A-Designs P-1 and EM series modules


The introduction of "modular units" is not a new concept but recently there has been a gradual standardizing of unit sizes with different manufacturers working to the same specifications.  As a result, units are now interchangeable from one manufacturer's PSU to another.  The A-Designs range of 6 modules - all original designs - are fully compatible with the API 500 series "Lunchbox" modular rack frame and power supply, also those from Brent Averill and OSA.

As this format is becoming so popular, API has formed a confederation of manufacturers called the VPR Alliance, who's products are approved by API for fitting into the Lunchbox.  A-Designs is of course among them.  Click the logo for more info.

A-Designs P-1 and EM Series modules

 "Going from the PRO37 to the P-1 to the BAC-500 and direct to Pro Tools is a super-clean signal path for super-deliciousness," he says. "A lot of mix engineers like to have a compressed channel of the drums that they can sneak into the mix to give it a fuller, fatter live sound, and the combination of the P-1 and BAC-500 is really incredible for that. That pairing is a classic--like Lennon and McCartney, or Lewis and Martin--they're just perfect together."
Carl Bisquera, LA session drummer, March 2009

A-Designs P-1 mic pre module (API 500 series lunchbox compatable)The P-1 is inspired by the highly successful Pacifica microphone pre-amplifier, and captures the unique sound of the 1970's Quad Eight Ventura, Coronado and Pacifica Consoles.  It includes the following features: Pad, phase reverse, 48v phantom power, ¼" direct inject "High Z" for instruments, cream coloured face plate, red LED indicator for phantom power, aluminum cast red knob, custom wound input and output transformers, and thumb screws for easy install.

A-Designs EM-Silver mic pre (API 500 Series "Lunchbox" compatibleThe EM (Erickson/Montessi) Series, consisting of EM-Red, EM-Blue, EM-Silver and EM-Gold modular Microphone Pre-amplifiers are variations on the P-1.  Each unit has its own distinct tonal character.

The EM-Silver has the same features as the P-1 except for the custom wound steel output transformer.  This unit will take you back to earlier times, when ribbon microphones were the standard and all transformers were made of steel. There is a real magic happening here!  The steel transformers translate into a darker, warmer sound - a classic combination with ribbon microphones - and great for bass guitar and keyboards, also kick drum with high-end condenser microphones.

A-Designs EM-Blue mic pre module (API 500 Lunchbox  series compatible)The EM-Blue with its high nickel wound output transformer will produce a much brighter tone, with an airy top end.  This module is perfect to use with darker sounding microphones or on instruments like snare drums, guitars, etc. that benefit from a crisp recorded sound.  With an alto vocalist this module can sound almost 'heavenly'.  And if you use the DI feature you just might want to hear what an electric guitar sounds like going through nickel transformers - pad the input and crank the gain for some 'growl'.

A-Designs EM-Red mic preThe EM-Red has a custom wound INPUT transformer and the same output transformer as the P-1, which produces a somewhat different sonic character by bringing the "mid levels" forward in a recording. This unit is perfect for recording any instrument which requires accents on mid range tones.  Absolutely amazing on toms (both rack and floor) and the 'up front mid' is great for acoustic guitars, too.


A-Designs EM-GoldThe EM-Gold is the latest pre-amplifier in the EM Series.

A-Designs took the custom wound output transformer of the EM-Silver and combined it with the custom wound input transformer of the EM-Red.

The results here made for the perfect sound on a floor tom!

It also produced great results with a number of microphones for vocals, Bass, and MP3/Drum Machines.  To try to describe the sound, we can say that the EM-Gold produces the dark end of the EM-Silver with more “up front” mids.



The valve Pultec EQP-1A goes down in most people's book as one of the most venerated equalisers of all time, loved by both recording and mastering engineers for its almost mythical ability to improve the sound of, well, just about anything running through it.

A-Designs Audio has shrunk this highly sought after filter design into the now red-hot (not literally!) 500 Series format without compromise to either build quality or sonics. The EQ section design and control layout of the classic EQP-1A has been meticulously maintained, as well as its wonderfully smooth musicality.

Makeup amplification is achieved through the use of the same discrete Class AB amplifier found in A-Designs popular solid-state Pacifica mic pre, putting an extra twist on this classic design.

Additional features include a nickel core output transformer, gold Grayhill rotary switches, Wima capacitors, and a true hard bypass. Instead of using off-the-shelf chokes, A-Designs uses a tapped inductor, custom-wound to the original values. Fully balanced, noise-free operation with modern impedance specs make for simple operation and fast studio integration.

The new EM-PEQ is an approved API™ 'VPR Alliance' product, so may also be used in Brent Averill racks and A-Designs Audio’s 500HR.

With the launches last year of the P-1 and EM-Series preamplifiers (EM-Red/Blue/Silver, and recently the EM-Gold), A-Designs Audio is fast becoming a significant player in all things '500 Series'. The blend of classic sound and modern function offered by the new EM-PEQ is further proof of a company dedicated to creative design, quality and value.

The EM-PEQ does require 48v to operate so please check your racks for this feature.



Pete's Place Audio


Pete's Place Audio offers another Lunchbox-format product, a 500 Series compressor module known as the BAC-500.

Designed by Brad Avenson of Austin, Texas-based Avenson Audio, the BAC-500 is a feedback-style FET compressor built around two discrete op amps and a custom wound output transformer.

"We are thrilled to finally be collaborating with Brad on this project," says Pete's Place Audio President Lisa Montessi. "His experience, knowledge and passion really shine through in everything he creates and the BAC-500 certainly is no exception. It's a fantastic compressor and it's going to make a lot of 500 Series fans very happy."

From the top down, the BAC-500's faceplate features a large silver rotary input knob, smaller pots for attack, release and ratio, and a large output knob at the bottom. Additional features include a three-position sidechain contour switch, eight-LED gain reduction meter, and pushbuttons for distortion and bypass.

The module's attack control runs from fast to quite fast, while the release control exhibits a fairly wide range, enabling the compressor to go from "pumping, breathing fast" up to approximately a second and a half. This allows sounds to "hang" a bit when using the device purely as a leveler or limiter.

The ratio control features five positions ranging from 2:1 to 20:1, with a sixth position marked as "8!". According to Avenson, "The infinity control has a little exclamation point next to it because, not only is it really flat, but it also puts you in that spot where you can do some over-compression and other interesting things. It changes where the threshold starts to compress as well, so it gives you different varieties of tonal characteristics to play with."

The BAC-500's sidechain toggle switch offers a choice of three possible settings: flat, high-pass filter, and an option that somewhat exaggerates the high end while simultaneously cutting the low end. "The overall effect of this third setting is somewhat like a de-esser fed into the sidechain, but it's a little wider than that and quite good for taming a variety of things that are overly bright," Avenson notes.

With all of the controls essentially cranked between the input and output knobs, the BAC-500 is capable of delivering nearly 50 dB of gain, which can be very helpful in compensating for serious gain reduction issues caused by greatly compressing dynamic range.

The bypass button found below the output knob is a true relay bypass, while the adjacent distortion button allows the user to overload the FET for color. "A lot of FET compressors use tricks to linearize the FET as a compression element and make it sound cleaner because if they're used by themselves, they're really pretty raunchy sounding," says the designer. "So this switch allows you to play with how much of the distortion characteristics of the FET you get. By engaging it, you're getting a lot more second harmonic distortion. It's basically a way to kick in a more aggressive sounding compressor without changing any of the other settings. You can dial in the amount of dirt you want."

Avenson sums the BAC-500 up by adding, "Although this product is largely designed to provide a bit of color and flavor--and not be too heavy handed--it really does possess that nice 'bite' that is characteristic of FET compressors and perfect for cranking down on things like drum room mics when you need it."

A-Designs Audio 500HR 2-Slot Rack Frame with Power Supply

The 500HR is a dual slot, single space, rack mounted frame with power supply for A Designs and other 500 Series compatible audio modules.  With a cream-colored faceplate, the 500HR is housed in an all-metal chassis for maximum durability, and offers a complete mounting and power supply solution for the A-Designs "Lunchbox" products, each of which conforms to the API™ 500 Series format.  These include the P-1, the EM Series of EM-Red, EM-Blue, EM-Gold and EM-Silver modules, and the new EM-PEQ equalizer.  Both a rocker-style on/off switch and 48V phantom power LED can be found on the right side of the front panel, while the rear panel features two sets of XLR ins and outs in addition to a standard IEC power connector

A-Designs 500HR powered rack module

You can use the 500HR and A Designs module combinations in four basic ways:

1. Loaded with two preamps it becomes a dual channel Mic Pre

2. Loaded with two EQ’s it is a dual channel EQ

3. Loaded with one preamp and one EQ and LINK engaged, it is a complete pre/post EQ recording channel

4. Use one preamp and the EQ in the R52 and bypass your pre on your guitar/bass/keyboard amplifier and have     a totally different amp for any live situation.

The 500HR works normally in dual mono, via an XLR in and out for each channel.  This enables use as a conventional two channel system for 500 mic pre's or EQs.  There arer a number of other interesting applications:- for example, when combined with an A/D converter, the device can make an excellent choice for mobile recordings for broadcast.  Also, with so many people doing voiceovers for TV and film, plus vocal production work for audio books and radio, the 500HR combined with the right modules and a laptop is again a perfect solution for those markets.  And, of course, many discerning live sound engineers will be pleased to see that they can now put a pair of studio-grade processing modules into a 1U rack.

Note: we have found that some units in circulation will draw more mAs than that advised by The VPR Alliance, and some are double wide. If in doubt, please check with us before purchase.

A-Designs 500HR powered rack frame rear panel


500HRConnections: Two XLR Inputs and two XLR Outputs,
electronically balanced (unless using another make
of module which has unbalanced outputs).
Power Requirements: 230 VAC - 14W.
DC Power Output per channel: 140mA @ 16VDC.
Dimensions: 19" x 1.75" x 10.25" [1RU].
Weight (empty): 3.2 kg/7 lbs.


Curt Bisquera Drums Up Some "Super-deliciousness" With A-Designs

Top L.A. session drummer adds multiple P-1, 500HR, and Pete's Place BAC-500 modules to his recording signal chain

LOS ANGELES - March 2009 -- Having performed on recordings and/or tours for Elton John, Mick Jagger, Celine Dion, Tom Petty, Johnny Cash, Ricky Martin, Tina Turner, Bonnie Raitt and many, many others, it's almost conceivable to think that the list of top artists that first-call session drummer Curt Bisquera hasn't worked with is shorter that the one he has. So, needless to say, it came as quite a compliment to A-Designs Audio when he recently chose to improve his kit's sound in the studio with the addition two P-1 preamplifier modules and two new BAC-500 compressors (from sibling company Pete's Place Audio), all housed in a pair of 500HR power racks.

"Kirkee B.", as he's sometimes known, is now regularly using half of his 500 Series modules to preamplify and compress an Audio-Technica PRO37 room mic that ultimately feeds into a Pro Tools system at his own Black Couch Studios in Westlake Village. "Going from the PRO37 to the P-1 to the BAC-500 and direct to Pro Tools is a super-clean signal path for super-deliciousness," he says. "A lot of mix engineers like to have a compressed channel of the drums that they can sneak into the mix to give it a fuller, fatter live sound, and the combination of the P-1 and BAC-500 is really incredible for that. That pairing is a classic--like Lennon and McCartney, or Lewis and Martin--they're just perfect together."

Bisquera had initially been exposed to A-Designs through Tony Shepperd, an engineer/producer friend who had recorded his own band, the Bisquera Brothers, several years ago. "Tony introduced me to the Pacifica, which really turned me on," he says. "Seeing that the P-1 basically put the Pacifica's mojo into a 500 Series format, I knew that's what I wanted to use as my mic pre.

"When I spoke with Peter Montessi at A-Designs about purchasing a P-1, I mentioned that I was also in the market for a compressor. He suggested that I try out the new Brad Avenson-designed BAC-500 from Pete's Place and tell him what I thought of it. So I took one with me, set it up with the P-1 back at my place and was floored. It surpassed every other compressor I had tried out, and I thought 'okay, that's it, I'm done. If I have a P-1 and a BAC-500, I'm good to go.'"

Although Bisquera had initially purchased only a single P-1, BAC-500 and 500HR, he was so impressed with the results that he immediately added a second set in order to use the equipment for drum overheads, keyboards and other stereo applications.

"I've been finding myself using these modules for much more than just drums," he adds. "I used them on a guitar track the other day and it was just screamin'. The pair is awesome on vocals, too. My wife, Daniela, is a professional jazz vocalist and she sounds phenomenal though the combination. Also, Art Kimbro, a dear friend of mine, came in recently to do some voiceover work and he was amazed how good they made him sound. I'd be really surprised if he doesn't buy a set for himself."

Aside from the sonics, another thing that Bisquera appreciates about the 500 Series gear is its portability. "I'm using this stuff all the time in my own studio, but what's great about the 500HR is that I can very easily pop it out of my rack and bring it with me to sessions in other studios. For example, I just went up to Dave Way's place, The Pass, the other day and took my modules with me, which was awesome. After all, these things are a part of 'my sound' now."

For more information on Curt Bisquera, visit www.curtbisquera.com.


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