Manual PDF / Bohm Documentation
A Eurorack musician’s take on how to push Bohm beyond “just kicks”
Bohm is marketed as a stereo dual-voice kick system, but the manual makes it clear it can do much more if you treat it like a playable synth voice + rhythmic layer generator + sidechain/effects hub. The biggest takeaway is:
That means you can get: - distorted percussion - talking / tearing basslines - pseudo-pads and haunted drones - industrial tops, reese-adjacent lows, broken techno thumps, DnB stabs
Before patch recipes, here are the most important modulation facts from the manual:
This is huge. If HIT stays high, the sound sustains. That means Bohm can act more like a bass synth/drone voice than a one-shot kick.
Use this for: - bass notes - held drones - long evolving atmospheric tones - pitch-tracked lines
The manual says for proper pitch tracking:
- set PITCH knob fully CCW
- set PITCH attenuverter fully CW
- choose proper Pitch CV range in system settings: 0..1V, 1..2V, or 2..3V
- make sure sequencer is 1V/oct
This is essential for: - dubstep bass riffs - DnB subs - melodic industrial percussion - pad/drone harmonics
The pitch envelope curve moves from: - 808-style counterclockwise - 909-style clockwise
The manual notes that fully CCW reaches the fundamental frequency quicker. That means: - shorter, more solid bass pitch center - better bassline tuning - more stable held-note behavior
While clockwise can give: - more exaggerated punch / dive - more synthetic attack - more aggressive transient motion
Modulate or perform this manually for big character changes.
On many models, COLOR is not simply “brightness.” It often controls: - wavetable position - position over time - transient harmonic content - sound source blend on Groove
This is probably one of the best CV destinations for “alive” sounds.
Groove has: - its own trigger input: CLOCK - relative PITCH and LENGTH - COLOR source blending - 2 / 3 / 4 taps shaping an envelope - TAPS CV output
That means Groove can become: - a tuned secondary bass layer - a metallic top layer - an evolving rumble envelope source - a modulation generator via TAPS out
Performer has: - external stereo input - ducking on every HIT - effect modes like DJ Filter, HP, LP, Beat Roll, Slip Roll - channel selector: ALL / KICK / INPUT
This opens up a lot: - sidechained pads - pumping drones - beat-repeat resampling - filtered industrial atmospheres
Use: - FM-2X - OLP4 - VX-T - PX3 - SP-6 - WT-4
Use: - FM-2X - HZ-1 - VX-T - XT-88 - OLP4
Use: - PM-K1 - HZ-1 - VX-T - XT-88 - WT-4 - Groove + Performer together
Use a clock divider/multiplier so one modulation source changes every 2, 3, or 5 hits rather than every hit. That creates repeatable “machine language” percussion instead of chaos.
These models combine wavetable kick body and transient/sample layering. When pitch and color move together, they stop reading as a standard kick and start becoming hard-edged drum voices.
Make the FUNCTION CV randomize in Studio mode between takes. Since Bohm randomization is designed around “sweet spots,” you can quickly discover distorted percussion presets.
Groove repetitions are retriggered, not delayed copies. That means the groove voice acts like a sequenced percussion synth. With HP/BP filtering and changing tap levels, it becomes a clattery glitch layer rather than a normal rumble.
Per manual: - PITCH knob full CCW - PITCH attenuverter full CW - set Pitch CV system range properly - use 1V/oct sequencer - use longer LENGTH or hold HIT gate
This is the main unlock for turning Bohm into a bass synth.
FM-2X
FM-2X gives you: - sub carrier - modulator-driven attack/growl - wavetable-dependent tone changes - ratio variation for harmonic character shifts
Patch an LFO or envelope to ATTACK CV and sync it to phrase length. You’ll get “opening” growls on selected notes without losing low-end consistency.
On these wavetable-oriented models, COLOR often sweeps harmonic position over time. This behaves a lot like a wavetable sweep or moving tone contour. Add Performer filtering and you get pseudo-formant movement.
This gives a bass patch with: - Bohm = body/sub - Groove = grit/motion/top harmonics
That’s a very dubstep/neuro concept.
It won’t be a classic detuned dual saw reese, but it can create a similar feeling: - wide moving low-mid texture - animated upper harmonics - unstable stereo edge - filtered motion
Use Panning system settings: - Bohm hard left - Groove hard right - Performer center or one side
Now process left/right externally with separate Eurorack chains for serious stereo destruction.
This gives sharp, tuned impacts that sit between kick, bass, and tom. Great for: - jump-up stabs - techstep bass punctuation - industrial fills
This is the most non-obvious use of Bohm, but the manual directly supports it because: - HIT can sustain with a gate - PITCH can track - Performer ducks and filters external audio - Groove can create evolving envelopes and texture layers
The key is to stop thinking “kick” and think “held digital resonant voice.”
A held Bohm tone with wavetable motion can become a haunting sustained sound, especially when pitch dive behavior is minimized and the transient is tamed.
For cleaner sustained notes: - keep CURVE more toward the side that stabilizes pitch sooner - lower transient emphasis - avoid overly short LENGTH
PM-K1
This model is totally different: - PITCH = drum size/tension - ATTACK = beater volume - TRS TONE = beater reverberation decay - SUSTAIN = ambient mic volume - LENGTH = room size - FX = stereo spread of ambient mic
This can create: - ghostly resonant drum rooms - cinematic low thuds - ritual ambient percussion - almost-tom, almost-space, almost-pad textures
This is probably the fastest path in Bohm to “haunting.”
Now Bohm becomes the rhythmic ghost controlling another sound source: - the pad breathes with the kick - Groove envelope creates non-standard swells - Performer ducking gives transparent or exaggerated pumping
This is excellent for: - haunted pads behind broken beats - sidechained cinematic wash - evolving dub-techno atmospheres
Performer can stutter and resample input around hits, which turns static ambience into ghost rhythm. Great for: - dark DnB intros - haunted breakdowns - IDM-ish shattered atmospheres
The manual says TAPS output can emit: - GROOVE envelope - I BOHM inverted Bohm envelope - PERF performer envelope - BOHM Bohm envelope
This is one of the coolest features.
That’s instant haunted atmosphere.
The Groove section has: - repetition - kick reverb - noise - grit + sub
Since COLOR blends these, slow CV on Groove COLOR can morph from: - rhythmic repeat - to hiss/noise texture - to gritty low-end layer
This is extremely useful for neuro / bass music hybrid patches.
The DUCK BS variation sets a band split frequency: - lows duck - highs preserved
This is powerful and easy to miss.
For haunting pads, this is often better than full-range ducking.
Aggressive bassline with attack bark and moving upper harmonics
FM-2X
Keep Bohm as the sub/fundamental and Groove as the upper dirt.
Metallic industrial percussion line
OLP4 or PX3
This produces a line that sits between tuned drum hits and machine noise.
A sustained, wobbling dark harmonic bed
HZ-1, WT-4, or XT-88
This works best if you reduce the attack transient and let wavetable movement do the talking.
Haunted cinematic percussive ambience
PM-K1
This makes spectral low-end drum ghosts and ritual room tones.
Pad that breathes around Bohm hits
This makes the whole system feel like one breathing instrument.
Because many parameters are macro controls, Bohm responds best to musical, not purely chaotic, CV.
Use: - slow triangle / sine LFOs for COLOR and FX - stepped random for VELOCITY, ATTACK, PITCH jumps - envelopes for ATTACK and FX - burst/ratchet clocks for Groove CLOCK - sample & hold for transient tone changes - sequenced CV lanes for COLOR movement phrase-by-phrase
This means you can create families of radically different bass/percussion/pad states and recall them like presets for a set.
Use it for: - section changes in a live DnB set - switching from kick to bass drone instantly - verse/chorus transitions
If you want one control always live during performance: - set that parameter to OVR
Example: Keep COLOR on override in a live bass patch so you always have hands-on “wobble depth.”
Hard-pan: - Bohm left - Groove right - Performer center or opposite side
Then process channels separately outside Bohm. This is killer for: - stereo bass mangling - asymmetrical distortion - pseudo-mid/side destruction
Since Bohm and Groove can get very bass-heavy or harsh, Post EQ can be used like global voicing: - cut excess mud - boost bite - tame fizz
Very useful if you build dubstep/DnB patches that overload the low mids.
If I were using Bohm for your goals, I would focus on these 5 workflows:
This is the biggest key to turning Bohm into: - bass synth - drone - pad voice
Not just rumble. Use it as: - tops - grit - ghost notes - bass harmonics
Especially: - DJ FILTER - LP/HP - ducking - beat/slip roll on input or kick
On Bohm and Groove both. This is where a lot of movement lives.
It can animate the rest of your rack and make Bohm the rhythmic brain of a larger patch.
Bohm is most interesting when you stop asking it to be a kick drum and instead patch it like: - a bass voice with transient architecture - a dual-voice percussion synth - a stereo drone generator - a sidechain and resampling performance processor
If you want, I can also turn this into:
1. a set of specific patch sheets,
2. a genre-focused guide for dubstep / neuro / industrial techno / dark ambient, or
3. a “best CV inputs by model” cheat sheet.