Eurorack Reference / modules /frap-tools/cgm-master audit site v0.1 — milestone 3
frap-tools/cgm-master

CGM Master (M)

Frap Tools

The Masterone is the gateway from the modular system to the outside world, providing high-quality outputs in multiple formats including pseudo-balanced stereo TRS, balanced stereo XLR, and pseudo-balanced mono outputs, plus a headphones/PFL section.599

Capabilities 4

Audio Mixeraudio-mixer
The Masterone receives the stereo mix bus from upstream CGM Channel and Group modules via the CGM Link bus and provides the final output stage.599
CUE/PFL Monitoringcue-monitoring
PFL circuit receives PFL signals from connected channels and groups; the PFL Blend knob crossfades between main mix and PFL signal in headphones output.599
Headphone Outputheadphone-output
Dedicated headphones section with independent level control (A.27) and PFL Blend crossfader (C.5) to blend main mix with PFL signal for cueing.599
Stereo Mixerstereo-mixer
599

Jacks 6

NameSignalVoltageDescription
Outputs (6)
Balanced Output Leftaudio—Balanced XLR stereo left output. Their output will sound twice as louder as the pseudo-balanced one (+6 dB). Attenuatable by 30 dB via Line/Mic switch.599
Balanced Output Rightaudio—Balanced XLR stereo right output. Their output will sound twice as louder as the pseudo-balanced one (+6 dB). Attenuatable by 30 dB via Line/Mic switch.599
Master Output Leftaudio—Pseudo-balanced ¼" TRS stereo left output at Eurorack line level. Attenuatable by ~15dB via Line/Inst switch.599
Master Output Rightaudio—Pseudo-balanced ¼" TRS stereo right output at Eurorack line level. Attenuatable by ~15dB via Line/Inst switch.599
Mono Outaudio—Pseudo-balanced monophonic output providing the sum of left and right channels. Features an amplifying circuit with additional 6 dB of gain and 15 dB of attenuation from line level reference.599
Phones Stereo Outputaudio—Stereo headphones output jack with independent level control and PFL blend. The headphones level is independent of the main fader's level.599

Parameters 6

NameTypeRangeBehavior
Line/Inst Switchswitch—Attenuates the TRS pseudo-balanced stereo outputs by ~15 dB when set to lower position (Inst), to match instrument-level destinations.599
Line/Mic Switchswitch—Attenuates the XLR balanced stereo outputs by 30 dB when set to lower position (Mic), to match microphone-level destinations.599
Master Faderfader—Sets the overall volume of the master output. Controls the amplitude of the sum of connected groups. The Master features two columns of 12 LEDs acting as a stereo VU meter.599
Mono Out Faderfader—Controls the mono output level. Rotate left to attenuate (up to -15 dB from line level), rotate right to amplify (up to +6 dB from line level).599
PFL Blendknob—Crossfader blending the main out signal with the PFL signal for headphone monitoring. Used to prelisten channels or groups before mixing them in.599
Phones Levelknob—Sets the headphone output volume independently of the main fader.599

Firmware history 0 versions

No firmware history recorded.

References 2

  1. [599]
    Frap Tools MANUALONE (multi-module manual; M Master section)manual
    source 599 canonical ↗ archived ↗
    ⚠ verified 2026-05-21 · manufacturer changed since last verified
  2. [600]
    Frap Tools CGM Master (M) product pageproduct_page
    source 600 canonical ↗ archived ↗
    ⚠ verified 2026-05-21 · manufacturer changed since last verified