recursal/Fanatic-Fandom huggingface dataset:
LaChapell Audio 583s MK2

**LaChapell Audio 583s MK2** is a pre-amp for the 500 series, manufactured by LaChapell Audio.

## History

The LaChapell Audio 583s MK2 was released in 2014. It replaced the LaChapell Audio 583s (MK1).

## Official description

>
> The LaChapell Audio Model 583s is the world’s first vacuum tube preamplifier designed for the 500 series format. Now the 583S mk2 is a single bay unit! The LaChapell Audio 583S mk2 is the latest example of our legendary 583 vacuum tube preamplifier for the 500 series format. Based largely on our 992EG, the 583s mk2 is the perfect solution for those looking to add that extra warmth and character to their “lunch box” with versatility that only a properly powered 12AX7 vacuum tube can provide.
>
>
> POWER SUPPLY The 583S mk2, was built to meet API/VPR certification requirements. Using multiple internal DC/DC converters, the 583’s 12AX7 tube enjoys proper power for both plate (250 volts) and filament (12 volts). Unlike some other tube preamps for the 500 series, we do not starve the tube of voltages in any way. And, since this all occurs within the 583 module, there is no worry of harming your 500 series power supply.
>
>
> COMPONENTS The 583s mk2 features the CineMag CMMI-10 microphone input transformer and Jensen’s best line output transformer; the JT-11. Typical preamplifier features are available as well including 48v, a 20 dB pad and polarity reverse. The mk2 also sports an auto-switching, transformer-less Hi-Z input for instruments.
>
>
> CONTROLS In operation, the user has individual control over the input and output gain stages via 41-position potentiometers. This, like its 992 older brother, provides total flexibility to explore the 583s’ broad sonic pallet; enhancing its versatility for all of your recordings. The new mk2 also includes a convenient handle for easy insertion and removal.
>
>
>
>

## References

1. ↑ https://www.gearslutz.com/board/product-alerts-older-than-2-months/941914-lachapell-583s-mkii.html
Chameleon Labs CPS-501

**Chameleon Labs CPS-501** is a 1-slot rack for the 500 series, manufactured by Chameleon Labs.

## History

The Chameleon Labs CPS-501 was scheduled for release in 2010 releases, although it is unclear if it was actually released that year.

## Official description

>
> **Rack Mount Your 500 Series Modules**
>
>
> Looking to mount your 500 series module in a 1U rack space? The Chameleon Labs CPS-501 Powered Chassis will power your API 500 series compatible modules while storing them in a convenient 1U half-rack unit. Chameleon labs designed the CPS-501 with some forethought at keeping you signals cleaner by keeping the transformer away from sensitive electronics by using an inline AC adapter. The back panel of the CSP-501 features an XLR in and XLR out, as well as a TRS insert. The heavy-duty steel chassis will keep your 500 series gear protected from the rigors of the road and gigs. The CPS-501 chassis is expandable to incorporate two units, or to even use on your desk. Protect and power your 500 series modules with the Chameleon Labs CPS-501 Powered Chassis.
>
>
> **Chameleon Labs CPS-501 Powered Chassis at a Glance:**
>
>
>
> * Convenient power solution
> * Rugged Construction
> * Flexible and expandable design
> * Convenient power solution
>
>
> Since all 500 series modules need power, the Chameleon Labs CPS-501 Powered Chassis is a great solution. The inline AC adapter keeps the power transformer away from your sensitive electronic equipment to help reduce hum and extraneous signals. The included AC extension cable can power up to eight CPS-501 units as you add them to your rack.
>
>
> **Flexible and expandable design**
>
>
> The Chameleon Labs CPS-501 Powered Chassis is built to work with all 500 series modules. It even complies to the Neve Portico dimensions for placement into Neve console frames. You can quickly rackmount one or two CPS-501 units with the RM1 and RM2 rackmount kits. If you have a 500 series module that does not need 48V power, the CPS-501 is built so that you can easily lift Pin #15 and disable the 48V power without modifying the power supply.
>
>
> Chameleon Labs CPS-501 Powered Chassis Features:
>
>
>
> * Powers API 500 series compatible modules
> * 1U half-rack design
> * XLR in and out
> * TRS insert
> * 6mm steel chassis construction
> * Inline AC adapter puts transformer away from module
> * AC extension cable powers up to eight CSP-501 units
> * Pin #15 can be lifted to remove 48V
>
>
>

## References

1. ↑ https://www.gearslutz.com/board/so-much-gear-so-little-time/429027-chameleon-labs-goes-500-7681-microphone-preamplifier-cps-501-powered-chassis.html
Earthworks 521 ZDT

**Earthworks 521 ZDT** is a pre-amp for the 500 series.

## Official description

>
> * Clean, uncolored 500 series preamp
> * Solid-state, transformerless
> * Switchable 48V phantom power
> * Polarity invert switch
> * Peak amplitude clip detection
> * Transparent gain switchable from 5dB to 60dB in 5dB steps
> * Ultra-low noise floor
> * Ultra-wide bandwidth
> * Suitable for most ribbon, dynamic or condenser microphones
> * Requires a 500 series rack
>
>
> Based on the Earthworks ZDT Zero Distortion Preamplifiers™ technology designed by David Blackmer, the 521 brings the exacting standards of the Earthworks Zero Distortion Technology preamplifiers to the convenient 500 series format.
>
>
> The solid state 521 features switchable phantom power, polarity invert, and peak amplitude clip detection, just as in the original 1021 single channel ZDT Preamp. The transformerless output stage of 521 ZDT easily drive long cable runs without loss of quality, making it ideal for long cable runs. Transparent gain is switchable from 5dB to 60dB in 5dB steps.
>
>
> The Earthworks microphone preamplifier topology provides outstanding common mode rejection, excellent overload margin and an incredibly low noise floor, combined with the ultra wide bandwidth of the ZDT Preamps and distortion of less than 1 part per million. This exceptional level of performance is maintained over an extensive range of impedances applied to the input making the 521 suitable for practically any microphone – ribbon, dynamic or condenser.
>
>
> **Specs:**
>
>
>
> * Preamp Type: Solid State
> * Number of Channels: 1
> * Frequency Response: 2Hz to 100kHz ±0.1dB, 1Hz to 200kHz ±0.5dB
> * Impulse Response: 1.4µs
> * Distortion: XLR out: less than 1ppm (0.0001%); 1/4” out: 0.001%
> * Input Noise: 1.6nVHz½ at 20dB gain; 0.6nV/Hz½ at 60dB gain
> * EIN: -132dBV at 20dB gain; -143dBV at 60dB gain
> * Slew Rate: 22V/µs
> * Output DC Offset: ±1 mV typical, servo balanced
> * Input / Output Connector: 500 Series EDAC Edge connector
> * XLR Input Impedance: 10KΩ phantom on, 100KΩ phantom off
> * Front Panel Balanced Out: ¼” TRS XLR Fem. balanced transformerless (variable)
> * Dimensions: 1 500 series rack space 1.5” x 5.25” x 6”
> * Weight: 0.8 lb. (0.36kg)
>
>
>
Radial PowerPre

**Radial Engineering PowerPre** is a pre-amp for the 500 series, manufactured by Radial Engineering.

## History

The Radial PowerPre was released in 2010.

## Official description

>
> * Hand selected 100% discrete electronics
> * Hammond broadcast transformer output
> * AccuState™ low-noise input circuit
> * 3-position Vox control for added air or punch
>
>
> The Radial PowerPre™ is a high performance microphone preamplifier designed to be used with the Radial Workhorse and other 500 series modular racks. It features 100% discrete components for optimal signal transfer and employs a 'vintage' Hammond broadcast output transformer for warmth and exceptionally smooth tone.
>
>
> The design begins with a front mounted XLR for instant connectivity plus a recessed 48V phantom power switch for safety. Unlike most mic preamps that require careful gain adjustment to avoid troublesome noise, the PowerPre is equipped with the newly developed AccuState™ input stage that automatically optimizes signal-to-noise at all levels with up to 55dB of gain. This is supported with a full 10 segment LED meter for precise signal monitoring.
>
>
> To add extra character; a 3-position Vox control lets you set the PowerPre to 'breath' for added high frequency air such as when accentuating a vocal track or adding harmonic content to an acoustic guitar. The 'punch' setting adds body when recording electric guitar or can be used to fatten a voice. When set to linear, the PowerPre delivers a truly natural rendering for orchestral recording that will suit the most demanding purist. This is augmented with a gentle high-pass filter that helps control low end resonance when layering acoustic instruments.
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> Ultra quiet, low noise and exceptionally warm sounding… the PowerPre makes spectacular audio easy.
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>

## References

1. ↑ https://www.gearslutz.com/board/product-alerts-older-than-2-months/454713-radial-powerpre-mic-preamplifier.html
Bereich03 Audio Density (mono)

**Bereich03 Audio Density** is an harmonic saturation processor for the 500 series, manufactured by Bereich03 Audio. It was also released in a stereo version.

## History

The Bereich03 Audio Density was released in 2012. It was the first module manufactured by Bereich03 Audio.

## Official description

>
> I developed the density as I didn't have a device in my studio that could produce analog saturation during tracking and mixing. I build it in the 500 format to allow for easy integration into existing systems and to make it easily expandable.
>
>
>
> * Frequency Response: 10Hz - 20kHz (-1dB)
> * Input Impedance: 20kOhm, balanced
> * Output Impedance: 44Ohm, balanced
> * Power Consumption: 94mA @ +16VDC, 94mA @ -16VDC
> * Power Requirement: +/- 16V
> * Weight: 275g (0,6lbs)
> * Dimensions: 1 slot
>
>
>

## External links

* Official product page
* Review in *Sound on Sound*

## References

1. ↑ https://www.gearslutz.com/board/product-alerts-older-than-2-months/658810-500-prototype-density-2.html
2. ↑ https://www.gearslutz.com/board/product-alerts-older-than-2-months/658810-500-prototype-density.html
CAPI VP312

**CAPI VP312** is a pre-amp for the 500 series, manufactured by CAPI.

## Official description

>
> **Classic Audio VP312**
>
>
> The VP312 is a clone of the vintage API 312 mic preamp. It is about as close to the original 312 as you can get right now, and at this price it is seriously unbeatable. You won't find any compromises in quality either. As with all of the equipment from CAPI the VP312 has custom Ed Anderson transformers and top quality components throughout.
>
>
> The VP312 only has two minor differences from the original 312 circuit (which can be left off if desired). Here's Jeff's explanation...
>
>
> From CAPI-gear.com:
>
>
> There are only two main differences in the audio path between a vintage 312 card and the VP312. The first difference is the allocation on the board for a loading resistor, R2. This is often referred to as the Load R and is used in many of the mic preamp circuits including the VP25 and VP26 preamps. The input transformer you use will really dictate whether or not you use this Load R as it is optional and not required. With the EA2622, the circuit sounds great both with and without it. This Load R was typically not found on a stock API 312 card. The second difference is R12 which immediately follows the discrete opamp’s output. I use a zero ohm or jumper resistor for R12. I have utilized this R12 for two reasons. The first is as a little protection for the remaining circuit if there is some sort of rare DOA failure. Hopefully R12 will smoke before any other damage occurs. The second reason is merrily to “jump” over a few PCB traces. I really don’t think it degrades the sound using a zero ohm resistor. A hard wire jumper could also be used.
>
>
> **Features**
>
>
>
> * 60dB of gain provided by a 2520 style opamp, I regularily stock the GAR2520, GAR1731, and the SL2520 Red Dot.
> * -20dB Pad switch, polarity switch, and mute switch.
> * Fast drain 48V Phantom power.
> * Output attenuator which allows you to drive the opamp and 2503 output transformer HARD and attenuate back down to digital safe levels (this is something rarely implemented on API style preamps, and makes for a huge variety of tones).
>
>
>
Electrodyne 501

**Electrodyne 501** is a pre-amp for the 500 series.

## History

The Electrodyne 501 was released in 2009.

## Official description

>
> **Electrodyne 501 discrete two stage studio preamp:**
>
>
> The Electrodyne 501 is a two stage discrete transistor, transformer coupled preamp with active DI, using classic 1969 / 1970 design technology. Each amp stage is individually optimized for peak performance using Electrodyne factory engineering notes and selected high performance components identical to the originals. The transformers are made by Electrodyne’s original manufacturer to exacting factory specifications. The active DI circuit presents an almost immeasurable load to sensitive musical instrument outputs allowing incredibly accurate capture of the instruments true tone. The output of the DI circuit is designed to directly connect and interact with the mic input transformer to allow maximum tone options.
>
>
>
> * Maximum Gain: 68db. Adjustable over 50db in 2db steps with two ranges using 20db pad.
> * Output level control: Infinitely adjustable from 0 (off) to +6db over unity.
> * Input impedance: Microphone, 50 / 200 ohms selectable. DI, over 7 megohms.
> * Output impedance: 150 ohms
> * Distortion: 0.02%typical over entire gain range.
> * Maximum output: +30db at less than 0.8%thd. (+29.5db at 0.06%thd)
> * Frequency response: +/- 0.25db, 10hz to 60khz.
> * Signal to noise: -80db typ, -60db at absolute maximum gain.
> * Clip indicator: Monitors all three amp stages and illuminates when any stage is 3db from clip.
>
>
>

## References

1. ↑ https://www.gearslutz.com/board/product-alerts-older-than-2-months/450802-electrodyne-500-series-press-release.html
Chandler Limited TG2-500

**Chandler Limited TG2-500** is a pre-amp for the 500 series.

## Official description

>
> The Chandler Limited TG2-500 pre-amp is a recreation of the rare EMI TG12428 pre amp used in EMI/Abbey Road Studios recording and mastering consoles from the late 60s and early 70s. The sound of the EMI/Abbey Road Studios equipment is world renowned, and imparts a unique and pleasing sonic character as heard on many famous recordings done at Abbey Road including The Beatles’ “Abbey Road” and Pink Floyd’s “Dark Side of the Moon” albums. For the first time ever, the legendary TG2 pre-amp sound is available in 500 Series format.
>
>
> The TG2-500 microphone pre-amplifier features the same discrete, transformer-balanced amplifiers as Chandler Limited’s TG series: TG2 Pre Amp/DI, TG Channel MKII, and TG1 Limiter.
>
>
> We’ve taken the microphone pre-amplifier and line amplifier from our highly acclaimed TG2 Pre Amp/DI and packaged it for the industry standard 500 Series format, while retaining the sound of Chandler Limited’s TG2 Pre Amp/DI. The aural quality has often been characterized as a creamy, smooth tone with a surprisingly open, clear top-end. The sound, as explained by many users, has "warmth" and punch, but with a "beautiful" expanded top end. In fact, the TG2-500 microphone preamplifier does have a small rise in its top-end frequency response and some warmth inducing distortion, which contributes to its sound.
>
>
> Bring the sound of the Chandler Limited TG2-500 pre amp and EMI/Abbey Road Studios home to your 500 Series rack today.
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>
>
DACS Clarity MicAmp 500

**DACS Clarity MicAmp 500** is a pre-amp for the 500 series.

## Official description

>
> If a microphone pre-amp adds anything other than clean gain to the audio signal being sent to the recording medium, whatever that extra might be will then become an integral part of the recorded signal. And as actually embedded in the signal, any undesirable addition will be extremely difficult to remove at a later stage. Likewise, if anything is subtracted from the audio signal along the same path, it will be irretrievably lost. If the preamp loses it, it is lost to everything downstream. This is why the microphone pre-amp is critical for the quality of the recorded sound – because no amount of post-production knob-twiddling can ever re-create the detail obliterated, or restore the dynamics flattened by, an inadequate mic pre.
>
>
> So the ideal microphone amplifier should be designed to eliminate both of these types of signal degradation. It should be:
>
>
>
> * as low noise as possible, at whatever level of gain
> * grain-free and allow the transmission of a literally high-fidelity signal, which is faithful to both the frequency and dynamic ranges of the source.
>
>
> This ideal is very hard to achieve – but DACS talked to recording engineers; they said it’s what they wanted, so rather than try to make a feature out of a failing (“it’s not muddy, it’s warm” etc) the lab boffins got to work and developed a unique amplifier topology to provide it.
>
>
> In addition to those necessary sonic features, it is also highly desirable for the mic preamp to have switched gain controls for easy recall of settings, easy to read metering so that level decisions can be made instantly, and an input which can easily be switched between phantom powered for 48V mics and non-powered input for ribbon mics, valve mics with their own power supply, and dynamics.
>
>
> The DACS Clarity MicAmp 500 provides for all of this, and more, in an extremely cost-effective `lunchbox’ format. There is simply nothing as good as this at this price.
>
>
>
> * Single channel discrete-component-based microphone amplifier closely based on the award winning 2-channel Clarity MicAmp 2
> * Ultra-low noise, ultra-low distortion circuitry
> * Unmatched sonic realism: entirely true to the original source
> * Switched gain settings from +20dB to +64dB (plenty to use with low-output ribbon mics) in 4dB steps, with a 0dB to +8dB trim control
> * An input that can be phantom powered but which can also be switched to bypass the input capacitors and be coupled directly to the gain stage, for ribbon, valve and dynamic mics
> * Flat frequency response from below 20Hz to above 45kHz
> * Three-segment LED display with PPM ballistics and a bright overload LED for clear metering
>
>
> The Clarity MicAmp 500 produces an extraordinarily clear, detailed, and dynamic sound for recording everything from naturalistic voice and acoustic instruments to high-energy percussion (when utilising the robust input stage and optional in line pad).
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Crane Song Syren

**Crane Song Syren** is a pre-amp for the 500 series.

## Official description

>
> SYREN is a classic sounding tube preamp in a 500 series package, using a dual triode circuit with a 12AX7 tube
>
>
> SYREN features a dual gain stage circuit and allows overdrive effects. A switch selectable HI-z input is included. The low cut filter is at 90 Hz and is 24 db/ octave. 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 it is a more accurate audio path with wider frequency response and without negative feedback it has a more open warmer sound.
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Ovie Audio MPA2

**Ovie Audio MPA2** is a pre-amp and EQ for the 500 series, manufactured by Ovie Audio.

## Official description

>
> Preamplificador de micrófono para serie 500.
>
>
> Ecualizador de balance diferencial integrado en la preamplificacion.
> Modo linea convierte la entrada de microfono en niveles e impedancias de linea para poder pasar señales ya grabadas. El ecualizador y todos sus transformadores siguen estando en el circuito en modo linea tambien.
>
>
> Cuenta con pad de entrada de -20dB y tambien con pad de salida -20dB, lo que lleva a la generacion de distintos colores y distorsiones armonicas.
>
>
> Internamente su transformador de salida puede ser jumpeado en doble bobinado o triple, lo que junto con el pad de salida nos da muchas mas opciones de sonido.
>
>
>
> * Gain, Phase y Phantom
> * EQ balance diferencial tipo shelving a partir de 2K
> * PAD -20dB de entrada
> * PAD -20dB de salida
> * Entrada frontal de instrumento activa de alta impedancia
> * Led indicador de señal
> * Dos años de garantia
>
>
>
Rascal Audio Two-V

**Rascal Audio Two-V** is a dual pre-amp for the 500 series, manufactured by Rascal Audio.

## History

The Rascal Audio Two-V was released in 2013.

## Official description

>
> The Rascal Audio Two-V is a remarkable, dual-channel, 500 Series microphone amplifier built to fully satisfy the most discerning professional who craves vintage tone, but requires more than a one-trick pony. A true desert-island microphone amplifier for tone-lovers, the Two-V couples a deceptively simple yet uniquely powerful gain structure with dynamically responsive, Class A gain blocks to produce what is simply the most inspiring and tonally flexible, discrete, transformer-balanced microphone amplifier on the market. And above all, its tone is musical! Whether it's producing fluid, articulate gain for your guitar amps, classic British, Class A bulk for your drums, or pure buttery silk for your lead vocal, the Two-V from Rascal Audio delivers gorgeous, engaging, opulent tone every time.
>
>
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>

## References

1. ↑ https://www.gearslutz.com/board/product-alerts-older-than-2-months/800991-rascal-audio-two-v-500-series-2-ch-mic-pre.html
Wunder Audio Allotrope

**Wunder Audio Allotrope** is an equalizer for the 500 series, manufactured by Wunder Audio.

## History

The Wunder Audio Allotrope was released in 2012.

## Official description

>
> The Wunder Audio Cobalt Pre and the Wunder Audio Allotrope EQ are the result of years of testing, development and enhancements made by Wunder Audio in Austin, TX with the PEQ1 and PEQ2. The inside of these discrete Class A build-quality modules is pristine, with meticulous wiring and impeccable soldering. Top-of-the-line components are used at every junction, highlighted by our own custom wound transformers. The transformers are made using the same custom laminations of Nickel/Iron/Cobalt that were used in the original Zeppelin "Allotrope" modules; which inspired the original Wunder Audio PEQ1. The transformers are so beefy that they barely fit in the unit's case.
>
>
> Wunder Audio Allotrope EQ -
>
>
> The Wunder Audio Alloptrope EQ is a classic inductor-based baxandall equalizer with has the same EQ circuit as the Wunder Audio PEQ2. All aspects of this design from the metalwork to the components in the circuit are made to the same exacting standards as the PEQ2 simply remade for the 500 series format.
>
>
>
>

## References

1. ↑ https://www.gearslutz.com/board/product-alerts-older-than-2-months/781025-wunder-audio-allotrope-eq.html
FiveFish Audio SK-1DI

**FiveFish Audio SK-1DI** is a pre-amp for the 500 series, manufactured by FiveFish Audio.

The SK-1DI has the same audio path as the FiveFish Audio SC-501 module.

## Official description

>
> **SK-1DI Mic Preamp + DI Kit**
>
>
> *500 Series Module. Low-noise, transparent, solid bottom end, smooth highs with well-defined mids. Great for 1st time kit builders*
>
>
> The SK-1DI is a 500 Series Mic Preamp with built-in DI input. It is based on our popular SC-1 Mic Preamp Kit, with an added Direct Inject (DI) circuitry for high-impedance signal sources like electric or bass guitars. It is a clean, "fast", clear, low-noise, high-gain preamp. Its sound is very transparent, offering a flat response, smooth highs and well-defined mids.
>
>
> This is a great project for a first-time beginner to kit building. The kit is very affordable, but don't let it's low price fool you. This preamp delivers top-notch performance.
>
>
> An API Rack/Lunchbox or compatible rack is required to supply power and the necessary XLR input and output connections to the SK-1DI module.
>
>
>
> * 500 Series format, for use with API rack/lunchbox or compatible rack
> * Precision Laser cut tinted/transparent front panel - included! So you can show-off the "guts" of your DIY build
> * Aluminum sled carrier - Included!
> * Knobs - Included!
> * Actually... everything is included! Spacers, screws, nuts, and all parts to build a working SK-1DI Mic Preamp + DI Module
> * All solid-state design, using chipsets from THAT Corp and Burr-Brown
> * Soft-start, slow ramp-on +48V phantom power
> * Simple to use Gain control, up to +72dB
> * Robust 48Volt short circuit protection (from accidental phantom power shorts)
> * LED indicators for phantom power, -20dB pad, polarity reverse and Mic/DI input
> * Relay controlled Pad
> * Relay controlled Polarity Reverse
> * Built-in DI 1/4" jack inputs for electric and bass guitars
> * Electronically balanced input and output stages with option to use Output Transformer
> * Input RFI protection
> * Input clamping protection
> * Output surge protection circuit
> * Output RFI protection
> * Gold-plated, machined, low-profile IC sockets
> * Use of high quality 1% Metal Film resistors, and high-quality ceramic and electrolytic capacitors
> * Easy to assemble, easy to troubleshoot design
>
>
>

## References

1. ↑ http://www.fivefishstudios.com/500serieskits/sk1di/
JLM Audio Dual Amp Head

**JLM Audio Dual Amp Head** is a re-amping module for the 500 series, manufactured by JLM Audio. The module can only be used in the JLM Audio Eleven Rack.

## Official description

>
> Dual AMP HEADphone module fits in the spare half module space on our JLM Audio ELEVEN racks. Uses left and right TRS on rear for in and out loop. You can fit a lot in 19mm wide.
>
>
> Note: This module only fits in the extra 1/2 slot in our ELEVEN Rack.
>
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>
IGS Audio Rubber Bands 500 Mastering EQ

**IGS Audio Rubber Bands 500 Mastering EQ** is an EQ for the 500 series, manufactured by IGS Audio.

## Official description

>
> RB500ME is a stereo passive equalizer packed into a double 500-series module. This beast is equipped with transformer balanced inputs (Carnhill) and outputs (Edcor) as well as a class-A driver circuit. Of course the entire filtering section is passive and it mirrors analogue equalizers from the 60s. There is separate frequency selector for low cut and boost sections. Top quality potentiometers and ELMA switches were used to achieve outstanding performance.
>
>
> **The first ever Stereo Pulteq-style EQ in 500 format.**
>
>
> The Rubber Bands is a wonderful tool that can add multiple levels of color to any track or mix. The best thing about, it is that you can set it up in various ways, all sounding clearly distinctive and great at the same. This is the device that gives the studio engineer an opportunity to add their own personality to the music.
>
>
>
>

## External links

* Official product page
* Review in *Sound on Sound*
Joemeek preQ

**Joemeek preQ** is a pre-amp for the 500 series, manufactured by Joemeek.

## Official description

>
> 500 Series Mic Preamp with 48V Phantom Power, 20dB Pad, Optical De-esser, Variable Hipass Filter, and Front-panel High-impedance Instrument Input
>
>
> The Joemeek preQ 500 Series Mic Preamp does it all. Designed and crafted in the same spirit as Joemeek's acclaimed rack gear, the preQ 500 gives you everything you need in a mic pre. You get 60dB of clean gain, plus essential features like 48V phantom power, a 20dB pad, and phase reversal. But here's where it gets interesting - the preQ includes an optical de-esser, a variable hipass filter, and a front-panel high-impedance instrument input. Quite right. A high-quality US-made Cinemag transformer adds to the Joemeek preQ 500's unique sound.
>
>
> **Some Key Features:**
>
>
>
> * The vibrantly transparent sound of Joemeek's renowned mic preamps in a 500 Series module
> * Optical de-esser lets you control sibilance
> * Variable highpass filter lets you roll off rumble and other unwanted low frequencies
> * Instrument DI adds flexibility to your rig
> * US-made Cinemag transformer adds to the Joemeek preQ 500's unique sound
>
>
>

## References

1. ↑ https://www.gearslutz.com/board/product-alerts-older-than-2-months/805761-namm-joe-meek-500-series.html
BAE 312B

**BAE 312B** is a pre-amp for the 500 series.

## Official description

>
> The 312B Signature Series carries the same excellent dynamic range, frequency response and noise performance the BAE 312 series is known for, but with a newly introduced and modified gain structure which utilizes 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.
>
>
>
> * 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.
>
>
>
DAV BG 501

**DAV Electronics Broadhurst Gardens 501** is a pre-amp for the 500 series, manufactured by DAV Electronics.

## History

The DAV Electronics BG 501 was released in 2008.

## Official description

>
> A.P.I. 500 series microphone amplifier with DI Input.
>
>
> The features of this microphone amplifier consist of low noise and low distortion. It offers switched gain controls for high accuracy level setting (4 dB steps), D.I. Input (high impedance), level indication, 26dB pads (switchable), phase reversal and 48v phantom supply (switchable).
>
>
>
>

## References

1. ↑ https://www.gearslutz.com/board/product-alerts-older-than-2-months/350091-dav-electronics-bg501.html
Daking Mic Pre 500

**Daking Mic Pre 500** is a pre-amp for the 500 series.

## Official description

>
> Daking’s Mic Pre 500 is a redesigned version of a single channel from their popular Mic Pre IV in a module format for use in 500 Series racks. Like the Mic Pre IV, the Mic Pre 500 uses a Jensen input transformer, Class A, discrete transistor circuitry. The Mic Pre 500 uses a tri-color LED metering setup and accepts both line and hi-Z inputs via the 1/4″ jack, equipped with +48V phantom power. With a -20dB pad for added versatility, the Mic Pre 500 microphone preamplifier is ready for anything. The front panel controls include a variable high-pass filter (with a range of 10-200Hz @ 12db per octave) as well as continuously variable input gain. It also includes an eight-segment tri-color LED meter with simultaneous VU and Peak.
>
>
> Features:
>
>
>
> * Jensen input transformer
> * Class A, discrete transistor circuitry
> * 70db of gain
> * 8 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.
>
>
>
Bizzar Audio Mint Julep

**Bizzar Audio Mint Julep Mic Pre** is a pre-amp for the 500 series, manufactured by Bizzar Audio.

## History

The Bizzar Audio Mint Julep was released in 2008. Bizzar Audio "*sold a few*", but it appears not to have been produced in any great numbers. Production of the module appears to have ceased in late 2008.

## Official description

>
> The Mint Julep is a high gain mic pre with a discrete front end that is electronically balanced throughout using high quality components like the Grayhill gain switch, 1% metal film resistors, Low ESR long life electrolytic caps, WIMA coupling capacitors & unique power distribution.
>
>
> The pre is capable of up to 66dB's of gain in steps of 6dB's for accurate recall and also features a gentle active low cut filter at 100Hz, Polarity inversion and of course +48V phantom power. In addition we have added a metering circuit to round off the package, which was designed/built using the guidelines set out by the API VPR Alliance.
>
>
> Inspired by an early British design it complements the large selection of 'coloured' 500 series mic pres by offering something that is clean, open and transparent.
>
>
> All opamps are socketed and user serviceable/swappable with pin compatible chips eg TL072, NE5532, OPA2604 etc. We really like the sound of the 'classic' 5532 in this application, but a Burr Brown option will be available for the front end, for those wanting a silkier top end response.
>
>
>
>

## External links

* Review at pan60.com
* Interview at pan60.com

## References

1. ↑ https://www.gearslutz.com/board/product-alerts-older-than-2-months/230712-gearslutz-mint-julep-special-offer.html
2. ↑ http://groupdiy.com/index.php?topic=26994.0
3. ↑ https://www.gearslutz.com/board/product-alerts-older-than-2-months/167200-bizzar-audio-mint-julep-500-series-mic-preamp.html
Empirical Labs DocDerr

**Empirical Labs DocDerr** is a pre-amp, compressor, equalizer, and tape emulation module for the 500 series, manufactured by Empirical Labs.

## History

The Empirical Labs DocDerr was released in 2011.

## Official description

>
> One of the newer members of the Empirical Labs family is the DocDerr, a 500 series multi-purpose tone enhancement module that houses six different sections of digitally controlled analog processing. With over two years of meticulous development and testing behind it, the DocDerr provides an unprecedented combination of power and musicality in a compact, easy to use format. Empirical Labs' first compressor in the API 500 format.
>
>
> An extremely low-noise preamp capable of working with line level or instrument level signals, is followed by four sections of EQ combining a two position high pass filter with three parametric bands, each with its own set of carefully tuned frequency presets. An internal jumper can turn the DocDerr into an unparralled instrument preamp with 16dB of gain, ideal for acoustic guitar, bass, synths, exotic plucked instruments, etc.
>
>
> The versatile EQ is followed by a unique dynamics section which offers renowned Empirical Labs compression at an unprecedented price, and an extremely musical tape emulation circuit that softens and tames high frequencies and transient spikes. We believe it’s the best single knob “knee” compression available in this format.
>
>
> One of the pivotal features of the DocDerr is the “Mix” knob which allows the user to blend the uncompressed EQ’s signal with the compressed and saturated signal. This parallel compression technique, used by top recording and mixing engineers for many years unlocks a whole world of sonic possibilities.
>
>
> Like all ELI 500 series modules, the EL-Rx is available with either horizontal or vertically oriented front panel configurations, and is “Linkable” for using our famous compression on stereo sources.
>
>
> The DocDerr is ideal for tracking, for fine-tuning tracks during mixing, or as a killer solution for the gigging "acoustic" musician in search of studio quality tone control. It is indeed a Tone Doctor…err… DocDerr.
>
>
>
>

## References

1. ↑ https://www.gearslutz.com/board/product-alerts-older-than-2-months/622101-empirical-labs-docderr-module-api-500-series.html
Bereich03 Audio Passive-Mid

**Bereich03 Audio Passive-Mid** is an EQ for the 500 series, manufactured by Bereich03 Audio.

## History

The Bereich03 Audio Passive-Mid was released in 2015.

## Official description

>
> Passive-Mid:
> This is a passive EQ with two Boost bands and one cut band. The curves are very broad.
>
>
> All three bands are based on custom-made Inductors with an discret OpAmp for the gain.
>
>
> There are two options for the discret OpAmp. The first is a more modern designe and the second is
> a more vintage, very simple designe with much more harmonics.
>
>
>
>

## References

1. ↑ https://www.gearslutz.com/board/new-products-coming-soon/999755-musikmesse-2015-modular-mastering-desk-bereich03-audio.html
Avedis Audio MD7

**Avedis Audio MD7** is a pre-amp for the 500 series.

## Official description

>
> All discrete op-amp based preamplifier with Jensen® Transformers, Send and Return/DI for adding external effects.
>
>
>
> * Standard 500 series modular size 1.5″ x 5.25″
> * Gain range from 0dB – 64dB in 4dB steps for recall-ability
> * Input Trim control for fine control of gain
> * TransDrive™ circuitry for slight saturation at peaks
> * Utilizes the discrete 1122 op-amp known for depth and resolution
> * All discrete design with Class A buffer amplifier
> * Wide bandwidth, high headroom, very low noise
> * NO PAD, NO IC’s, and NO Surface Mount Components
> * Line Input to interface with DAW’s
> * Phase reverse, and filtered 48V phantom power
> * High Pass Filter using a gentle slope for natural bass roll-off (-3dB @ 80Hz)
> * 10 Meg-ohm high impedance DI input great for all instrument pickups
> * SEND feature to run signal through stomp boxes for variety of effects
> * Perfect for using as a re-amplification device
>
>
>
BAE 1073D

**BAE 1073D** is a pre-amp and equalizer for the 500 series.

## Official description

>
> The 1073D (Deluxe) is essentially a 1073 module with extra high frequencies and a direct input for the 500 series market. Built using the same exact parts as the 10 series module, the 1073D features Carnhill transformers, Elma gold plated switches and Canford wire making this the best sounding Class A mic‐pre EQ module on the block.
>
>
> Because BAE did not want to compromise, the parts are such that they made this a 3 space wide module for optimal quality in contrast to building a smaller rack space version lacking the same premium components.
>
>
>
> * High Frequency: +/-16dB fixed frequency shelving at 10kHz, 12kHz and 16kHz
> * Low Frequency: +/-16dB shelving with selectable frequencies of 35Hz, 60Hz, 110Hz & 220Hz
> * Mid Range: +/-18dB peaking, fixed 'Q' with, selectable centre frequencies of 0.36kHz, 0.7kHz, 1.6kHz, 3.2kHz, 4.8kHz & 7.2kHz
> * High Pass Filter: 50Hz, 80Hz, 160Hz & 300Hz
> * Phase Button: 180°
>
>
>
SM Pro Audio JuiceRack 1

**SM Pro Audio JuiceRack 1** is a 1-slot rack for the 500 series, manufactured by SM Pro Audio.

## History

The SM Pro Audio JuiceRack 1 was released in 2013 releases. By 2016, it was discontinued.

## Official description

>
> JuiceRack1 is a single-slot power source for operating one 500-series module. The back panel includes both balanced XLR and unbalanced 1/4” inputs and outputs; a 48V phantom power switch is located on the front. JuiceRack1 is a half-rack format, and includes a connector that allows two units to be mounted into a single 1u 19” rack.
>
>
> Features all-metal construction and full compatibility with the 500-series format. The external AC power supply design, which keeps the power transformer separated from your 500 module’s sensitive electronics, ensures reduced hum and signal interference.
>
>
> Our JuiceRack 1 power supply produces more current than any other 500 series power unit on the market today. So you can be confident that any brand of 500 series module will be powered correctly in your SM Pro Audio JuiceRack 1.
>
>
> The power output (in milliamps) for the JuiceRack 1 is as follows: Juicerack 1 = 600mA
>
>
> The original API™ spec calls for an average of 130mA for each slot, but there are 500 series modules from many manufacturers that require more power than that average. SM Pro Audio ensures that you can easily power any 500 series module available today with our JuiceRack 1 power supply.
>
>
>
>

## References

1. ↑ https://www.gearslutz.com/board/product-alerts-older-than-2-months/806268-namm-sm-pro-audio-4-new-500-series-racks.html
2. ↑ https://www.gearslutz.com/board/so-much-gear-so-little-time/1083922-500-series-rack-pick-one.html
Bereich03 Audio Monitor-Controller

**Bereich03 Audio Monitor-Controller** is a monitoring module for the 500 series, manufactured by Bereich03 Audio.

## History

The Bereich03 Audio Monitor-Controller is still (as of 2016) only a protoype. It is the only known 4-slot module for the 500 series.

## References

1. ↑ http://www.bereich03-audio.de/bereich03-audio/Mastering-MonitorController.html
Helios Type 69-500

**Helios Type 69-500** is a pre-amp and equalizer for the 500 series, manufactured by Helios Electronics.

## History

The Helios Type 69-500 was released in 2011.

## Official description

>
> The Helios Type 69-500 500 Series module holds true to the original Dick Swettenham design, but with a number of modern updates such as 5db steps on the mic preamp gain switch as opposed to the original 10db steps, additional 16khz EQ frequency selection for today's high-bandwidth digital recordings, and a balanced output for easy interfacing with any digital converter.
>
>
> The Helios Type 69 Mic Pre/EQ Module is reborn!
>
>
> Re-manufactured classic three-band mic pre/EQ. Discrete. Switchable lo/mid. Fixed top. Hi-pass. Unlike anything you have ever used (especially if you are stuck in API-Neve land). You will find the Type 69 a unique departure. These hand-built units have a Sowter input transformer based on the highly desirable Lustraphone (Olympic) transformer models. The mids are so funky and sweet – guitars and snare drums from heaven; woody and sweet! 700 to 2k to die for! Lows are reminiscent of Pultecs. Highs are sweet and musical. An extremely open mic pre; in mic shootouts, these are as open as the king daddy Telefunken V76m. Transform your life!
>
>
> The legendary Helios Electronics Ltd. has resurrected with much anticipation and patience, the Olympic Type 69 Series EQ as used by the Beatles, Rolling Stones, Bob Marley, Led Zeppelin and so many others. In its heyday, Helios became known as the musician's choice of recording consoles.
>
>
> Brought in line with modern expectations, these units are built to military specifications with supervision of gear fanatic and music producer Tony Arnold. Endorsed by the late Dick Swettenham, of the original Helios Electronics Ltd., to maintain and service all of the original consoles, Tony later purchased the original company, including all of its circuits and parts.
>
>
> The modern circuit is similar to the original, aside from one vast improvement - the build quality and reliability. The openness and clarity has been upheld, with the addition of EQ frequency selections. Tony Arnold explains, "We asked many of the original users of the Helios desks what they felt was missing and if we could make any improvements. Most wanted the 30Hz added to the Low EQ. In order to meet today’s CD standards, some wanted a tight high frequency around 16k, which has been added without changing the original Helios sound whatsoever."
>
>
> "WON'T GET FOOLED AGAIN was recorded on the Stones mobile using 69s. These modules are the ones that re-create the sound I remember. On acoustic guitar a little 10k and 2.4, and a slight bass cut with a Neumann U87 and there is Glyn Johns 1970. Straight out of the box. It's spooky."
> Pete Townshend
>
>
>
>

## References

1. ↑ https://www.gearslutz.com/board/product-alerts-older-than-2-months/669075-helios-type-69-mic-pre-eq-part-company.html
Ovie Audio mini500

**Ovie Audio mini500** is a 2-slot rack for the 500 series, manufactured by Ovie Audio.

## Official description

>
> * Gabinete serie 500 de 2 canales
> * Ideal para dar el primer paso en serie 500
> * Muy transportable
> * Cuenta con transformador externo para eliminar todo tipo de ruido inducido slots cercanos
> * Jumper de link stereo
> * Piezas de sujecion para rack convencionales
> * 240mA por rail permite un amplio margen de corriente para instalar cualquier tipo de modulo
> * 2 años de garantía
>
>
>
Chandler Limited Little Devil Pre Amp

**Chandler Limited Little Devil Pre Amp** is a pre-amp for the 500 series.

## Official description

>
> We've been told by beta testers that this might be the best piece of Chandler gear yet! What makes the Little Devil Pre so special? Well, several things.
>
>
> The Class A gain stage sounds like no other design we've done. It's big, yet open and full of life. Just about any parameter of the sound is changeable including the ability to change both the Feedback and Bias of the amplifier. The Feedback control increases harmonics thousands of times over the range of the control. The nature of clipping and distortion also changes and ranges from soft Class A clipping to super soft gushy tube type. The sounds range from a very colored and "overbiased" tone to a gently colored and "in your face" tone.
>
>
> Other features of the Little Devil Pre include High and Low input impedance; transformer balanced line in for using the Devil as a color box on mixes or tracks; low cut; bright switch and more! This unit has no power-up issues with lunchboxes and rack systems.
>
>
> LITTLE DEVIL PRE AMP TECHNICAL SPECIFICATIONS
>
>
>
> * FORMAT: 500 Series
> * CHANNELS: Mono
> * CIRCUIT: Class A, Discrete, Transistor
> * GAIN: max 66.5db
>
>
> CONNECTIONS
>
>
>
> * I/O: 500 Series Enclosure
> * Mic Input, Transformer Balanced, Input Impedance: 300 Ohm or 1200 Ohm
> * Line input, Transformer Balanced, Input Impedance: 10k
> * DI: 1/4" Unbalanced
>
>
> PHANTOM POWER: +48v
>
>
>
>
AL.SO M26

**AL.SO M26** is a summing module for the 500 series, manufactured by AL.SO.

## History

The exact year of release of the AL.SO M26 is unknown (and if it ever reached the market). At Gearslutz, the year of release was announced as 2007. However, another press release appears to give the year of release as 2009.

## Official description

>
> 26 x 2 Summing Module Including insertions pathes
>
>
> Designed to work in standard "500" racks.
>
>
> Specs:
>
>
>
> * 10Hz to 120 kHz +/- 0,2dB
> * THD at 16dBu, 2ch: 0,002 %
> * Xtalk, 1kHz,+16dBu better than -96 dB
> * Maximum input level for 1% distorsion: +26dBu
> * Permits to compress drums separately and to compress differently the main mix
> * Main mix insertion and output level control
>
>
> Special feature: Sigma Bus trim in order to have the best level and avoid mix amp saturation when inputs are high level and correlated.
>
>
>
>

## References

1. ↑ https://www.gearslutz.com/board/product-alerts-older-than-2-months/331203-al-so.html
2. ↑ 2.0 2.1 http://www.macmusic.org/news/view.php/lang/en/id/7940/
Big Bear Audio MP1+

**Big Bear Audio MP1+** is a pre-amp for the 500 series, manufactured by Big Bear Audio.

## History

The Big Bear Audio MP1+ was released in 2016.

## Official description

>
> The MP1+ is a statement of electronic and aesthetic design. It has been designed from the ground up to provide producers, recording and mix engineers of every level with an innovative and intuitive Colour amplifier.
>
>
> The Colour platform created by DIY Recording Equipment pathed the way for affordable analogue distortion, the MP1 takes this platform further combining a low noise discrete mic pre with a high impedance discrete Instrument input.
>
>
> The MP1 is not a clone. It has been designed from scratch to provide engineers with a world class discrete Class A recording amplifier with the ability to add any Colour they choose.
>
>
> Features
>
>
>
> * Discrete Class A Mic/Line Amplifier
> * Interchangeable DIYRE Colour Slot
> * Discrete Instrument Input
> * Lundahl Output Transformer
> * ELMA Stepped Attenuator
> * Audio Grade Capacitors
>
>
>

## References

1. ↑ https://www.gearslutz.com/board/aes-2016-los-angeles-ca-usa-sep-29-oct-2-los-angeles-convention-center/1115238-big-bear-audio-mp1.html