Load the instrument
Create an instrument/MIDI track in a VST3-compatible DAW and insert SUBTERRAIN. The Init preset opens as a neutral classic kick at 130 BPM.
Official user guide · Version 1.0.2
Shape the impact.
Build the room.
SUBTERRAIN combines a layered kick synthesizer, rhythm engine and purpose-built spatial chain in one macOS VST3 instrument. This guide explains every visible control, the complete signal path, practical recipes, installation, trial and registration.
First sound in five steps
Quick start
Trigger it
Press play for the internal 16-step pattern, or send MIDI note-on events from the host. Incoming MIDI velocity scales each trigger.
Build the kick
Start with Kick Generator Tune, Decay, Drop and Pitch Time. Add Wave or OSC in the Mixer only when the core is stable.
Create the tail
Raise Rumble Amount, darken Tone, then add Ambience or Long-tail Reverb. Keep the dry transient audible for contrast.
Finish safely
Use Final Filter for overall tone, MASTER for normal output level and Gain FX for compressed, saturated loudness without hard digital clipping.
End-to-end architecture
Signal flow
Sequencer / MIDI→Kick + Wave + OSC + Sub→Mixer→Kick Shape→Compressor→Rumble→Delay→Ambience→Long-tail→Final Filter→Gain FX→Extended Mix→Master
Source domain
Kick Generator, Wave Layer, OSC Layer and the optional Sub Generator form four source voices. The Sub Generator can follow its own synchronized 16-step pattern.
Kick-only domain
Mixer, Kick Shape and Compressor define the direct impact before time-based effects. This is where punch and tonal focus are best established.
Spatial domain
Rumble, Delay, Ambience and Long-tail Reverb extend the sound in time. The complete result then reaches Final Filter, Gain FX and MASTER.
Rhythm and triggering
16-step velocity sequencer
ControlRange / choicesFunction and use
Steps 1–16Off · Half · Full
Each click cycles through three states. Off is silent; Half uses the global Half Step Velocity; Full always triggers at full internal velocity. Color and label show the state.
Half Step Velocity0–100%
Sets only the level of Half steps. Full steps remain unchanged. At 0%, Half is genuinely silent—useful for automation and evolving patterns.
Rate15–300 BPM
Controls manual tempo. Four sequencer steps make one quarter note, so a conventional four-on-the-floor pattern uses steps 1, 5, 9 and 13.
SyncOn · Off
With Sync On, the host supplies BPM and the display mirrors it. With Sync Off, Rate becomes the active clock. The Source display is informational, not a button.
MIDI note-onHost velocity
Every incoming note-on triggers a fresh kick event and uses the MIDI velocity. This allows SUBTERRAIN to follow the DAW piano roll instead of the internal pattern.
Four on the floor
FULL · off · off · offRepeat across all 16 steps. Lower Half Step Velocity is irrelevant until Half steps are introduced.
Ghost push
FULL · off · HALF · offPlace quiet Half triggers before or after the main beats. Start around 20–35% to create motion without competing with the downbeat.
Host performance
Disable or clear internal steps and sequence notes in the DAW when you need arrangement-level variations, groove templates or per-note velocity.
Four coordinated voices
Kick sources & mixer
Kick Generator
THE HEART OF SUBTERRAIN
100% synthesized. Zero sample playback.
The Kick Generator creates its entire sound in real time from a phase-coherent oscillator body, an exponential pitch sweep, a synthesized transient burst, harmonic shaping and dedicated punch, weight, tightness and drive stages. It does not read or replay a kick recording. This means Tune and pitch contour are structural parts of the voice rather than pitch-shifted sample playback, and every trigger is generated at the host sample rate with a repeatable phase and envelope.
Build the identity of the kick here first. The optional Wave Layer is the only sample-based source; the OSC Layer is a second synthesized voice. Both are additions to the Kick Generator, not replacements for it.
ControlRangeFunction and use
Tune30–80 Hz
Sets the settled fundamental. Tune by ear against the bass; lower values feel deeper, higher values cut through smaller speakers.
Decay0.08–1.2 s
Length of the synthesized kick body. Short values make tight drums; longer values produce sustained low-end that needs more mix space.
Drop0–220 Hz
Amount of initial pitch above Tune. More Drop increases the classic downward kick sweep and perceived impact.
Pitch Time3–120 ms
Duration of the pitch sweep. Very short values click; longer values create a rounded “pew” or tom-like descent.
Click0–100%
Transient level at the very front of the kick. Use it to improve audibility without raising the entire body.
Drive0–100%
Adds harmonics and density inside the kick voice. Useful for making low fundamentals translate on compact playback systems.
Punch0–100%
Emphasizes the early body after the click. Combine moderate Punch with a slower compressor attack to keep the transient forward.
Weight0–100%
Adds a phase-locked low body inspired by classic analogue drum machines, without the unrelated vibrato of a separate sub oscillator.
Click Tone0–100%
Moves the transient character from dark/soft toward brighter/harder. Reduce it when the kick conflicts with hats.
Tight0–100%
Focuses the envelope and low-frequency body for a shorter, firmer result. Counterbalance with Decay when needed.
Wave Layer Source
An embedded sample-based layer with 24 selectable sounds. It contains three normalized analogue source families and carefully shaped variations, including Classic, Classic 2, Classic 3, Deep Body, Punch, Tape Slam, Dark Boom, Soft Arc, Impact Coil, Body Bloom and Submerged Arc. All audio is compiled into the plug-in; no external sample file is required.
- Pitch: −24 to +24 semitones.
- Attack: 0–100 ms source-local fade-in.
- Decay: 0.03–1.5 s contour; Dark Boom extends the effective tail.
- Delay: prepends 0–500 ms of silence to every new Wave voice.
OSC Layer Source
A synthesized reinforcement layer with Sine, Square, Saw, Triangle and Noise. Sine is cleanest for sub reinforcement; Saw and Square add harmonics; Noise can become a transient or industrial texture.
- Pitch: controls oscillator frequency relative to the engine.
- Attack: 0–100 ms; also opens a transient low-pass so sharp waves soften gradually.
- Decay: 5 ms–1.2 s.
- Delay: prepends 0–500 ms of silence before each oscillator voice.
Mixer
The vertical Mixer knobs independently balance Kick, Wave and OSC. The Sub Generator has its own larger Mix control on its dedicated page. Start with Kick at 100% and the other sources at 0%; then introduce one layer at a time.
Sub Generator
The Sub Generator is an additional fully synthesized low-frequency kick voice. It recreates the rounded behavior of classic analogue bass drums without sample playback and can be pushed far beyond the main Kick Generator.
GroupControlsFunction and use
Pitch contourPitch · Drop · Sweep
Sets the final low pitch, initial pitch excursion and the speed/shape of its descent.
TransientAttack · Transient · Soften
Moves from an immediate hard onset toward a rounded swell where only the low body remains.
BodyBody · Decay · Swell
Controls low-frequency weight, voice length and the later bloom of the synthesized body.
FinishTone · Drive · Comp
Shapes brightness, harmonic density and progressive compression before the Sub Mix.
Direct ADSRA · D · S · R
Shapes the pure Sub signal before tone, drive and compression. Its Init state is neutral.
Private sequencerOff / On · 16 steps
Off follows normal triggers. On disconnects the Sub voice from main triggers and uses its own 4×4 pattern while sharing host/manual BPM.
From shape to final output
Kick processing & effects
Kick Shape
A kick-only multimode filter placed after the source mix.
- Mode: Off, Low Pass, High Pass, Band Pass or Notch.
- Cut: 30–5000 Hz.
- Res: emphasizes the cutoff area.
Use Low Pass to remove click, High Pass for a thin layer, Band Pass for knock and Notch to carve a resonant conflict.
Compressor
An aggressive parallel compressor dedicated to the combined kick.
- Amount: bypass at 0%, then moves from density to radical limiting/saturation.
- ATK: 0.05–100 ms; slower settings preserve more initial transient.
- REL: 10–1000 ms; short release recovers quickly, long release holds the body down.
The vertical meter shows gain reduction rising from the bottom.
Rumble
Creates a ducked, low-passed feedback aftershock from each kick.
- Amount: rumble level.
- Decay: 0.4–8 s.
- Dark Tone: 50–500 Hz tonal focus.
- Drive: saturation and density.
For separation, lower Tone and increase Decay before raising Amount.
Delay
Feedback echo before both reverbs.
- Time: 1–1000 ms.
- Feedback: 0–95%.
- Dry/Wet: 0–100%.
Short times thicken; tempo-related times create repeats; high feedback should be balanced with the final filter.
Ambience Reverb
Short/medium early-reflection spaces: Small Room, Studio, Large Hall, Cathedral and Plate.
- Decay: room persistence.
- Damping: removes high-frequency energy over time.
- Dry/Wet: blend.
Use this for location and front-to-back depth before adding the long late tail.
Long-tail Reverb
A multi-second feedback-delay-network reverb with Chamber, Large Hall, Cathedral, Cavern and Endless spaces.
- Tail: 0.5–20 s.
- Damp: darkens the decay.
- Pre: 0–200 ms separation before the tail.
- Mix: long-tail blend.
Pre-delay preserves the kick transient; long decay plus strong damping creates the dark “room behind the kick.”
Tail Rhythm Shaper
Chops only the long reverb tail with an eight-step pattern.
- On/Off: bypasses the shaper.
- Rate: ¼ Speed, ½ Speed, 1× Step or 2× Step.
- Depth: modulation amount; 0% is neutral.
- Smooth: softens transitions.
- Steps 1–8: choose emphasized tail segments.
Final Filter
Processes the complete sound after all sources and time-based effects. Choose Low-pass, High-pass or Band-pass; Cutoff spans 20 Hz–18 kHz logarithmically and Resonance spans 0–100%.
Automate it for breakdowns because it affects impact and tail together.
Gain FX & MASTER
Gain FX spans −24 to +60 dB as a macro: below 0 dB it attenuates cleanly; above 0 dB it adds drive, adaptive compression and saturation, with distortion near the top. A soft ceiling prevents hard clipping at its output.
MASTER is the normal final level control. Use MASTER for balance; use Gain FX when you intentionally want a denser timbre.
See the complete result
Waveform & meters
Output waveform
Displays the end-to-end signal after the full chain. Orange highlights the initial impact; violet emphasizes the evolving tail. The time grid changes with the selected window.
MENU / 1 s / 4 s / 16 s
The time buttons select the visible capture span. MENU replaces the scope with the extended sound-design workspace; its label changes to WAVEFORM so you can return to the scope.
FREEZE / RETRIGGER
FREEZE holds the current trace for inspection. RETRIGGER arms a fresh capture and waits for the next kick onset, useful when comparing parameter changes.
The header L/R meter shows output activity against a dB scale. Watch it while adjusting MASTER and Gain FX, but use the DAW meter for final gain staging.
Extended workspace
Click MENU beside the waveform to replace the visualizer with the extended workspace. The three page buttons select Sub Generator, Extended Mix or Extended FX; click WAVEFORM to return. Changing pages only changes what is displayed—the current sound and enabled processors continue running.
Extended Mix
This page taps each source before the main effect chain and adds that clean copy back near the output, after Gain FX and the extended processors but before MASTER. It is a parallel-return mixer: it does not replace the normal source mixer and it does not reduce the effected path.
Kick Dry Return
Restores the synthesized Kick Generator impact after heavy reverb, filtering or saturation. Use it first when the transient has become indistinct.
Wave / OSC Dry Return
Returns the unprocessed Wave or OSC layer independently. This can recover sampled attack, harmonic bite or tonal reinforcement without making the entire wet chain louder.
Sub Dry Return
Restores the Sub Generator's direct, envelope-shaped voice. Its stronger upper range compensates for the naturally quieter low-frequency source.
Extended FX
Each module has its own power button and defaults to bypass, so opening this page does not alter the sound. The small displays visualize the current gate, fold or modulation shape. Build an effect one module at a time and compare it with its own On/Off button.
Rhythm Gate
A host/manual-tempo synchronized output gate. Choose 1/2, 1/4, 1/8 or 1/16; Depth moves from a flat signal toward deep chopping and Smooth rounds each edge to suppress clicks. It is especially effective on long rumble and reverb tails.
Rift Fold
Folds peaks back into the waveform for increasingly complex harmonics. Fold sets intensity and the number of folds; Mix blends the compensated processed signal with the clean path.
Void Mod
Applies cyclic output modulation. Rate moves from slower pulses toward faster metallic motion; Depth controls the excursion from subtle movement to radical reshaping.
Stereo Enhancer
Creates kick-derived side information while preserving the deepest bass in the centre. Width sets spread and Space controls a short 1.5–18 ms decorrelation delay. Always check mono compatibility.
Fattener
Derives a controlled octave-down companion from the combined kick layers instead of playing an unrelated sine. Tone limits its upper content and Amount blends the subharmonic reinforcement before the spatial chain.
Contour and movement
Amp envelope & LFOs
Final Amp Envelope
This global envelope shapes the mixed kick at the final amplitude stage; it is intentionally independent from Wave and OSC source contours.
ControlRange / choicesFunction and use
CurveEXP · LIN · LOG
Changes how each envelope segment travels. EXP feels natural and punchy, LIN is even, LOG moves rapidly before easing.
RetrigOn · Off
On restarts the envelope on every trigger. Off allows a new gate without forcibly restarting the current contour.
Attack0–250 ms
At 0 ms the original onset is unchanged. Raise it to soften the complete kick and any FX energy present at the onset.
Decay0–1000 ms
Controls the audible fall from peak to Sustain. Short settings create a fast, clicky contour; longer settings preserve more body.
Sustain0–100%
Level held after Decay while the gate remains active.
Release2–2000 ms
Controls the final fall after gate-off. Near-minimum values cut very quickly; maximum release approaches the unshaped natural continuation.
LFO 1 & LFO 2
Two independent low-frequency modulators can move one of the first four Kick Generator parameters: Tune, Decay, Pitch Drop or Pitch Decay. Deselect/bypass the LFO when no movement is wanted.
ControlRange / choicesFunction and use
ShapeSine · Square · Triangle · Sample & Hold
Sine is smooth, Square jumps between two values, Triangle moves linearly, and Sample & Hold produces stepped random movement.
Rate0.05–5 Hz
One cycle takes roughly 20 seconds at minimum and 0.2 seconds at maximum. Slow settings create evolving variation across several kicks.
Depth0–100% / target-scaled
Sets modulation strength. Start below 10% for pitch-related targets; larger values become an obvious sound-design effect.
TargetTune · Decay · Pitch Drop · Pitch Decay
Selects the Kick Generator parameter moved over time.
Phase0–360°
Offsets the LFO cycle. Use different phases on LFO 1 and 2 to avoid identical motion.
RetrigOn · Off
On restarts the LFO phase with each kick; Off lets it free-run across triggers.
Smooth0–100%
Rounds abrupt changes, especially useful with Square and Sample & Hold.
Slow analogue drift
LFO 1 → Tune, Sine, 0.05–0.15 Hz, very low Depth, Retrig Off.
Alternating punch
LFO 1 → Pitch Drop, Square, moderate Rate, low Depth; raise Smooth to remove hard steps.
Organic variation
LFO 1 → Decay and LFO 2 → Pitch Decay, both slow with different phases and shallow depths.
Recall and create sounds
Presets & state
The header chooser contains more than 50 protected factory presets. Arrow buttons move through the list. Loading a preset restores its complete parameter state, including all sequencers, source layers, extended pages, effects, envelope and modulation, so it does not inherit values from the previously loaded sound.
InitPrimal ScreamRift ScreamPanther StrikeFeral DepthRazor BedrockMotor VaultNocturnal MassStatic BurialRain CircuitSmoldering CoreServo ImpactCrushing ChamberVelvet DescentCreeping FaultMidnight FreightTwisted StrataPulse BreachSiren VaultPrismatic Depth
Save
Click SAVE, enter a name in the in-plugin overlay and confirm. A new user preset appears in the chooser. All persistent UI parameters are stored.
Delete
DELETE asks for confirmation. Only user presets can be removed. After deletion, the non-deletable Init preset is loaded.
DAW projects
VST3 state is stored with the host project. Parameter IDs are stable, so automation and session recall remain tied to the intended controls.
User presets are stored as .rum files in ~/Library/Application Support/QiOOPlugin/Subterrain/.
Practical starting points
Sound-design recipes
Tight club kick
Short, focused, loud
- Kick only; Wave and OSC at 0%.
- Tune 45–55 Hz, short Decay, high Drop, short Pitch Time.
- Moderate Punch and Tight; low Weight.
- Compressor Amount 25–45%, slower ATK, medium REL.
- Rumble and reverbs off; finish with modest Gain FX.
Dark warehouse rumble
Impact with a separate tail
- Keep the kick decay medium and transient clear.
- Rumble Amount 45–70%, Decay 3–6 s, Dark Tone 80–160 Hz.
- Add Long-tail Cathedral or Cavern, 6–12 s, high damping.
- Use Pre around 30–80 ms so the impact stays in front.
- Low-pass the complete chain if the room becomes metallic.
Industrial layered hit
Harmonics and movement
- Add Wave “Tape Slam” or “Hollow Concrete” at 15–35%.
- Add Saw or Noise OSC at a low mix with short decay.
- Use Kick Shape Band Pass or Notch for character.
- Drive Rumble moderately and add short Delay.
- Modulate Pitch Drop slowly with a smoothed LFO.
Rhythmic cathedral
Moving late reflections
- Select Cathedral or Endless Long-tail.
- Set Tail 10–18 s, substantial Damp and modest Mix.
- Enable Tail Rhythm Shaper at 1× Step.
- Choose a sparse 8-step pattern and raise Depth.
- Increase Smooth until the chopping breathes instead of clicking.
Current macOS installer
Installation, trial & registration
Install
Open the signed and Apple-notarized Subterrain-1.0.2.pkg and follow the installer. It installs the universal Apple Silicon + Intel VST3 for all users.
Scan
Restart the DAW. If SUBTERRAIN does not appear, trigger a VST3 rescan and confirm that the host supports 64-bit VST3 instruments.
Try
The unregistered plugin provides 30 minutes of accumulated use. Remaining time is shown in the registration overlay and persists across plugin and DAW restarts.
Register
Enter the exact licensed email address and its signed activation code in the in-plugin overlay. A valid license removes the trial limit and the About screen shows the licensed email.
VST3 locations
Release installer (all users)
/Library/Audio/Plug-Ins/VST3/Subterrain.vst3Typical user-only VST3 folder
~/Library/Audio/Plug-Ins/VST3/License file
~/Library/Application Support/QiOOPlugin/Subterrain.licensePersisted trial state
~/Library/Application Support/QiOOPlugin/.subterrain-trialUser presets
~/Library/Application Support/QiOOPlugin/Subterrain/Uninstall
Quit all DAWs, then remove /Library/Audio/Plug-Ins/VST3/Subterrain.vst3. Removing the plugin does not automatically erase the license, trial state or user presets from Application Support. Retaining those files preserves registration and sounds for a later reinstall.
For support, contact plugins@qioo.de. Include macOS version, DAW name/version, Mac architecture and a concise reproduction sequence.
Compatibility & operational notes
Reference
- Product
- SUBTERRAIN Rumble Kick
- Guide version
- 1.0.2
- Format
- 64-bit VST3 instrument
- Platform
- macOS 10.13 or later
- Architectures
- Apple Silicon (arm64) and Intel (x86_64)
- Input
- MIDI / VST3 note events and built-in 16-step sequencer
- Output
- Stereo
- Automation
- VST3 parameters are host-automatable; rapid continuous changes are smoothed in the audio engine where appropriate.
- Installer
- Developer ID signed, Apple notarized and stapled PKG
- Trial
- 30 minutes accumulated use, persisted locally
Guide for SUBTERRAIN 1.0.2 · Updated 6 September 2026 · © QiOO Publishing