Ohm Force Bohm Eurorack Manual
Although Bohm is presented as a stereo dual-voice kick system, the manual makes it clear that it can do much more than drum duties. Used together, Bohm + Groove + Performer can become a compact melodic bass / riff / drone / resampling / performance FX voice for Eurorack.
These modules can create melody in four main ways:
Bohm’s kick engine becomes a playable oscillator/enveloped synth when you use:
Groove as a second related melodic voice
That makes it ideal for:
Performer as a melodic processor
This means Bohm/Groove can be used as melodic sources, while Performer shapes them into playable transitions, filter sweeps, beat-roll textures, and sidechained musical layers.
Snapshots and Live modes as “preset melody states”
The most important melodic feature in the manual is here:
0..1V1..2V2..3VThis means Bohm can function as a monophonic bass synth voice over a one-octave window, depending on configuration and model behavior.
The manual says:
For melody, this is huge. It means you can send: - a gate sequence - a keyboard/gate - a sequencer with variable gate lengths
This transforms Bohm from a percussive one-shot into a sustained playable voice, especially for: - basslines - drone notes - acid-like plucks - sustained sub melodies
Even when using Bohm melodically, the kick controls become useful synth-shaping controls:
So for melodic use: - reduce transient-heavy settings for smoother notes - lengthen LENGTH - increase SUSTAIN - use HIT gate for true sustain - use COLOR and FX as musical tone controls
From the manual, these are especially promising:
Best for: - FM basslines - techno bass melodies - metallic subs - playable low-end riffs
Why: - 2-operator FM structure - ATTACK controls FM amount - TRS TONE changes modulator waveform - RATIO variation changes harmonic relationship
Musically, this can move from: - clean sine-ish bass - to punchy FM bass - to more overtone-rich melodic lines
Best for: - classic electronic basslines - smoother melodic kick-bass hybrids
Why: - wavetable oscillator + transient synth - analog-style wavetable options - variable click choices
Best for: - sharper, articulated melodic parts - percussive leads - bass + hi-click hybrid sequences
Why: - transient synth is more pronounced and tunable - can create top-heavy melodic attacks
Best for: - rounded “analog-style” melodic bass - layered, musical low-end phrases
Best for: - more aggressive melodic content - industrial / experimental riffs - textured bass hooks
Best for: - custom melodic design
Why: - load your own wavetables - load your own samples - tune BRIGHT and LAYER VOL - create a hybrid oscillator + sampled layer melodic voice
This is probably the most powerful model if your goal is to turn Bohm into a custom bass instrument.
Less useful for conventional melodic sequencing: - It is a physical model of an acoustic bass drum - many usual controls are inactive - Groove is not supported with it
Still usable for tuned tom-like or acoustic drum-pitched lines, but not the first choice for melodic work.
Groove is described as a secondary kick voice, often for rumbles or tops. But the architecture makes it very useful melodically.
Its key melodic behavior:
This means Groove is ideal for making a dependent second voice, such as:
Groove contains 4 sound generators:
Selected/blended with COLOR.
This is the most obviously melodic: - every CLOCK trigger retriggers a “tap” - these are not delayed echoes; they are fresh rhythmic retriggers - tap levels are controlled by: - 2 - 3 - 4 - TAPS CV
This can create: - bass arpeggio-feel repeats - galloping subs - ratcheted low-end motifs - pseudo-sequenced melodic subdivisions
If Bohm is pitch-tracked, Groove’s repetitions inherit a harmonically related pitch context.
These are not “pitched melody” in the classic sense, but they are useful for melodic support layers: - resonant rumble tails - tuned sub under a note - noisy top texture following a bass phrase - sustained drone synced to melodic events
The manual notes:
- GRV ENV system option can be:
- FALL
- SUSTAIN
With SUSTAIN, Groove can hold after the 4th tap level, which is excellent for:
- bass drones
- sustained harmonic beds
- one-note underpinning below a melody
- transitions and breakdowns
Also: - Perf Vol option can be set so Performer VOL controls only BOHM - the manual says this allows Groove to drone without hearing the Bohm kick
That is extremely useful melodically: - Bohm can act as the triggering/pitched event source - Groove can become the sustained note layer
Groove effect variations: - LP - HP - BP - DIST
This means Groove can function as: - a filtered bass shadow - a band-passed tonal repeat layer - a high-passed melodic top - a distorted harmonic duplicate
And STEREO width can widen the melodic layer spatially.
Performer is not a voice generator by itself, but in a melodic patch it becomes the key to making Bohm/Groove feel like a complete musical instrument.
Performer has: - stereo IN - ducking based on HIT - effects - routing selector
So you can bring in: - another oscillator voice - a chord source - a sampler loop - a drone - a bassline from another module
Then combine it with Bohm/Groove.
The external input is ducked on every HIT. That means if you send in a drone, pad, or sustained oscillator: - Bohm can carve rhythmic space into it - creating a pulsing harmonic layer - synced to the melodic bass events
Performer variations make this more subtle and musical: - DUCK TIME = release time - DUCK SMTH = smoothing - DUCK BS = band split frequency
This is great for melody because you can: - duck only lows while preserving highs - create sidechained bass + sustained top - keep chord clarity while pulsing the low band
Performer CHN variation:
- ALL
- KICK
- INPUT
This allows several melodic configurations:
Use if Bohm/Groove are your melodic voice and you want: - filter sweeps on the bassline - beat roll on the bass - live stutter transitions
Use if Bohm is your rhythmic melodic anchor and incoming audio is a pad/lead/drone.
Process the full combined musical texture.
Available variations: - DJ FILTER - HP - LP - BEAT ROLL - SLIP ROLL
These are excellent for melodic performance:
Perfect for: - opening/closing basslines - breakdown filtering - morphing a bass phrase into a thin lead-like line - isolating highs from an incoming melodic texture
Useful for: - carving low-end vs top-end - creating arrangement movement - making one melodic layer sit behind another
These can turn sustained or repeating melodic material into: - glitch fills - stutters - rhythmic note slicing - end-of-phrase transitions
Patch - Sequencer pitch CV -> PITCH CV - Sequencer gate -> HIT - Audio from OUT
Set - PITCH knob full CCW - PITCH attenuverter full CW - system Pitch CV to correct range - LENGTH fairly long - SUSTAIN up - moderate ATTACK - reduced transient if too clicky
Result - monophonic bassline voice - especially strong with FM-2X, HZ-1, WT-4, XT-88
Patch - Same as above - Clock divider/multiplier or 16th clock -> Groove CLOCK
Set - Groove PITCH slightly above or below center - Groove LENGTH to taste - Use 2 / 3 / 4 to shape repeats - Groove COLOR toward repetition source - Groove FX with BP or DIST
Result - Bohm gives the root note - Groove gives related rhythmic melodic taps - feels like a bassline with ratchets or ghost notes
Patch - Melodic gate/pitch into Bohm - Regular clock into Groove - Use Performer if available
Set - Groove system GRV ENV = SUSTAIN - Groove level up - Bohm more transient-forward - If Performer present, set PERF VOL = BOHM so Groove can remain independent - Optionally duck external audio with Performer
Result - Bohm articulates notes - Groove forms sustained harmonic/sub layer - excellent for techno hypnosis and dark ambient low-end melody
Patch - Bohm sequenced melodically - External stereo or mono voice into Performer IN - Optionally send a chord or drone source
Set
- DUCK to taste
- DUCK BS so low band ducks more than highs
- CHN = INPUT or ALL
- Use DJ FILTER or LP
- toggle FX synced to HIT for phrase changes
Result - Bohm acts as rhythmic/melodic bass anchor - incoming voice becomes breathing accompaniment - very effective for live melodic techno
Because snapshots save: - model variations - knob positions
you can prepare multiple melodic identities: - Step 1: clean FM sub bass - Step 2: brighter distorted chorus bass - Step 3: long drone breakdown - Step 4: filtered/stuttered fill
Then use: - Song mode for fixed arrangement - Jam mode for improvisational cueing
This is one of the strongest non-obvious melodic uses in the manual: Bohm becomes a preset-morphing low-end instrument rather than just a kick generator.
These matter a lot.
Set to:
- 0..1V
- 1..2V
- 2..3V
depending on your sequencer’s voltage span.
The SUSTAIN attenuverter can instead control VELOCITY CV. This can be useful if you want more expressive sequencing of note dynamics rather than sustain amount.
FALL for rhythmic behaviorSUSTAIN for drones and held layersCan output: - Groove envelope - inverted Bohm envelope - Performer envelope - Bohm envelope
This is very useful for melodic patches because you can use the output to animate other modules: - open a filter on another oscillator - duck a bass drone - modulate VCA on a melodic layer - create envelope-following accompaniment
You can hard-pan: - Bohm - Groove - Performer input
This is surprisingly useful for melodic patching: - route Bohm to left and Groove to right - process them separately downstream - build mono dual-line structures from the stereo output
Useful for tuning Bohm/Groove into a more musical role in a mix: - tame club boom - emphasize note definition - shape bassline presence
It won’t replace a full-range oscillator voice, but within its designed range it can produce very strong, mix-ready melodic low-end.
Because Groove repetitions are retriggered taps, not delay echoes, they can sound tighter and more intentional than a traditional delay.
Different Bohm models and snapshots can behave like: - verse bass - chorus bass - breakdown drone - fill/stutter preset
With selective ducking and filter FX, Performer can make even static external melodic material feel locked to the kick/bass phrasing.
Load: - your own wavetable for pitch body - your own sample for attack/layer
That gives you a very personalized bass instrument.
The manual frames pitch around C1 to C2, so this is mainly: - bassline territory - low melodic hooks - tuned percussive phrasing
Each model interprets controls differently, so “melodic sweet spots” will vary significantly by model.
This is great for coherence, but less ideal if you want a completely separate second melody.
In Song mode, steps need enough time for preloading. Extremely rapid melodic preset switching may be constrained.
Used together, these modules are especially good for:
In practice, the strongest melodic identity of the system is:
Bohm = pitched low-end voice
Groove = related rhythmic/sub/drone companion
Performer = sidechain, filter, and transition processor for the whole musical layer
That combination makes the system much more than a kick module—it can function as a complete low-end melodic instrument with performance control.
Yes—these modules can absolutely be used to create melodic components.
Not as a conventional polysynth, but as a highly characterful low-register melodic system.
If you think of them as:
then together they become a powerful tool for bass melodies, rhythmic melodic motifs, drones, and live-evolving low-end arrangements.