Eurorack Reference

ALM Busy Circuits / alm-busy-circuits/mfx

MFX

Compact 6HP Eurorack stereo digital audio multi effects processor offering 17 different full featured effects programs plus a number of metering utilities. [20]

Specifications

HP
6
Depth
32 mm
+12V
50 mA
−12V
15 mA
+5V
—
Last verified
2026-05-02

Capabilities

  • CV Control cv-control
    3 freely assignable CV inputs (0-5V), 1 clock/trigger input; each CV assignment includes digital attenuation and offset; expandable to 7 CV inputs via AXON expander [20]
  • Multi Effects Processor multi-effects-processor
    17 effects programs including delays, reverbs, distortion, dynamics, modulation, granular and glitch effects plus metering utilities [20]
  • Preset Storage preset-storage
  • Stereo Processing stereo-processing

Jacks (8)

Inputs (6)

NameSignalVoltageDescription
CV1 cv 0V to 5V [20]
CV2 cv 0V to 5V [20]
CV3 cv 0V to 5V [20]
Clk clock — [20]
Left Input audio ≤16V [20]
Right Input audio — [20]

Outputs (2)

NameSignalVoltageDescription
Left Output audio — [20]
Right Output audio — [20]

Parameters (21)

NameTypeRangeMin FWBehavior
2051 Bit Corrupter menu_setting — — Real-time glitch/stutter buffer. Mono or Stereo In → Mono or Stereo Out. Modes: Mono (max 1000ms), Stereo (max 500ms, same random seed), Dual (max 500ms, different random seeds). Parameters: Bit Depth, Sample Rate, Buffer Size, Max Repeats, Chance, Lock In, Reverse, Fade In, Mix Type (PRE/PST), Clock, Clock Mult. [20]
Almicon Reverb menu_setting — — 80s studio style reverb. Stereo In → Stereo Out. Parameters: Size, Damping, Diffusion, Pre-Delay (0-99ms), Era (80s lower bit depth vs NOW higher resolution). [20]
Crumbular Echo menu_setting — — Granular multi-tap delay. Mono or Stereo In → Mono or Stereo Out. Parameters: Time (50-999ms), Mode, Spray, Shape, Density, Recycle, Feedback, High Cut, Low Cut, Burst. Clock input triggers a burst of grains when Burst is ON. [20]
Digi-PCM Echo menu_setting — — Digital delay with external clock sync and 5 delay modes (Mono Delay, Dual Tap, Stereo Tap, Ping Pong, Ext Feedback). Parameters: Mode, Clock, Time (0-998ms x8), Clock Mult, Tap Mult, Bandwidth, Bit Depth, Mod Depth, Mod Rate, Regen, Flip Phase, Reverse, High Cut, Low Cut. [20]
Ensembles Ensemble menu_setting — — Chorus and ensemble collection. Mono In → Mono or Stereo Out. Modes: Juno I, Juno II+I, Alpha, RS I, RS II, Solina (mono), Wide, Vibrato. Parameters: Depth, Pitch Shift, Mod Rate. [20]
Mix menu_setting 0% – 100% — Sets the wet/dry blend of the effect with the original input source. At 0% only dry signal is heard; at 100% only the affected signal remains. Can be disabled globally from Utilities to lock all effects to 100% wet. [20]
Modulating Panner menu_setting — — Clock-syncable auto-pan. Modes: Mono (pans left input L/R), Stereo, Scan (cross-fades between L and R inputs to mono). Parameters: Mod Rate (0.05-8Hz internal), Mod Clock (INT/EXT), Offset, Shape, Width, Filter Mode, Cutoff (20-20kHz), Resonance. [20]
Multi Phaser menu_setting — 103+ Multi-stage phaser. Mono or Stereo In → Mono or Stereo Out. Modes: Mono (up to 8 stages), Stereo (up to 4 stages), Infinite Up, Infinite Down. Parameters: Depth, Mod Rate, Feedback, Stages (2-8 mono / 2-4 stereo), Spread, FB Comb. [20]
Pocket PL8 Reverb menu_setting — — Early digital plate reverb. Mono In → Mono or Stereo Out. Parameters: Size, Tightness, Stereo, Reverse, Pre-Delay (0-99ms), Freeze. Clock input gates reverb tail (or refreezes if freeze active). [20]
Preset menu_setting — — Allows initialising, loading and saving effect parameters into up to 32 numbered user preset slots shared between all effect programs. Factory presets are also available per effect. [20]
Program knob — — [20]
Quaidra Reverb menu_setting — — 90s style reverb excelling at large airy spaces. Stereo In → Stereo Out. Parameters: Size, Damping, Low Cut, Era (90s lower bit depth vs NOW higher resolution). [20]
Ring + Freq Modulator menu_setting — — Ring modulation and frequency shifting in true stereo. Mono or Stereo In → Mono or Stereo Out. Ring Mod params: Modulator (INT/LxR), Osc Rate (20Hz-11kHz). Freq Shifter params: Shift (0Hz-1kHz), High Cut, Env Follow. [20]
Slinky Reverb menu_setting — 108+ Spring type reverb emulation. Mono In → Mono or Stereo Out. Parameters: Length, Damping, Brightness, Wide. [20]
Squoval Rezonator menu_setting — 106+ Dual-mode resonator: 8 band mono or 4 band true-stereo. Mono or Stereo In → Mono or Stereo Out. Parameters: Base Freq, Ratio, Resonance, Num Active (1-8 mono / 1-4 stereo), Reflects, Max Frequency, Mode, Stereo. [20]
TH-30 Distortion menu_setting — — Versatile distortion. Stereo In → Stereo Out. Types: Soft (analog soft clipping), Overdrive, Wavefold (digital wavefolder), Nuclear (maximum clipping), Warm (tube style). Includes a tilt filter and output level control. [20]
TY-50 Dynamics menu_setting — 110+ Multi-mode dynamics processor. Stereo In → Stereo Out. Modes: Stereo Compressor, Sidechain in R, Transient Shaper, Stereo Expander. Compressor params: Threshold, Ratio, Attack, Release, Make Up Gain. Transient Shaper params: Attack, Release, Tilt Filter, Make Up Gain. Clock input 'ducks' the compressor. [20]
Tape-Tech Echo menu_setting — — Analog tape style delay with pitch shifter. Mono In → Mono Out. Parameters: Time (0-998ms), Feedback, Pitch Shift, Tape Age, Pitch Destination, Loop, Wow+Flutter, Clock, Play Heads, Clock Mult. [20]
Ursa Minor Echoverb menu_setting — — Complex multi-tap delay configurable as reverb or echo with 20 different programs (time arrangements for 8 delay taps). Stereo In → Stereo Out. Parameters: Mode, Time (0-254ms in echo mode), Program (20 tap arrangements), Feedback, Tap Level 1-4, High Cut, Low Cut. [20]
Utilities menu_setting — — Utility program with pages: Tuner (Hz and pitch/cents), Test Tone (off/440Hz A/261.6Hz C), Clock Meter (BPM/pulse count/width via Clk input), Scope (waveform viewer), Analyser (spectrum to 5kHz), Wet/Dry Mix (global mix disable), FW Version display. [20]
Yetti Reverb menu_setting — 103+ Feedback delay network reverb with 4 octave pitch shifter. Stereo In → Stereo Out. Parameters: Size, Damping, Pre-Delay (0-100ms), High Cut, Low Cut, Pitch Shift. [20]

Firmware history (15 versions)

VersionReleasedNotes
115 — Added NEW Stereo Expander mode to TY-50 Dynamics. Mix control enabled for both Transient Shaper and Sidechain In R modes. Added NEW Fade In parameter to Bit Corrupter. Added NEW FB Comb parameter to Multi Phaser. [20]
114 — Improved filter in Modulating Panner and resonators in Squoval. Fix digi-pcm clocking bug. More preset lockup fixes. [20]
113 — Fix potential noise on some reverbs when bypassed. Fix Clock utility response. Fix potential lockups on some presets. [20]
111 — Overhaul crumbular engine; more crumbs, improved clipping. Added new 'recycle' and 'shape' parameters to crumbular. Added visualisations for spray and density crumbular parameters. Fix visual bug with the CV chart for dB parameters. Ensemble 'mod rate' parameter made CV-able. Added wide mode for spring. Added new distortion type 'warm'. [20]
110 — Added NEW 'PRESET LOADER' screen. Merged Transient Shaper and Compressor engines into NEW 'TY50 Dynamics'. Added NEW stereo Ensembles Ensemble modes (Vibrato, Rotary, Alpha). Improved Tape Echo with much improved tape aging and wow & flutter. Improved Pocket Pl8, Almicon and Yetti verb Pre-Delay parameter. [20]
109 — Fix Axon UI slow down bug. [20]
108 — Added NEW 'Slinky' spring reverb engine. Added NEW high res modern Quaidra & Almicon reverb implementations. Added NEW shared global user presets (no longer 2 per fx user preset limit). Spectrum Analyser display minor improvements. [20]
107 — Added NEW spectrum analyser to utils. Added NEW 'Freeze', 'Reverse', and 'Tightness' params to pl8 reverb. Fixed test tone in utils. Fixed Bit Corrupter sometimes initialising incorrectly. Fixed Digi Delay sometimes initialising incorrectly. [20]
106 — Added new Resonator FX engine. Added 'infinite' modes to Phaser. Added PRE/PST parameter to glitch to control mix. Added many new 'basic' static presets to most engines. Fixed a bug with parameters loading incorrectly from presets. [20]
105 — All Reverbs (except pl8) now perform the final mix with stereo input. Crumbular delay in stereo mode now final mixes with stereo input. Digi-delay parameter loading fixed. External clocking accuracy improved. Axon 2 support (Tap tempo / Toggle passthru). [20]
104 — Introduced MFX to VCV Rack. Fixed lockup in 2051 Bit Corrupter with ext clock and stereo mode. Improved external clocking stability in Tape Delay. Axon CV assignments now save correctly across power cycles. Added presets from Mumdance. [20]
103 — Added Yetti FDN Reverb engine. Added Multi Phaser engine. Reworked Crumbular Echo. Added state variable filter to Modulating Panner. Added sidechain mode to TY-50 Compressor. Added stereo and dual modes to 2051 Bit Corruptor. [20]
102 — Added global wet/dry mix control to Utilities. Added envelope follower toggle to Frequency Shifter. Added clock metering utility page to Utilities. Fixed Frequency shifter param names. Added extra headroom to Frequency shifter & Ring mod. [20]
101 — Fix CV handling range on certain params. Add toggle param for pitchshifter dest on Tape Delay. Disable CV on some reverb pre delays to avoid lockup. Fix EXT/INT clock mode switching. Add extra headroom to Quaidra & Almicon reverbs. Fix Almicon pre-delay. Odd versions considered 'beta' releases. [20]
100 — Initial release firmware. [20]

References (2)