perfect 500-series lunchbox for your studio, DAW, or mobile recording rig. RSPE carries every 500-series module imaginable, including mic preamps, compressor-limiters, equalizers, and 500 power racks.


API 512c — Inside The Box

The API 512b and 512c were next-generation versions of the original 512, which was the first modular mic preamp made. What differentiated the 512 from the earlier 312 were two major factors. First, the 312 was a mic preamp card used in the early consoles, whereas the 512 was a modular design that featured all controls and functions on the front panel. Secondly, the 312 had no coupling capacitor between the output transformer and the op amp, which meant if there was any DC offset in the op amp, it could likely fry the transformer. To rectify this, API designed the 512c with a large coupling capacitor in parallel with a high-frequency capacitor, which in turn was in parallel with a resistor for transformer damping. Also, the 2520 op amp was given a servo to eliminate offset, which resulted in two things: increased headroom and the elimination of popping caused by the phase button being switched in and out of the circuit.

API 2520 Op Amp and 2503 transformer—key to the API sound

API’s 2520 Op Amp found in the 512c is given most of the credit for the API sound. Designed by API engineers, the 2520 is a high-gain, wide-band, direct-coupled amplifier specifically designed for audio applications. The circuit derives its characteristics mainly from the performance of its passive elements, being connected into a feedback loop, which provides predictable, stable performance. Furthermore, the discrete 10-transistor amplifier is encapsulated in a thermally conductive epoxy that protects against thermal shock, vibration, and humidity, assuring long life and reliable performance.

Another contributor to the API sound is the 2503 output transformer. Since the mid seventies, the API 2503 output transformer has gone through a number of iterations in an effort to get back to the original sound. The reason for the change in the sound of the output transformers was a mystery for many years—a mystery finally solved by former API owner, Paul Wolff in 1997.

According to Paul, the process for winding output transformers back in the early days was unknown to most manufacturers because they never specified it. The winding process was simply a part of the transformer maker’s procedure. They used a ribbon-like wire, where all four windings were done at once to save time and money. However, in later times, when trying to recreate the original sound of the 2503, the lacquer used to glue the windings together turned to powder, so no one could see the old process, or figure out why the old transformers sounded so good, whereas the new ones had an 80kHz peak, which extended down into audible range making the transformer sound brighter. Apparently, in the middle ’70s, and unbeknownst to most manufacturers, the ribbon wire had disappeared from use and subsequent transformers were wound from four separate spools of wire, which caused inconsistent wrapping, hence the high-frequency peak.

By 1997 the winding problem was finally identified and the experimentation to return to the former glory of the 2503 began. The solution was a type of wire called Litz wire, which comprises multiple strands of wires electrically insulated form one another, twisted together in a prescribed pattern, and then wound around the bobbin. Litz wire reduces skin effect, which causes resistance to increase at high frequencies, and proximity effect, which causes power losses at high frequencies. Litz wire is very effective up to 500kHz and ultimately produced the same effect as the ribbon wire with identical sonic results. This 10-year odyssey of discovery is why the new API 2503 transformer is virtually an exact match to the old API 2503.

In total, the elegant simplicity of 2520 discrete operational amplifier combined with the 2503 output transformer provides the core of the API sound, yielding one of the most sought-after mic preamps ever designed.

API 512c — Outside The Box

On API 512c front panel is a 7-segment LED VU meter next to a continuous gain control that provides 34dB to 65dB of low noise (-129 EIN) gain. Among the 512c’s front-panel controls are a 48V Phantom Power switch; Polarity switch, that reverses the output phase 180 degrees; -20dB Pad that controls both mic and line input; Mic or Hi-Z Instrument/Line selector, and ¼" Hi-Z Line input. Front-panel XLR and ¼" connectors combined with rear panel mic access allow for additional flexibility when installed into an API lunchbox, API 10-position 500V vertical rack, or an API console.

API Audio's VPR Alliance

The VPR Alliance is a program of standardization and consistency guidelines for approved manufacturers wishing to design products for API's 500-series rack format. The program provides complete design specifications for manufacturers interested in producing third-party modules that physically fit and electronically conform to API's rack specifications.

The creation of the VPR Alliance was encouraged by the overwhelming popularity of API's 500-series racks, including the 10-space 500V and the six-space lunchbox®, which led to a proliferation of third party modules that fit the API format. Typically installed into API racks, these third party modules had raised issues of warranty and interaction with API-manufactured modules in the same rack.

Because of the variables related to those third party modules, API had previously been forced to declare that inserting any third-party modules into a 500V or lunchbox voided the warranty on that rack. Through the VPR Alliance, API is now able to eliminate confusion as to which third-party products definitively do and do not void the API warranty. The VPR Alliance is a straightforward resolution that saves the company time and money while promoting goodwill to API customers.

API’s customers benefit from the VPR Alliance with the knowledge of exactly which products are approved for placement in API racks; customers have a wider range of module choices for their racks that have been tested by API staff for specification compliance.

An Abbreviated History of API

It all began with a dream. It was 1968. The company: Automated Processes Inc., formed by men with a vision. Best known for their now legendary "2520 amplifier", this unique amp has been and will continue to be the heart of all API discrete products. It continues to provide reliability and sonic purity unmatched by the competition. The resulting console met the needs of the music, commercial and broadcast industry.

API became the leading audio broadcast console manufacturer for radio and television networks and high profile stations. In addition, recording studios, large and small, began using API...and receiving rave reviews from engineers and producers. There are over 700 API consoles across the nation and around the world, including the three major networks. Over thirty years later, many of these consoles are still in daily use in some of the most prestigious recording and broadcast facilities in the world because, to date, there are few, if any consoles of equal sound quality at a cost-effective price.

If you don’t have it already, there’s no time like the present to get the sound of API onto your tracks. Try RSPE’s Demo 4 Free service and find out for yourself. For more information, call or chat with an RSPE representative.


This product is also available as part of the RSPE Demo 4 Free & Rental Program, click here to see the rental product page.

LIST: $895.00
PRICE: $850.25
Miktek C7e Large Diaphragm Multi-Pattern FET Condenser Mic Miktek C7e Large Diaphragm Multi-Pattern FET Condenser Mic

Miktek C7e Large Diaphragm Multi-Pattern FET Condenser Mic

Large diaphragm FET condenser microphone with selectable polar patterns, high pass filter and -10dB pad

The Miktek C7e, multi-pattern, large diaphragm FET condenser will impress the most critical listeners and inspire artists to create their best performance. The microphone’s pick-up characteristic is selectable; offering cardioid, omni and bidirectional patterns. In addition, the C7e employs a high-pass filter and –10dB pad for recording loud sound sources.

The frequency response is warm on the bottom and silky-sweet on the top, yet at the same time, the midrange is natural and open. The microphone produces amazing results when recording acoustic instruments, guitar amps, or as overheads on a drum kit. But of course, the C7 really excels on vocal applications.

The C7e utilizes the new MK7 capsule developed by Miktek engineers, featuring dual 1-inch diaphragms made using 5-micron Mylar with a 0.4-micron layer of evaporated gold. Diaphragms are then precisely tensioned, mounted to carefully- tuned backplates, and finally set back-to-back, with electronic isolation, to create the finished capsule.

The C7e’s head amplifier has been designed around the AMI T7 transformer and, together with the implementation of high-quality components including hand-selected transistors, offers a sweet response reminiscent of highly desirable vintage microphones.

In addition, the innovated head amplifier design features a unique circuit that allows the engineer to switch the capsule bias voltage from +44 to +60 volts. This proprietary circuit implementation essentially provides the mic with two voices; allowing you to choose between a classic and modern microphone. At +44 volts the capsule’s diaphragm is under less tension, so it’s able to react to extremely subtle changes in sound pressure; enabling the microphone to capture the slightest nuances in any performance. When the bias voltage is set to +60 volts, the C7e is extremely accurate and articulate.

The Miktek C7e is hand assembled, tested and packaged in Nashville, Tennessee, USA using components from the US, Europe and Asia. Each microphone includes its serialized frequency response graph created during final testing.

The C7e is packaged with its swivel mount, in a wooden box, and set inside a rugged aluminum case along with the included shock mount.

Miktek C7e Key Features:

  • MK7 Dual 1-inch Capsule 5-micron Mylar, Evaporated Gold Diaphragms
  • Cardioid, Omni and Bidirectional Pick-up Patterns
  • High-pass Filter & -10dB Pad Switches
  • Variable Capsule Bias Voltage: 48 – 60v
  • AMI T7 Transformer
  • Individual serialized Frequency Response Graph
  • Wood Presentation Case with Swivel-mount, Shock-mount and rugged aluminum Carrying Case
  • Shipping Dims : 14” x 14” x 7” Shipping Weights:

LIST: $1,499.00
PRICE: $899.00
Summit Audio TLA-50 Tube Leveling Amplifier / Compressor Summit Audio TLA-50 Tube Leveling Amplifier / Compressor

The Summit Audio Tube Leveling Amplifier is a hybrid of technologies.  It contains both vacuum tube and solid state components.

This combination of old and new technology produces an incredibly warm and smooth sounding compression device without the inherent disadvantages of the older designs.

PRICE: $899.99
Summit Audio 2BA-221 Mic/Line Preamp Summit Audio 2BA-221 Mic/Line Preamp

Introducing the extraordinary 2BA-221 Mic and Line Module, featuring our remarkable continuously variable impedance microphone preamp. With microphone level, line level, and Hi-Z instrument inputs, the 2BA-221 utilizes separate and individually controlled solid state input controls to mix the microphone input with the Hi-Z or line input into the variable vacuum tube output. Using the variable mic impedance and variable solid state and tube stages gives you unprecedented sonic control of anything you throw at it, be it mic level, line level, or instrument level.

PRICE: $899.99
BAE 500C FET Compressor BAE 500C FET Compressor

BAE 500C FET Compressor 500 Series Module

500-series compatible FET compressor that's robust and musical.

Based on the design of studio staple FET compressors of the ’60s and ’70s heard on countless hit records, the 500C features controls for input and output gain, plus the four selectable, time-honored compression rations of 4:1, 8:1, 12:1, and 20:1.

In addition to taming peaks, its premium components and classic circuit design add highly desireable analog warmth to your signal, making it an all-star for everything from drums to bass to vocals. Like all BAE Audio gear, the 500C is hand-wired in California to ensure the highest possible quality control.

BAE 500C features:

  • FET gain reduction
  • Three 2520 style opamps
  • Transformer coupled output
  • Feedback style peak limiter
  • SC HPF
  • Hard bypass
  • Gain Reduction on/off
  • Comp ratios: 2:1, 4:1, 8:1, 12:1, 20:1, ABI
  • ABI All Buttons In
  • Fully enclosed
  • High quality components throughout
  • Hand-made in the USA

Don’t forget to check out RSPE’s Rack Revolution, a virtual 500-series rack builder that lets you custom-configure the perfect 500-series lunchbox for your studio, DAW, or mobile recording rig. RSPE carries every 500-series module imaginable, including mic preamps, compressor-limiters, equalizers, and 500 power racks.


Who’s Using BAE:

"BAE has been an integral part of my record making for many, many years now. I have owned the mic pre's, EQ's, and racks for years. The dedication to costumer service is something one can count on. With the advent of the Avedis 1122 OpAmp, the classic 2520 opamp was brought forward into the future. Mark has also made a point at looking back at certain designs and his attention to detail shows in the new products that he is working on. I am very happy to announce and toast Mark's (Loughman) new ownership in the company. I forecast excellent things to come. — Ross Hogarth, Grammy-winning producer-engineer

"During the recording of many of the Steven Slate Drums sessions, we used lots of BAE mic pres and equalizers. They made it easy to get some of the best drum sounds I've ever heard." — Steven Slate Drums

“What all 312a users say about clarity and punch is absolutely true. They are very versatile pre amps and aside from the obvious with guitars, drums, and vocals, I really enjoy using these pre's with bass and synth sequences.” Ilan Rubin (NIN, Paramore, Lostprophets)

“I love my BAE mic pre-amp. It makes my tracks sound lovelier!” — Jane Wiedlin, The Go-Go's

“I was just screwing around with my BAE 1084 when it hit me, wonder what my Space Bass would sound like in this. I plugged it in and the sound was so pure and natural I thought I was on stage in the ‘Mothership.’ This thing sings with tone, punch, and straight-up good, solid sound that will stand out in a mix with loud drums and guitars.” – Bootsy Collins

“Two thumbs way up! In my opinion, the BAE 1073 and 1084 modules sound every bit as good as the original Neve modules I have used my whole career (we've had blind fold audio "shoot out" tests in my vintage Neve room and there is absolutely no difference). Nothing comes as close to my original Neve EQ/mic preamps as BAE products. And in my opinion, BAE products surpass all the competition in build quality; from the point-to-point wiring, to the audio traces on their cards, original St Ives (Carnhill) transformers, nickel plating, impeccable craftsmanship, and wow! —no old dirty switches and pots. (Did I mention they plugged right in to my vintage Neve 8014 frame from 1970 flawlessly!) Plus, Mark and the staff over at BAE are totally professional and a pleasure to deal with.” — Andy Kravitz, drummer, producer, engineer

Discography: (Imogen Heap, Billy Joel, The Rolling Stones, Simon Townshend, Robbie Krieger, Urge Overkill, Lizzy Grant, The Cheeters, Cypress Hill, James Taylor, Los Lobos, Soloman Burke, Joan Osborne, Taj Mahal, Mark Broussard, Norwood Fisher, Shawn Colvin, Hundred Year Flood, and Sting)

About BAE (British Audio Engineering)

Answering to a higher authority (maintaining the legacy of Mr. Rupert Neve), BAE puts nothing but the very best and their very best into every unit they built. Under the guidance of president/CEO Mark Loughman and Neve guru, Avedis Kifedjian, BAE uses the only highest quality components from the original suppliers, such as Carnhill (formerly St. Ives) and Jensen. All BAE products use discrete electronics and are completely hand-built and wired point-to point (no circuit boards). For more information about BAE, check out RSPE’s Designer’s Perspective feature and get a first-hand look at the inner workings of BAE.

Add classic FET compression to your 500-series rack with BAE’s 500C. Check out RSPE’s Rack Revolution custom 500-series module builder and get started now, or call or chat with an RSPE representative today.

PRICE: $950.00
Sunset Sound S1P Tutti 500 Series Discrete Mic Pre Sunset Sound S1P Tutti 500 Series Discrete Mic Pre

Sunset Sound S1P Tutti – 500 Series Preamp

A 500-series issue of the preamps found in the custom API consoles at Sunset Sound Studios.

If the name Sunset Sound S1P Tutti rings familiar, that’s because the Sunset Sound in question is none other than Hollywood’s famous Sunset Sound recording studio. And “Tutti” in this case does not mean full orchestra; rather it pays homage to Sunset’s founder, Tutti Camarata. The Sunset Sound S1P Tutti is a 500-series mic/instrument preamp that celebrates 50 years of recordings, including albums by The Doors, Van Halen, Sheryl Crow, Led Zeppelin, and the Wallflowers. Famous for its vocal-recording quality, the S1P is based on the preamp used in the massive API console in Studio A where so many famous vocalists have recorded.
The Sunset Sound S1P uses dual Hardy 990 op amps and two custom-made Cinemag nickel transformers (in-out) built to the same specifications as the originals made by Ed Reichenbach, father of Cinemag’s Tom Reichenbach. Before the release of the S1P preamp, the only way to get that custom API-De Medio preamp sound was to record at Sunset Sound. Thanks to the S1P’s modular 500-series format, Sunset Sound comes to you.

Sunset Sound S1P Tutti unique features:

  • Same design used in the Sunset API/De Medio consoles
  • Dual Hardy 990 op-amps
  • Custom Cinemag nickel transformers

Sunset Sound S1P Tutti key features:

  • Greater than 60dB of Gain
  • 10Hz to 60kHz FLAT
  • Distortion less than .02%
  • Clips at +28dBu
  • Signal/overload Indicator
  • Selectable input gain, 10dB steps
  • Adjustable gain trim, +/- 6dB
  • Output fader control
  • Front and Rear XLR Mic input
  • Hi-Z/INST front-panel input
  • Made in the USA

Don’t forget to check out RSPE’s Rack Revolution, a virtual 500-series rack builder that lets you custom-configure the perfect 500-series lunchbox for your studio, DAW, or mobile recording rig. RSPE carries every 500-series module imaginable, including mic preamps, compressor-limiters, equalizers, and 500 power racks.


INSIDE THE BOX — Sunset Sound S1P Tutti Preamp

In the early days of Sunset Sound, there were no commercial consoles available. All recording studio consoles were custom made. Designers such as Dean Jensen, Frank De Medio, Eric Benton, and Bob Bushnell were kept pretty busy in LA designing custom consoles using Saul Walker’s API modules. Custom API consoles were built for recording facilities such as CBS in-house studios, Fox sound stages, Sunset Sound, Hollywood Sound Recorders, and Oceanway Studios, to name a few. Many of these consoles are still in use today, including the two custom API consoles designed by Frank De Medio, Eric Benton, and Deane Jensen at Sunset Sound.

It is from these consoles that spring the Sunset Sound S1P “Tutti” 50th Anniversary preamp. The Sunset Sound S1P Tutti mic/line preamp is 100% discrete and draws less than 100ma, making it quite friendly with 500-series power racks. It features components such as the Hardy 990 discrete op-amp, considered to be the finest op-amp available for audio applications. The Hardy 990 is based on the original 990 designed by Deane Jensen of Jensen Transformers, for he was awarded a patent. The Hardy 990 offers several important changes and improvements over the original Jensen design.

The Sunset Sound S1P also features the same custom transformers built by Ed Reichenbach, whose son, Tom, founded Cinemag, the company that built the custom transformers currently found in the S1P.

OUTSIDE THE BOX — Sunset Sound S1P Tutti Preamp

The sunset gold faceplate of the 500-series S1P “Tutti” mic/instrument preamp features the following controls, including Gain from 10-60dB, ±6dB trim; a fader-like rotary output that allows you to hit the preamp hard for a thicker, more aggressive sound and adjust output to prevent distorting ADAs; a front-panel XLR/1/4" input for mic, line, or instrument; plus phase reverse and phantom power.

Who’s using Sunset Sound:

Perhaps it would be more accurate to say, who’s recorded at Sunset Sound and used the console preamps:

Studio 1: Van Halen, Paul McCartney, James Taylor, Macy Gray, Bee Gees, Doobie Bros., Whitney Houston, Barry Manilow, Oingo Boingo, Luis Miguel, Rolling Stones, Dave Grusin, Crosby, Stills, Nash, Lee Ritenour, Fourplay, Richard Thompson, Yes, Brian Wilson, Beach Boys, Annette Funicello, Carly Simon, Miles Davis, Louis Armstrong, Bangles, Fishbone, Randy Newman, Sly & Family Stone, “Fabulous Baker Boys”, Vonda Shepard, Tom Petty, “The Firm”, Sheena Easton, Patti Austin, Aaron Neville, “Mary Poppins”, Sam Cooke, The Turtles, “101 Dalmations”, Lovin» Spoonful, Buffalo Springfield, Janis Joplin, Genesis, Kenny Loggins, Jackson Browne, “My Best Friend»s Wedding”, Reel Big Fish, “Dr. Doolittle”, “The Truman Show”, and “Tootsie”

Studio 2: Van Halen, Led Zeppelin IV, Sheryl Crow, Smashing Pumpkins, Matthew Sweet, Ringo Starr, Elton John, Celine Dion, Earl Klugh, Alanis Morrisette, Michael Jackson, Toto, Lita Ford, Robert Palmer, “Dick Tracy”, “Dune”, “Days Of Thunder”, “Rocky II & IV”, Ry Cooder, Richard Marx, Aretha Franklin, Tom Waits, Neil Young, Crowded House, Bob Dylan, Jennifer Holliday, Olivia Newton-John, Melissa Manchester, Barbra Streisand, Roberta Flack, Rick James, “Major League”, “Great Balls Of Fire”, Michael Feinstein, “Wayne»s World”, “Wayne»s World II”, Alice Cooper (Muscle »73), Leo Sayer, “The Waterboy”, “The Big Lebowski”, “Pleasantville”, Doyle Bramhall, Weezer, “The Prince Of Egypt”, DDT, Poison, and Andy Williams

Studio 3: The Surfers, Elliott Smith, Social Distortion, Sugar Ray, Mary Lou Lord, “Midnight In The Garden Of Good & Evil”, Earth Wind & Fire, Prince, Dan Fogelberg, Hiroshima, Rancid, k d lang, The Wallflowers, Beck, Mr. Mister, Stevie Nicks, Belinda Carlisle, Kix, Desert Rose Band, Air Supply, Counting Crows, Deborah Harry, Jody Watley, Neil Diamond, Rita Coolidge, Lionel Ritchie, Sam Phillips, Fleetwood Mac, Tom Jones, Van Dyke Parks, Gillian Welch, The Refreshments, Dolly Parton, Kenny Rogers, Thisway, and Melissa Etheridge

Convinced?

About Sunset Sound

“Why would I want to own a studio,” Walt Disney responded to the suggestion of his company’s director of recording Tutti Camarata. “I’d rather be a client.” Was this gentle Walt’s way of asking his music man to seek employment elsewhere, or a subtle nudge to encourage entrepreneurship? Tutti presumed the latter, and so it began. It was a perfect little brick structure, once an automotive repair garage. The walls, ceiling, and floor all slanted toward one corner of the cavern where the excess automobile fluids trickled into a drain. Non-parallel surfaces are ideal for acoustic control—and ideal for a studio! Tutti kicked the tires a few times and declared, “I’ll take it!” Little did he know that the small step he took in 1958 on Sunset Boulevard in Hollywood would soon be joined by the stampede of giants.

If you can’t go to Sunset Sound, let Sunset Sound come to your studio—put an S1P Tutti preamp or two in your 500-series rack. For more information, call or chat with an RSPE representative today.

LIST: $1,599.00
PRICE: $995.00
Blue Microphones Robbie Mic Preamp Blue Microphones Robbie Mic Preamp

Complete the Circuit

Simplicity of design. Purity of sound. Robbie is Blue's Class-A discrete tube microphone and instrument preamplifier. All of the technical quality and design innovation that goes into their line of award-winning microphones has been engineered into making Robbie the finest tube preamp available today. With no ICs and only the highest-quality discrete components from input to output, Robbie is one of the quietest (-131 dB EIN @ 50 ohms) and most detailed (THD 0.006%) tube preamps available today. It features audiophile-grade ultra low noise metal film resistors and polystyrene capacitors, and provides the user with the best of both worlds: an electronically-balanced, fully discrete input stage, tube gain stage (ECC88 twin triode), and an electronically-balanced solid-state output stage. There is no switching crossover distortion anywhere in the completely balanced audio signal path. And if that's not enough, Robbie achieves and amazing 34dB headroom before clipping! Designed from the ground up, this limited production mic pre is like nothing else commercially available today.

PRICE: $999.99
BAE 312A Single Channel Microphone Preamp with Power Supply BAE 312A Single Channel Microphone Preamp with Power Supply

BAE 312A Single-Channel Mic Pre/DI with Power Supply

Stunning, single-channel preamp in a 19" 1RU version delivers punch, clarity, and that famous steel-transformer API growl

The BAE 312A 500-series mic preamp is a spot-on replica of the famous API 312 preamps that populated the early API consoles. Key to the API 312’s sound was the absence of a coupling capacitor between output transformer and opamp, which allowed transients to pass easily, making it a favorite for punchy snare and toms. The early 312s owed their sound in large degree to the API 2520 opamp, which underwent numerous changes throughout the years as component manufactures discontinued lines or changed specs—but API adapted as necessary to maintain the classic 312 sound. So how does the BAE opamp compare to the original API? BAE never stops short of getting right and the Avedis 1122 opamp found in the BAE 312A takes the performance of the API 2520 opamp to a higher level. The BAE 312A gives you all the vintage punch, sound and fury that made the original 312 a classic, and adds reliable, modern performance to boot.

BAE 312A Single-Channel Mic Pre/DI features:

  • The extremely popular vintage sound of the API 312 mic preamp
  • Avedis 1122 opamp improves on the performance of the 2520 opamp
  • Jensen input and output transformers
  • Switches have gold contacts for long life
  • XLR connectors on the back for mic input and output and phone jack in front for direct input
  • High-impedance direct input for guitar and synthesizer
  • Separate front panel switches for phantom power
Back in the ’70s there were two major players in console manufacture (three if you count Electrodyne, which disappeared early-on due to mismanagement). The Neve name inspired awe among engineers and musicians alike, and had emerged as the primary force in console making to be reckoned with. Much like John Cougar Mellencamp was signed as the American answer to David Bowie, Saul Walker’s Automated Processes Inc. (API) consoles were the American answer to Mr. Rupert Neve’s eponymous consoles. Both desks defined the sound of rock and roll in their own way, with preamps of elegant simplicity that provided the power and punch that rock and roll would continue to thrive on to this day.

Inside the Box

Like all BAE products, the 500-series compatible BAE 312A Mic Pre/DI is made with the highest quality parts, including Jensen input and output transformers and the Avedis 1122 opamp. When discussing API preamps, the important distinction between the 312 and later 512C is the use of coupling capacitors between the output transformer and opamp. The reason for the 312’s success (it’s open punchy sound, particularly on drums) was also its greatest weakness. The 312 had no coupling capacitor between opamp and transformer. As such, if the opamp had any DC offset (a voltage output above the mean amplitude), it might burn out the transformer. The 512C had large coupling capacitor in parallel with a high-frequency capacitor and a resistor for transformer damping. The 512’s opamp also had a servo to eliminate DC offset. The result was increased headroom and the elimination of pops when the phase switch was cut in. Of course, the addition of these components led to a perceived sonic difference between the two. Those who have worked with both often hear the 312 as more open and punchy than the 512C.

To support the fast transient response of the capacitor-less 312A, the BAE 312A uses the Avedis 1122 opamp. The Avedis 1122 is a high-performance, direct-coupled operational amplifier designed specifically for professional audio amplifier applications. The 1122’s were originally made for replacement opamps in the repair of vintage API 312 and 512A mic preamps. It’s based on the same design principles as the 2520, but built with today's high-quality components, to make it operable under a wider voltage range and with lower noise than previously possible. Using no IC's, JFET's, or surface-mount components, the 1122 opamp is picks up where the 2520 left off. Its high output power, low distortion, and wide power bandwidth provides the kind of performance levels appreciated by the working professional.

Outside the Box

The front panel of the BAE 312A mic pre has a matte black finish with orange BAE logo. It has a 1/4" Hi-Z instrument input; buttons for phase reverse, pad, and +48V phantom power; and gain knob. Your basic no-frills design, it’s what’s inside the BAE 312A that counts.

External 24V PSU

The BAE 312A Single-Channel Mic Pre/DI requires the external BAE 24V PSU (not included) to operate. For optimal sound quality, the BAE 24V PSU provides four times the current necessary to power a preamp, and can power up to two BAE rackmount units*. While other rackmount preamps use an internal power supply, BAE chooses to go a different route in the form of an external PSU. The advantages of an external PSU are many. To begin with, not having space constraints allows BAE to design the power supply without compromise. Plus, it makes the shielding concerns of integrated power supplies a non-issue. When power supplies are built into the same chassis as the audio circuitry, nearby audio paths are susceptible to nasty magnetic fields radiated from the transformers, which adds noise and hum. Additionally, the preamp’s components are subject to extra heat generated from transformers, regulators, and rectifiers—and as we all know, heat is the enemy of electronics. It causes unwanted changes in operational parameters and premature component failure.

Since the BAE 24V PSU can power up to two BAE units, the BAE 312A comes with and without power supply in case you already have a BAE unit and power supply. (For BAE 312A without power supply, see BAE 312A Single - PSU and BAE 312A Dual - PSU)

Who’s Using BAE:

"BAE has been an integral part of my record making for many, many years now. I have owned the mic pre's, EQ's, and racks for years. The dedication to costumer service is something one can count on. With the advent of the Avedis 1122 OpAmp, the classic 2520 opamp was brought forward into the future. Mark has also made a point at looking back at certain designs and his attention to detail shows in the new products that he is working on. I am very happy to announce and toast Mark's (Loughman) new ownership in the company. I forecast excellent things to come. — Ross Hogarth, Grammy-winning producer-engineer

"During the recording of many of the Steven Slate Drums sessions, we used lots of BAE mic pres and equalizers. They made it easy to get some of the best drum sounds I've ever heard." — Steven Slate Drums

“What all 312a users say about clarity and punch is absolutely true. They are very versatile pre amps and aside from the obvious with guitars, drums, and vocals, I really enjoy using these pre's with bass and synth sequences.” Ilan Rubin (NIN, Paramore, Lostprophets)

“I love my BAE mic pre-amp. It makes my tracks sound lovelier!” — Jane Wiedlin, The Go-Go's

“I was just screwing around with my BAE 1084 when it hit me, wonder what my Space Bass would sound like in this. I plugged it in and the sound was so pure and natural I thought I was on stage in the ‘Mothership.’ This thing sings with tone, punch, and straight-up good, solid sound that will stand out in a mix with loud drums and guitars.” – Bootsy Collins

“Two thumbs way up! In my opinion, the BAE 1073 and 1084 modules sound every bit as good as the original Neve modules I have used my whole career (we've had blind fold audio "shoot out" tests in my vintage Neve room and there is absolutely no difference). Nothing comes as close to my original Neve EQ/mic preamps as BAE products. And in my opinion, BAE products surpass all the competition in build quality; from the point-to-point wiring, to the audio traces on their cards, original St Ives (Carnhill) transformers, nickel plating, impeccable craftsmanship, and wow! —no old dirty switches and pots. (Did I mention they plugged right in to my vintage Neve 8014 frame from 1970 flawlessly!) Plus, Mark and the staff over at BAE are totally professional and a pleasure to deal with.” — Andy Kravitz, drummer, producer, engineer

Discography: (Imogen Heap, Billy Joel, The Rolling Stones, Simon Townshend, Robbie Krieger, Urge Overkill, Lizzy Grant, The Cheeters, Cypress Hill, James Taylor, Los Lobos, Soloman Burke, Joan Osborne, Taj Mahal, Mark Broussard, Norwood Fisher, Shawn Colvin, Hundred Year Flood, and Sting)

About BAE (British Audio Engineering)

Answering to a higher authority (maintaining the legacy of Mr. Rupert Neve), BAE puts nothing but the very best and their very best into every unit they built. Under the guidance of president/CEO Mark Loughman and Neve guru, Avedis Kifedjian, BAE uses the only highest quality components from the original suppliers, such as Carnhill (formerly St. Ives) and Jensen. All BAE products use discrete electronics and are completely hand-built and wired point-to point (no circuit boards). For more information about BAE, check out RSPE’s Designer’s Perspective feature and get a first-hand look at the inner workings of BAE.

Add the classic API growl and punch to your recordings with BAE’s single-channel 312A Mic Pre/DI. Call or chat with an RSPE representative today.

PRICE: $1,000.00
API 527 500 Series Compressor/Limiter API 527 500 Series Compressor/Limiter

API 527 500 Series Compressor/Limiter

The API 527 is a 500 Series Compresso/Limiter module that takes it's place alongside the family of API VCA based compressors, the 225L and the 2500 Stereo Bus Compressor. Anyone familiar with those units will immediately be at home with the 527. Features common to the line like "feed forward" (NEW) and "feed back" (OLD) gain reduction methods selectable on the front panel, provide a choice of "that old way", or "the new way" of compression, for the highest level of flexibility in signal gain control. The "old way" or Feed-Back method is what most of the classic compressors used for the gain control circuit. The "new way" gain reduction is more typical of the newer VCA type compressors that rely on RMS detectors for the gain control voltage.

There is a "SOFT"/"HARD" switch for an "over-easy" type compression resulting in a very natural, uncompressed sound or a typical sharp knee type that lends itself to a much more severe limiting effect.

The Threshold control sets the initial operating parameter. The 527 can be operated with signal input levels from +10 dBu to -20 dBu.

The 527 features an Output fader control that ranges from minus infinity to +10dB, and output capability is +28 dBu through our 2520 discrete amplifier and a large API output transformer. The output level remains fairly constant regardless of the threshold or ratio control, much like the "more/less" Ceiling control on the API 525 compressor. This allows for live adjustments without any noticeable gain changes in the program level.

The patented THRUST function can be switched in and out via the front panel as well, applying a high pass filter before the RMS detector circuit that preserves that punchy bottom end.

Attack and Release are fully adjustable on the 527. Release time can be adjusted by rotating the inner concentric RELEASE knob. Release time constants: .3 sec to 3 sec. Attack time is adjusted on the outer concentric ATTACK knob, which ranges from 1 millisecond to 25 milliseconds.

The 527 is designed for individual channel use or, through the use of the LINK switch, two units can be combined for Stereo applications via a motherboard bus connection.

The 527 Compressor/Limiter makes use of the 2510 and 2520 Discrete Op-amps and exhibits the reliability, long life, and signature sound which are characteristic of API products.

Don’t forget to check out RSPE’s Rack Revolution, a virtual 500-series rack builder that lets you custom-configure the perfect 500-series lunchbox for your studio, DAW, or mobile recording rig. RSPE carries every 500-series module imaginable, including mic preamps, compressor-limiters, equalizers, and 500 power racks.

LIST: $1,095.00
PRICE: $1,040.25
A-Designs EM-PEQ 500-Series EQ Module A-Designs EM-PEQ 500-Series EQ Module

A-Designs EM-PEQ 500-Series EQ Module


The A-Designs EM-PEQ is a 500-Series module that captures the essence of the classic Pultec EQP-1A sound. One of the most venerated equalizers of all time, the all-tube Pultec EQP-1A has been cherished by recording and mastering engineers for its almost magical ability to improve the sound of nearly any signal running through it. Now, after considerable research and development, the A-Designs Audio EM-PEQ has captured the essence of the highly revered Pultec EQP-1A and placed it in the compact and popular 500-Series form*—with no compromise in sonics or build quality.

Along with modern performance enhancements, the A-Designs Audio EM-PEQ meticulously maintains the EQ-section design and control layout of the original Pultec EQP-1A, as well as its wonderfully smooth musicality. It also has the same frequency settings and inductors that made the Pultec a must-have for capturing the bottom end. Makeup amplification is achieved through the use of the same discrete Class AB amplifier found in A-Designs Audio’s immensely popular solid-state Pacifica mic preamp—putting a slightly unique and modern twist on the classic design of yesteryear.

The EM-PEQ’s controls attenuate high band at 5k, 10k, 20kHz; vary bandwidth AND boost mid to high band at 3k, 4k, 5k, 6k, 10k, 12k, 16kHz; and boost or attenuate the low band at 20Hz, 30Hz, 60Hz, or 100Hz. Boost and attenuation range from 0dB to ±10dB.

Additional features of the EM-PEQ include a nickel-core output transformer, gold Grayhill rotary switches, Wima caps, and a true hard-wired bypass. Plus, instead of using common off-the-shelf chokes, A-Designs uses a custom tapped inductor, wound to the original values as the original Pultec. Along with the classic EQ circuitry, layout, and exceptionally musical sound of the classic Pultec, the EM-PEQ offers fully balanced, noise-free performance and modern impedance specs for easy operation and fast studio integration.

In the world of pro audio recording, there are two types of equalizers: those that you don’t want to hear in action (“surgical or corrective EQ), and those that you do (“color, or character” EQ). The EM-PEQ is one you most definitely do. Unlike any other 500-Series equalizer, the A-Designs EM-PEQ sits on the extreme end of the “character” bench. It focuses on “correcting” that which cannot be fixed by so-called surgical EQs: the enhancement of tone and musicality.

The EM-PEQ is also available as the EM-EQ2, a 2-channel, 2U rackmount version offered at the same price as two EM-PEQs and a 500HR power rack. Whether you prefer to work with the 500-Series form factor or standard rackmount format, both the EM-PEQ and EM-EQ2 are identical in both sound quality and functionality.

LIST: $11,175.00
PRICE: $1,045.00
Summit Audio FeQ-50 Passive Tube / Solid-State Equalizer Summit Audio FeQ-50 Passive Tube / Solid-State Equalizer

With a focus on rich harmonic content and phase coherency Summit Audio offers the FeQ-50 four band parametric, passive equalizer. With six switch selectable frequencies and 14dB of fully sweepable cut or boost on each of the four bands, the FeQ-50 gives you a musically satisfying sonic experience for your tracking, mixing, and mastering projects. I/O includes a total of four simultaneous outputs, -10dB and +4dB vacuum tube out and –10dB and +4dB solid state out. A rich and accessible passive equalizer, the FeQ-50 is simple yet versatile, and is sure to compliment your sound with a dash of flavor unlike any other. Available now for anyone with an ear for quality.

PRICE: $1,099.99
BAE B15 500-Series Multi-Band Equalizer BAE B15 500-Series Multi-Band Equalizer

BAE B15 500-Series Multi-Band Equalizer

A 500 series equalizer from BAE, the masters of recreating vintage sound with modern features and components.

The BAE B15 multi-band equalizer is inspired by the Avedis E15 and designed to create both a clean sound and a colored sound, depending on what part of the circuit is used. The B15 EQ provides a mixture between the punchy, vintage sound of the 312 Mic Pre circuit and the rich, colored sound of the 1073 Mic Pre/EQ circuit in an economically efficient and compact 500 series package. The B15 EQ is an all-discrete design, featuring three bands with (5) selectable frequencies per band. Created to BAE Audio's discriminating vintage specifications, the build and performance of the B15 does not disappoint, complete with Jensen transformers at the input & output stage, Elma gold plated rotary switches and a 15-way gold connector for longer life. The aesthetics of the B15 are equally as sleek, featuring custom-machined aluminum knobs set against a classic matte black housing.

For equipment manufacturers, designing and building high quality 500 series modules is often ripe with challenges, given the significantly reduced physical space. With the B15 and its other 500 series units, BAE Audio has maintained a very high manufacturing standard, as each of its units are hand-wired and assembled in California.


BAE B15 500-Series Equalizer features:

  • Standard 500 series modular size 1.5" x 5.25"
  • 3-bands with 5 selectable frequencies per band
  • +16 dB of boost and cut using continuous variable potentiometer
  • Push button shelving option for low and high frequencies
  • All discrete design
  • High headroom
  • Low noise
  • Jensen Transformer balanced input & output
  • Custom machined aluminium knobs
  • Elma Gold plated rotary switches and 15-way connector for longer life
  • Utilizes Avedis® 1122 Opamps

Don’t forget to check out RSPE’s Rack Revolution, a virtual 500-series rack builder that lets you custom-configure the perfect 500-series lunchbox for your studio, DAW, or mobile recording rig. RSPE carries every 500-series module imaginable, including mic preamps, compressor-limiters, equalizers, and 500 power racks.


Who’s Using BAE:

"BAE has been an integral part of my record making for many, many years now. I have owned the mic pre's, EQ's, and racks for years. The dedication to costumer service is something one can count on. With the advent of the Avedis 1122 OpAmp, the classic 2520 opamp was brought forward into the future. Mark has also made a point at looking back at certain designs and his attention to detail shows in the new products that he is working on. I am very happy to announce and toast Mark's (Loughman) new ownership in the company. I forecast excellent things to come. — Ross Hogarth, Grammy-winning producer-engineer

"During the recording of many of the Steven Slate Drums sessions, we used lots of BAE mic pres and equalizers. They made it easy to get some of the best drum sounds I've ever heard." — Steven Slate Drums

“What all 312a users say about clarity and punch is absolutely true. They are very versatile pre amps and aside from the obvious with guitars, drums, and vocals, I really enjoy using these pre's with bass and synth sequences.” Ilan Rubin (NIN, Paramore, Lostprophets)

“I love my BAE mic pre-amp. It makes my tracks sound lovelier!” — Jane Wiedlin, The Go-Go's

“I was just screwing around with my BAE 1084 when it hit me, wonder what my Space Bass would sound like in this. I plugged it in and the sound was so pure and natural I thought I was on stage in the ‘Mothership.’ This thing sings with tone, punch, and straight-up good, solid sound that will stand out in a mix with loud drums and guitars.” – Bootsy Collins

“Two thumbs way up! In my opinion, the BAE 1073 and 1084 modules sound every bit as good as the original Neve modules I have used my whole career (we've had blind fold audio "shoot out" tests in my vintage Neve room and there is absolutely no difference). Nothing comes as close to my original Neve EQ/mic preamps as BAE products. And in my opinion, BAE products surpass all the competition in build quality; from the point-to-point wiring, to the audio traces on their cards, original St Ives (Carnhill) transformers, nickel plating, impeccable craftsmanship, and wow! —no old dirty switches and pots. (Did I mention they plugged right in to my vintage Neve 8014 frame from 1970 flawlessly!) Plus, Mark and the staff over at BAE are totally professional and a pleasure to deal with.” — Andy Kravitz, drummer, producer, engineer

Discography: (Imogen Heap, Billy Joel, The Rolling Stones, Simon Townshend, Robbie Krieger, Urge Overkill, Lizzy Grant, The Cheeters, Cypress Hill, James Taylor, Los Lobos, Soloman Burke, Joan Osborne, Taj Mahal, Mark Broussard, Norwood Fisher, Shawn Colvin, Hundred Year Flood, and Sting)

About BAE (British Audio Engineering)

Answering to a higher authority (maintaining the legacy of Mr. Rupert Neve), BAE puts nothing but the very best and their very best into every unit they built. Under the guidance of president/CEO Mark Loughman and Neve guru, Avedis Kifedjian, BAE uses the only highest quality components from the original suppliers, such as Carnhill (formerly St. Ives) and Jensen. All BAE products use discrete electronics and are completely hand-built and wired point-to point (no circuit boards). For more information about BAE, check out RSPE’s Designer’s Perspective feature and get a first-hand look at the inner workings of BAE.


Add the clean vintage sound from the Avedis E15 to your 500-series rack with BAE’s B15. Check out RSPE’s Rack Revolution custom 500-series module builder and get started now, or call or chat with an RSPE representative today.

PRICE: $1,100.00
Crane Song Syren 500 Series Tube Preamp Crane Song Syren 500 Series Tube Preamp

Crane Song Syren 500 Series Tube Preamp

A classic sounding 500-series tube preamp with a 12AX7 tube and dual triode circuit.

The Crane Song Syren 500 Series Tube Preamp gives you a classic tube sound with a modern feature set and compact 500 series package. Syren features a dual gain stage circuit and allows overdrive effects, a switch selectable HI-z input, a low cut filter is at 90 Hz and is 24 db/octave, and the pad has -15 db and -25 db settings to allow a wide input range of signals.

The audio path color is changed by modifying the second stage tube circuit so it has negative feedback or does not have negative feedback. This changes the interaction between the tube stages and thus the sound of the pre-amp. With negative feedback SYREN typically has a more accurate audio path with wider frequency response. Without negative feedback it has a more open warmer sound. The OPEN setting is more desired for over drive operation.

Because SYREN was designed for color and not specs the measured values will change greatly depending on the mode of operation. Turing the negative feedback off may or may not result in higher harmonic distortion, but will result in different harmonic content. The changing interaction between the tube stages makes the result difficult to predict. Gain settings, signal level, signal frequency and source impedance all contribute to the tube stage interaction.

The over load LEDs start to light at -6db with respect the tube compression or over load. With a little practice they will become useful in judging the gain settings. The LED’s lighting a small amount does not mean distortion.

The input LED is an indicator of the drive level to the first stage, the only way to change this is with the PAD switch or changing the input signal level. The output gain LED is shows the level of the second tube stage before the OUTPUT GAIN pot. This is affected by the setting of the INPUT GAIN pot.

The output stage features a shielded Lundahl high level line output transformer, all the stepped frequency pots are high quality Grayhill series 56 Rotary Switches and Bourn pots for the gain.

Crane Song Syren unique features:

  • Dual triode circuit with a 12AX7 tube
  • Open/Color switch which lets you apply negative feedback to second stage tube circuit

Crane Song Syren key features:

  • Dual gain stage circuit that allows overdrive effects
  • Hi-z filter (90Hz, 24db/octave)
  • Front-panel DI input; Mic/DI switch
  • 48-volt phantom power
  • Phase-reversal switch

Don’t forget to check out RSPE’s Rack Revolution, a virtual 500-series rack builder that lets you custom-configure the perfect 500-series lunchbox for your studio, DAW, or mobile recording rig. RSPE carries every 500-series module imaginable, including mic preamps, compressor-limiters, equalizers, and 500 power racks.


Who’s using Crane Song:

With a user list including Dave Pensado, Michael Wagener, Tony Maserati, Michael Brauer, Ross Hogarth, Dylan Dresdow, and many more, Crane Song Equipment, such as the Hedd 192, Trakker, Avocet, and STC-8 have achieved secret weapon status in the recording industry. Crane Song is just one of those brands that you know you need to have if you take your audio seriously.

About Crane Song

Crane Song owner, founder, and design engineer Dave Hill has become one of the most respected inventors in the professional audio business. Dave has been doing studio and film sound recording since 1972. Early in the 1980's Dave was asked by a used equipment dealer if he could design a tube compressor that would have the sound of the older tube type devices and still be clean enough to compete with modern devices. The result was the Summit Audio TLA-100. Building on the success of that first design, Dave went on to design multiple tube devices, giving Summit a premier position in pro audio. In 1995 Dave founded Crane Song, a company offering innovative solid-state hardware and software used at the highest levels of pro audio.

If you’ve been looking for a more affordable way to get the classic sound of a tube preamplifier to work for you, put a 500-series Syren Tube Preamp in your 500 lunchbox or rack/PSU. For more information, call or chat with an RSPE representative today.

PRICE: $1,199.00
Miktek CV3 Large Diaphragm Multi-Pattern Tube Condenser Mic Miktek CV3 Large Diaphragm Multi-Pattern Tube Condenser Mic

Miktek CV3 Large Diaphragm Multi-Pattern Tube Condenser Mic

Large diaphragm tube condenser microphone with 9 selectable polar patterns, high pass filter and -10dB pad

The Miktek CV3 is a large-diaphragm tube condenser ­microphone offering nine pick-up patterns. The CV3’s sound is truly large and produces a musical response that will please artists, producers and most seasoned engineers alike. The bottom end is big, warm and tight, with mids that are present and even, along with a high frequency response that’s sweet and airy. The CV3 is ideal for recording single vocalists, and perfect for acoustic instruments, groups of vocals, piano, string ensembles, winds, overheads on a drum kit or as ­ambient room mics.

The CV3 utilizes the MK9 capsule developed by Miktek. This unique capsule features dual 1-inch diaphragms manufactured using 5-micron Mylar with a 0.4-micron layer of evaporated gold, which is precisely tensioned, mounted to carefully-tuned backplates, and set back-to-back to create the final capsule. Tight tolerances and special attention to precise machining of the backplate produce a linear off-axis response that ensures the accuracy of the microphone

The CV3’s head amplifier employs exotic discrete components together with a hand selected subminiature pentode vacuum tube, in which the high-voltage circuit has been uniquely implemented, the CV3 challenges the performance of the best-in-class industry standards without hesitation.

The output stage features a custom AMI transformer, which offers a classic sound and an extended low frequency response found in the earliest versions of the most famous vintage tube microphones.

The Miktek CV3 is hand assembled, tested and packaged in Nashville, Tennessee, USA using components from the US, Europe and Asia. Each microphone includes its serialized ­frequency response graph created during final testing.The CV3 is packaged with its swivel mount in a wooden box, which is set inside an aluminum case with the included power supply unit, 7-pin XLR cable and shock mount.

Miktek CV3 Key Features:

  • Classic Large-diaphragm Tube Condenser Design
  • MK9 Dual 1-inch Capsule with 5-micron Mylar, Evaporated Gold Diaphragms
  • Nine Selectable Pick-up Patterns
  • Custom US Made Miktek Transformer
  • Subminiature pentode vacuum tube
  • High-pass Filter and 10 dB PAD
  • Individual serialized Frequency Response Graph
  • External Power Supply and 7-pin XLR Cable
  • Wood Presentation Case with swivel-mount, shock-mount and rugged aluminum Carrying Case

LIST: $1,999.00
PRICE: $1,199.00
Daking Mic Pre II Daking Mic Pre II

Daking Mic Pre II

Two channel Daking preamp featuring 2X Jensen transformer mic inputs, ¼ in DI, 70dB gain, LED meter, variable HP filter (20 to 200Hz), Discrete Class A circuitry, and outboard power supply. 1U.

The Daking Mic Pre II combines two of Daking’s celebrated stand-alone Mic Pre One units in a single rack space form factor for a surprisingly affordable price. Like the Mic Pre One, the Mic Pre EQ, and the Mic Pre IV, the Daking Mic Pre II circuitry is based on a classic console design of the ’80s with some upgrades: Variable High Pass Filters on each channel, Jensen input transformers, class “A” amplification, extremely high headroom (+24) and a single-sided 48V power supply.

The Mic Pre II’s high pass filter is continuously variable from 10-200Hz, and drops at 12dB per octave. It seems to have a magical ability to clean up the muck while making what remains sound even better. It is extremely helpful to DAW users who inadvertently record subsonics that muddy up tracks and mixes.

Daking Mic Pre II Features:

  • 70dB of gain
  • switchable polarity
  • 20 segment combo VU and “peak hold” LED meter
  • 20dB pad with constant reflected impedance
  • switchable phantom power
  • direct 1/4″ instrument inputs on the front panel
  • balanced XLR and 1/4″ outputs.

Who’s using Daking?

“…. Over the last few years I’ve used Daking mic pres and compressors on recording for artists such as Carole King, Tracy Bonham, Jane Siberry, Hanson, Michelle Branch, Rufus Wainright, Cafe Tacuba, Julieta Venegas, Juanes and many others…” — Joe Chiccarelli

"If you're looking for that vintage sound of a Trident A Range, and you want to add warmth to the digital recording chain, look no further: the Daking mic preamps add a distinctive sonic character that really make your recordings come alive!" — Butch Vig

About Daking Audio:

Geoff Daking started his career as a drummer for the band, The Blues Magoos, who toured with The Who in the ’60s. With two hits under his belt, Daking transitioned to the other side of the glass and engineered records for artists such as Eric Clapton, Hall & Oates, Rod Stewart, Meatloaf, Steve Stills, Cat Stevens, Kenny Loggins, Cyndi Lauper, Joan Osborne, James Brown, Luther Vandross, and many more. Since the ’70s, Daking has built over 20 studios, including facilities for Cyndi Lauper, Joan Osborne, and most recently, a multi-million-dollar facility for Big3 Entertainment.

Back in 1993, audio engineers quickly realized that the new recording equipment didn’t sound nearly as good as the older gear. Geoff Daking decided to do something about it. He approached Phil Wagner at Trident (whose A-Range console designed by Malcolm Toft and Barry Porter is still considered to be the best sounding console for rock & roll) and told Wagner that if Trident produced their preamps and EQs in rackmount form, people would buy them. In turn, Wagner suggested that Daking do it, since Trident had no interest in producing such units. Proving his perceptions correct, Geoff Daking bought the original Trident schematics, borrowed a racked Trident preamp from Lenny Kravitz for reference, and the rest is history.

Using only the finest, best-sounding components, Geoff Daking’s design philosophy is based on the concept of “get home early.” That is to say, Daking products are not loaded down with unnecessary, complex features—just what you need to get the job done right and quickly. Daking Audio makes very musical, solid, high-quality equipment that is very easy to use and cost effective. It’s equally important to recognize that there’s nothing like recording equipment built by someone who not only understands how the electronics work to make the most musical sound, but also has used it to record some of the greatest artists the world has known—and that defines Daking Audio.

LIST: $1,349.00
PRICE: $1,199.00
API 525 500 Series Discrete Compressor API 525 500 Series Discrete Compressor

API 525 500 Series Discrete Compressor

Authentic reissue of API's original 525 compressor from the early ’70s

The 500-series API 525 Discrete Compressor is a dead-on re-issue of the original modular 525 compressor/limiter. Remaining one of the most popular compressors of all time, the API 525 has a number of unique design innovations including its Ceiling control, which allows you to change compression ratio on the fly while maintaining a constant output—no gain-makeup required. Tweaking the Ceiling control brings out the body of guitars and the resonance of synthesizers. A workhorse compressor that can be linked for stereo bus operation, the API 525 particularly excels on vocals. If you’ve heard Steve Perry’s vocals with Journey, you’ve “heard” the API 525 compressor in action. The 500-series API 525 Discrete Compressor is also great for presence and thickening sounds.

API 525 unique features:

  • Exact reissue of API's original 525 compressor
  • Ceiling control combines key functions
  • Traditional API fully discrete circuit design

API 525 key features:

  • Peak-detecting feedback compressor/limiter
  • Variable threshold and output levels
  • Analog VU meter for monitoring gain reduction
  • 4 switchable release modes
  • De-ess function
  • Active balanced input/output
  • Hardwire bypass

API 525 — Inside The Box

Originally released in the 70's, the API 525 re-issue was built using the original blueprints and spec-control drawings from the API archives. A re-issue doesn’t get any closer than this. The API 525 is ideal for reduction of distortion due to overload or over modulation of program peaks. Attack time is as fast as 15u/s. Four auto-release modes are offered: 0.1s, 0.5s, 1.5s, and 2.0s. A de-ess function inserts an inverse vocal energy curve filter in the detector for effective sibilance/pop reduction.

The API 525’s unique Ceiling fine-tuning control offers extreme ease of operation by providing up to 20dB of compression or limiting in 2dB steps while maintaining a constant peak output level. The Ceiling control can increase gain reduction (lower threshold) while simultaneously raising output level to match, so you can adjust dynamics on the fly without level changes.

Full range of operation is achieved with signal input levels from -15dBm to +20dBm, and output capability is +24dBm through an integral output transformer. Release times vary with frequency, with high frequency/full bandwidth content released faster than lower frequencies for natural envelope tracking. Attack time is fixed, carefully chosen by API to catch the fastest peaks without pumping. Although the API 525 compressor is designed for single-channel use, two or more 525s can be linked for multi-channel compression.

The API 525 compressor employs a feedback design, which means that the input signal passes through the gain control element to the detector (or control voltage converter), which sends the control voltage back to the gain control element and on to the output. This is a self-correcting system, wherein Attack, Release, and Ratio cannot be strictly defined as they are with feed-forward designs, and will change with the operation of the feedback loop. While not as fast and accurate as a feed-forward system, the feedback design is more musical and pleasing to the ear. After all, math is our attempt to describe nature, but as renowned audio researcher Dr. Richard Heyser once said, “Nature does not solve equations.”

API 2520 Op-amp

API’s 2520 Op Amp found in the 525 is responsible for the API sound. Designed by API engineers, the 2520 op-amp is a high-gain, wide-band, direct-coupled amplifier built specifically for audio applications. The circuit mainly derives its characteristics from the performance of its passive elements connected into the feedback loop, which provides predictable, stable performance. The 10-discrete transistor amplifier is encapsulated in a thermally conductive epoxy, which protects against thermal shock, vibration, and humidity, assuring long life and reliable performance.

API 525 — Outside The Box

Looking over the front-panel real estate of the API 525, you’ll see two small rotary controls at the top that set the initial operating parameters: Input (threshold) and Output (make-up gain). Below these controls are a Gain-Reduction Meter; Release, which are two switches that select four release times: all out = 0.1s, 1 in = 0.5s, 2 in = 1s, and all out = 2.5s; Compression switch, which sets ratio at 2:1; Limit switch for 20:1 ratio; Off switch, which shuts off the gain reduction but keeps the unit inline (to add the character of the 2520 op amp and transformers); hardwire Bypass switch; De-ess switch, which removes sibilance; and the Ceiling knob, which works the same as turning the threshold and output controls up or down at the same time. The API 525 Discrete Compressor has a balanced input and a pin-out that is the same as all the other 500 series modules.

API Audio's VPR Alliance

The VPR Alliance is a program of standardization and consistency guidelines for approved manufacturers wishing to design products for API's 500-series rack format. The program provides complete design specifications for manufacturers interested in producing third-party modules that physically fit and electronically conform to API's rack specifications.

The creation of the VPR Alliance was encouraged by the overwhelming popularity of API's 500-series racks, including the 10-space 500V and the six-space lunchbox®, which led to a proliferation of third party modules that fit the API format. Typically installed into API racks, these third party modules had raised issues of warranty and interaction with API-manufactured modules in the same rack.

Because of the variables related to those third party modules, API had previously been forced to declare that inserting any third-party modules into a 500V or lunchbox voided the warranty on that rack. Through the VPR Alliance, API is now able to eliminate confusion as to which third-party products definitively do and do not void the API warranty. The VPR Alliance is a straightforward resolution that saves the company time and money while promoting goodwill to API customers.

API’s customers benefit from the VPR Alliance with the knowledge of exactly which products are approved for placement in API racks; customers have a wider range of module choices for their racks that have been tested by API staff for specification compliance.

An Abbreviated History of API

It all began with a dream. It was 1968. The company: Automated Processes Inc., formed by men with a vision. Best known for their now legendary "2520 amplifier", this unique amp has been and will continue to be the heart of all API discrete products. It continues to provide reliability and sonic purity unmatched by the competition. The resulting console met the needs of the music, commercial and broadcast industry.

API became the leading audio broadcast console manufacturer for radio and television networks and high profile stations. In addition, recording studios, large and small, began using API...and receiving rave reviews from engineers and producers. There are over 700 API consoles across the nation and around the world, including the three major networks. Over thirty years later, many of these consoles are still in daily use in some of the most prestigious recording and broadcast facilities in the world because, to date, there are few, if any consoles of equal sound quality at a cost-effective price.

Equally useful as a tracking, mixdown, or program compressor/limiter, the API 525 gives you vintage dynamics control and an easy-to-use, multi-function control set. For more information, call or chat with an RSPE representative today.


LIST: $1,295.00
PRICE: $1,230.25