TECHNICAL SPECIFICATIONS
Circuit Design: Dual-stage transformerless console topology based on the 9000J Desk
Format: 500 Series (VPR Alliance & GDIY 51X compatible)
Gain Control: 16 dB to 68 dB stepped gain via high-precision Grayhill switch
Matched Transistor Input: Premium Alfa RPAR AS194H super-matched transistors (superior linearity over obsolete MAT02; fully MAT02 pin-compatible)
Output Stage: Electronically balanced via THAT 1646 IC
Output Fader: -∞ to +12 dB attenuation/boost post-preamp
Expansion: 1x DIYRE Colour Module compatible slot
Power Requirements: Standard ±16 V DC / +48 V DC (500 Series rack)
DETAILED FEATURES
Ultra-Linear 9000J Circuit Architecture:
Modern AS194H super-matched transistor front-end delivers lightning-fast transient speed, absolute clarity, and an extraordinarily flat frequency response
Active production components ensure long-term repairability and reliable channel matching across multiple units
Stepped Grayhill Gain Control: 16 – 68 dB in precise steps for accurate, repeatable recall between sessions
Output Fader (-∞ to +12 dB): Post-preamp output control gives you total gain-staging freedom before sending audio to your converter
Switchable LED Level Metering: Internal switch allows real-time signal monitoring either pre-fader or post-fader, paired with a dedicated post-preamp Peak LED
DIYRE Colour Module Compatibility: Onboard slot lets you introduce custom analog warmth, saturation, or compression to an otherwise ultra-clean signal path
Steep 24 dB/oct Sweep Filters:
Low-Cut filter: Continuously variable from 10 Hz to 250 Hz (24 dB/oct)
High-Cut filter: Continuously variable from 3.5 kHz to 20 kHz (24 dB/oct)
Complete Channel Utilities:
+48 V phantom power switch for condenser microphones and active DIs
Polarity (phase invert) switch
-20 dB input pad for hot line-level sources or high-SPL tracking
Premium Components: Built with conductive plastic potentiometers for ultra-smooth travel and maximum operational life
WHAT'S INCLUDED IN THE KIT?
This is a full DIY kit including all hardware and electronic components:
Powder-coated front panel with high-quality printing
Super-matched Alfa RPAR AS194H transistor pair
Stepped Grayhill gain switch and conductive plastic potentiometers
All electronic components (precision resistors, caps, ICs, and THAT 1646 driver)
Complete set of control knobs and hardware
(Note: Requires assembly and soldering skills. Interactive step-by-step assembly guides are available in our Build Manuals section.)
Help yourself and others in the corresponding GroupDIY Help Thread