Quick Guide
Q BIT
Bit Crusher with Time Hold
Q BIT is a bit crusher with a time hold. The crusher gives your sound its grit. HOLD grabs slices of your track and holds them, on your song’s tempo or at its own pace.
“I wanted to reshape the signal itself, giving it the character and musicality of a retro sound chip, while keeping it relevant to modern production. That idea became Q BIT: a way to make digital reduction playable.”Hisham Sidawi, Audio Equipment Designer
Pulsar Modular
MODEL
4Linear, SP-1200, M.93 and ZX Spectrum 128, each a character of its own.BITS
24 → 2Bit depth, from close to your track down to grit and noise.RATE
Host → 2 kHzThe sample rate of the crusher. Your session keeps its own.DIVISION
1/4 → 1/32Grabs on your tempo, straight, dotted or triplet; or 1 to 16 a second in Free.How it works
A crusher and a time hold
The crusher gives your sound its grit. HOLD grabs slices of your track and holds them, on your song’s tempo or at its own pace. MIX blends the result with your dry track, and OUTPUT sets the final level.
INPUT
The level into Q BIT, −24 to +24 dB.
▸
HOLD Off · Free · Sync
Grabs slices of your track and holds them: on DIVISION in Sync, at HOLD RATE in Free.
Crusher MODEL
Linear (BITS, RATE), SP-1200, M.93 (MULTIPLY) or ZX Spectrum 128 (CHANNELS).
▸
MIX
The crushed sound (W) against your dry track (D).
▸
OUTPUT
The final level, −24 to +24 dB, after MIX.
DYour dry track goes around HOLD and the crusher to MIX: 100% D is all dry.
HOLD Off
No hold: the crusher still works on its own.One model at a time
Each MODEL shows only its own boxes: BITS and RATE for Linear, MULTIPLY for the M.93, CHANNELS for the ZX Spectrum 128.No clicks
Every control on the panel can be automated, and no change clicks, even while the music plays. Q BIT tells your DAW its latency, and the DAW keeps everything in time.Get started
Six steps to the first pulse
1
Insert it
Insert Q BIT on a drum loop, a synth or any other track, mono or stereo.
2
Start clean
Leave HOLD Off for now. Under MODEL, keep Linear.
3
Crush
Lower BITS to 8 or 4 bit for stronger crushing. Lower RATE to 8 kHz for a more pronounced digital sound.
4
Hold on the grid
Set HOLD to Sync and DIVISION to 1/16. Each sixteenth note now starts a slice of your track and holds it until the next one.
5
Shape the rhythm
Turn SEGMENT up and down. Higher keeps more of each slice; lower makes the hold, and the rhythm, stronger.
6
Blend and level
Blend your dry track back in with MIX, then match the level with OUTPUT.
TipThe help strip under the panel describes the control under your mouse. It starts off: click the strip, or choose Tooltip in the menu, to turn it on for every Q BIT window.
The help strip, on, with the mouse over SEGMENT.
Interactive panel
Hover or tap any control
20 hotspots. Hover for a summary, click to pin the full description; click again or tap outside to release.
Q BIT after the six steps: Linear at 4 bit and 8 kHz, HOLD Sync at 1/16, SEGMENT just inside the green arc. The dot beside the preset name says a control moved since the last load.
The time hold
HOLD, the heart of Q BIT
At every grab, a slice of your track plays as it is; then the hold freezes its end and sustains it until the next grab. On a held note it sounds like a tremolo or a pulse; on drums, like a rhythm of short hits and held tones.
A drawing of the idea, not a measurement: four grabs on a track with a hit on every grab and one off the grid. Move SEGMENT to see which part of each slice plays as it is and which part is held.
| Control | Range | What it does |
|---|---|---|
| HOLD | Off · Free · Sync | Off: no hold, the crusher still works. Free: grabs at HOLD RATE. Sync: grabs on your DAW’s tempo, at DIVISION. |
| DIVISION | 1/4 to 1/32 | Sync only. The note value of the grabs, straight, dotted (.) or triplet (T). There is no dotted 1/32. |
| HOLD RATE | 1 to 16 Hz | Free only. How many grabs a second: slow rates hold long and smooth; fast ones stutter. |
| SEGMENT | 10 to 90 % | How much of each slice plays before the hold takes over. Raise it to keep more of the performance; lower it for a stronger rhythm. |
HOLD
DIVISION and HOLD RATE are dimmed when their mode is not in use. All three are dimmed while HOLD is Off.
Sync: DIVISION sets the grabs; HOLD RATE is dimmed, and the green arc shows on SEGMENT.
Sync and your loop
In Sync the grabs sit on your song’s grid, not on the hits. For a loop that sounds the same on every pass, use whole bars; with a dotted DIVISION, three bars or a multiple of three. When the transport stops, Q BIT keeps grabbing at the last tempo.
The green arc
In Sync, a green arc on the SEGMENT ring shows the settings that keep every hit of the last bars intact. Set SEGMENT just inside the arc for the strongest rhythm that loses no hits.
The arc appears after a few clear hits and stays still while the groove is steady. A new DIVISION or tempo clears it until new hits come in. There is no arc in Free, and none on sounds without clear hits, such as a pad.
TipHits sound cut off or missing in Sync? Raise SEGMENT, follow the green arc, or try another DIVISION.
The sound
MODEL: four characters
MODEL picks the character of the crusher. Each model shows only its own boxes.
| Model | Character | Its boxes |
|---|---|---|
| Linear | Flexible bit crushing: you set the bit depth and the sample rate. | BITS, RATE |
| SP-1200 | A punchy, gritty drum-sampler character with a softer top end. | none |
| M.93 | A vintage digital-delay character: clean on quiet sounds, gritty on loud ones. | MULTIPLY |
| ZX Spectrum 128 | A coarse, retro home-computer character. Mono, like the original, or a chip for each side. | CHANNELS |
MODEL
Linear: BITS and RATE.
BITS
The bit depth, from 24 down to 2 bit. Fewer bits give more grit and noise. Q BIT starts at 16 bit, close to your track.
RATE
The sample rate of the crusher, from Host (your session rate) down to 2 kHz. Lower rates turn the highs into the grit of an old sampler. Your session keeps its own rate.
MULTIPLY
M.93 only: 1x, 2x, 4x or 8x. Each step makes the sound darker and grainier.
CHANNELS
ZX Spectrum 128 only: Mono or Stereo. Mono is the machine as it was built: both sides play the same. Stereo gives each side a chip of its own; the two never quite agree, so a held sound moves across the field and drums crackle at the sides.
Steps you can see
BITS
RATE
Fewer BITS make taller steps, with more grit and noise; a lower RATE makes longer steps and turns the highs into grit. The display on the panel draws the same kind of picture: the faint line is the sound going in, the bright stepped line the sound coming out.
An illustration on a plain sine, drawn by this page, not by Q BIT.
TipThe M.93 is hardest on hats and cymbals. Give it a little less INPUT than the other models.
NoteOn the ZX Spectrum 128, INPUT sets how much of the chip’s range you use. Up traces the tone more closely; down keeps the punch, with grittier tails. Very quiet input can crackle or fall silent: raise INPUT until the sound comes through, then set the level with OUTPUT.
Levels and the display
Drive, blend, level, compare
| Control | Range | What it does |
|---|---|---|
| INPUT | −24 to +24 dB | The level into Q BIT. More drives the crusher harder; too much clips. |
| MIX | 0% D to 100% D | Blends the crushed sound (W) with your dry track (D). The readout shows the dry part: 0% D is all crushed, 100% D is all dry. |
| OUTPUT | −24 to +24 dB | The final level, after MIX. |
| BYPASS | Off · On | Switches Q BIT out. The button glows pink while bypassed. Your DAW’s bypass does the same. |
SHIFT links INPUT and OUTPUT
Hold SHIFT while you turn INPUT or OUTPUT, and the other one moves the opposite way: you change the drive and keep the level.
W · D
W is the crushed sound, D your dry track. The readout under MIX shows the dry part, so 0% D is all crushed and 100% D is all dry.
The display
The display shows your sound as it plays: the faint line is the sound going in, the bright stepped line the sound coming out. Fewer bits make the steps easier to see. At the right, OUT and IN show the peak levels in dBFS, one above the other, so you can compare them at a glance.
TipSet the crush by ear with INPUT and BITS, then match OUT to IN with OUTPUT to compare fairly with BYPASS.
Starting points
Six places to start
Settings from the User Guide, each with the factory preset that holds it. Take it from there by ear.
Parallel crunch
Drums › Parallel Crunch
SetLinear, 4 bit, then MIX toward D.
You hearYour track with the crushed sound blended under it.
Classic digital
Drums › That 8-Bit Kit
SetLinear, BITS 8 bit, RATE 8 kHz, HOLD Off.
You hearA pronounced digital sound, the highs turned into the grit of an old sampler.
Sixteenth pulse
Rhythm › Sixteenth Pulse
SetHOLD Sync, DIVISION 1/16, SEGMENT just inside the green arc.
You hearThe strongest rhythm that loses no hits.
Triplets over straight drums
Rhythm › Triplet Swing
SetDIVISION 1/8T with SEGMENT around 75 %.
You hearGrabs on a triplet grid over straight hits; the high SEGMENT keeps the hits.
Free stutter
Rhythm › Free Stutter
SetHOLD Free, HOLD RATE 12 to 16 Hz, SEGMENT low.
You hearFast grabs stutter at their own pace, off the grid.
Dark old delay
Lo-Fi Machines › Old Delay Dark
SetM.93 with MULTIPLY at 4x or 8x.
You hearEach MULTIPLY step makes the sound darker and grainier.
In your DAW
Formats, folders and the session
Q BIT is a VST3, AU and AAX plug-in for macOS and Windows, and a VST3 and LV2 plug-in for Linux. It installs to these folders:
| Format | System | Folder |
|---|---|---|
| VST3 | macOS | /Library/Audio/Plug-Ins/VST3/Pulsar Modular/ |
| VST3 | Windows | C:\Program Files\Common Files\VST3\Pulsar Modular\ |
| AU | macOS | /Library/Audio/Plug-Ins/Components/ |
| AAX | macOS | /Library/Application Support/Avid/Audio/Plug-Ins/Pulsar Modular/ |
| AAX | Windows | C:\Program Files\Common Files\Avid\Audio\Plug-Ins\Pulsar Modular\ |
| VST3 | Linux | ~/.vst3/ |
| LV2 | Linux | /usr/lib/lv2/ (package) or ~/.lv2/ (archive) |
To remove it on macOS or Windows, delete the Q BIT files (.vst3, .component, .aaxplugin) from these folders; on Linux, see Linux.
Mono, stereo, in time
Q BIT runs on mono and stereo tracks. It tells your DAW its latency, and the DAW keeps everything in time.
The session
Your session saves every control and the window size. Every control on the panel can be automated, and no change clicks, even while the music plays.
The window
Drag the corner of the window to resize it. Set Default Size in the menu makes the current width the size every new window opens at.
A fresh insert
A fresh insert starts clean: HOLD Off, MODEL Linear, 16 bit at your session rate, MIX all crushed, INPUT and OUTPUT at 0 dB. To start from a sound of your own instead, make it the startup default (Presets).
Presets and A/B
The preset strip and the browser
The strip above the panel holds your presets. The name in the middle is the preset you loaded; the arrows step through the presets of the bank, and a dot beside the name means a control moved since the last load or save. Click the name to open the browser: folders on the left, presets on the right, a search box, and a star on each preset for your favorites. Click a preset to load it, double-click to load it and close. SAVE overwrites the preset you loaded; SAVE AS names a new one. Right-click a preset for the rest.
Preset browser: point at any element
★ Favorites (2)
⌕ Search (type above)
All / root
Drums
Extreme
Lo-Fi Machines
Rhythm
Synths and Keys
Vocals and Samples
☆Chip Pulse
☆Dotted Shuffle
☆Eighth Note Chop
★Free Stutter
☆Half Time Freeze
☆Pulse Under the Beat
☆Sixteenth Pulse
☆Slow Tremolo Hold
★Triplet Swing
Right-click on a preset
Sixteenth Pulse
Load preset
Save here...
Rename...
Edit description and tags...
Tags
Delete
Save these settings as the startup default
Reveal in Finder
Every sixteenth grabs a slice of your loop and holds it: a pulse locked to the grid. Set SEGMENT just inside the green arc so no hit goes missing.
A / B · COPY
A and B are two complete settings to compare. Click a letter to switch; the lit one is what you hear. COPY makes the other letter match what you hear now, so you can tweak from there and flip back to compare. They are for the moment: your session saves the settings you hear, not both.
The startup default
Right-click a preset and choose Save these settings as the startup default: the sound you hear becomes the one every new Q BIT opens with.
NotePresets are files on your disk. Open Preset Folder in the menu shows the bank, so you can back it up or carry it to another computer.
Factory presets
Q BIT comes with 33 presets in six folders. Each note below is the description the browser shows; the tags are the ones the search finds.
| Preset | Description and tags |
|---|---|
| Drums | |
| That 8-Bit Kit | The classic 8-bit sound on a drum loop: grainy hats, a kick with a cardboard edge. Drop it on a full loop or a breakbeat. |
| Dusty Breaks | The punchy, dark drum-sampler sound on a breakbeat or a sampled loop. INPUT is up a little so the hits dig in; OUTPUT brings the level back. |
| Parallel Crunch | Your drums as they are with a crushed copy under them: the dry keeps the punch, the crush adds grit. Move MIX toward W for more of it. |
| Top End Grit | A rough top end for hats, shakers and tambourines without losing the hit: a moderate crush with a good part of the dry track kept. |
| Rhythm | |
| Sixteenth Pulse | Every sixteenth grabs a slice of your loop and holds it: a pulse locked to the grid. Set SEGMENT just inside the green arc so no hit goes missing. |
| Chip Pulse | The home-computer chip on a sixteenth pulse: every grab holds a buzzing tone until the next one. INPUT is up because the chip needs level; set SEGMENT just inside the green arc. |
| Eighth Note Chop | Slower grabs, longer holds: each eighth note freezes its tail into a tone. Works on drums and chords alike. The green arc on SEGMENT shows the safe setting. |
| Triplet Swing | Triplet grabs over straight drums put a swing on a loop that has none. SEGMENT stays high so the hits survive; the green arc shows where they do. |
| Dotted Shuffle | Dotted sixteenths pull the grabs off the grid for a three-against-four feel. Trim your loop to three bars so every pass matches; the green arc keeps the hits. |
| Half Time Freeze | Quarter-note grabs hold most of each beat: a chord or a pad turns into a gated pulse on the beat. On drums, set SEGMENT inside the green arc. |
| Pulse Under the Beat | The dry loop on top, a crushed sixteenth pulse underneath: the groove stays, the pulse adds motion. The green arc on SEGMENT shows the safe setting. |
| Free Stutter | A fast stutter at its own pace, off the grid, with SEGMENT low for the strongest effect. Automate HOLD to switch it in for a fill. |
| Slow Tremolo Hold | Four grabs a second on a held note or a pad: a tremolo that freezes between pulses, without touching the pitch. |
| Synths and Keys | |
| Chiptune Lead | A lead or an arp as a game console would play it: thin, bright and buzzing. Single-note lines take it best. |
| Lo-Fi Keys | Electric piano or a soft synth with the shine taken off: a little hiss, a little dullness, like a cassette of a demo. |
| Pad Grain | A pad with grain in it: the crush at your session rate keeps the top end but puts a texture on the sustain, with part of the dry track on top. |
| Wide Chip Pad | A pad or a held chord through two home-computer chips, one a side: the two differ, so the sound spreads and moves. INPUT is up because the chip needs level. |
| Bass Crunch | A bass line with a crushed copy on top of it at your session rate: the low end stays clean in the dry part, the grit sits in the mids. |
| Vocals and Samples | |
| Phone Vocal | A vocal through a small speaker and a bad line: the top end gone, grain in its place. For a verse, an intro or a shouted sample. |
| Grit Under the Vocal | Mostly your vocal, with a crushed copy under it for edge and presence. The dry part keeps the words clear. |
| Sampler Chop | A sample through the drum-sampler sound, chopped on eighth notes the way a pad player would retrigger it. SEGMENT is high to keep the attacks; the green arc shows the safe setting. |
| Old Sample Pack | A loop or a one-shot with the shine of a modern sample pack taken off: a little dull, a little grainy, the loud parts rougher than the quiet ones. |
| Spoken Word Stutter | A spoken line stuttered eight times a second: the words become a rhythm of their own. Automate HOLD on and off for one phrase at a time. |
| Lo-Fi Machines | |
| Drum Sampler | The drum sampler as it is, no extra drive: punchy, a softer top end, the classic hip hop crunch. Push INPUT for more. |
| Old Delay Clean | The vintage digital delay at its full rate: clean on quiet passages, gritty when it gets loud. INPUT is a little down, as it is hardest on hats and cymbals. |
| Old Delay Dark | The vintage digital delay at its longest setting: dark, grainy and dull, like a return from another age. Try it on a synth, a Rhodes or a vocal throw. |
| Home Computer | The home-computer chip played as a sampler: raw, buzzy and mono, with INPUT up so it traces the tone and OUTPUT bringing the level back. |
| Home Computer Hard | The same chip with INPUT at 0: the hits keep their punch and the tails get grittier. Raise INPUT if a quiet track falls silent. |
| Extreme | |
| Two Bit Noise | Two bits and a low rate: the sound is barely there, the noise is. A breakdown effect, or automate MIX to crush in and out. |
| Bottom of the Well | The rate so low that only the bass and a smear of the mids survive. Pull MIX toward D for a drop that opens back up. |
| Buzzsaw Chip | The home-computer chip pushed hard and in stereo: a buzz with the tune still in it, crackle at the sides. For a riser or a breakdown. |
| Glitch Grid | Low bits, a low rate and triplet sixteenth grabs with SEGMENT low: a glitching machine locked to the tempo. For a fill, a riser or a bar of chaos. |
| Robot Voice | Sixteen grabs a second with the shortest SEGMENT, on a crushed vocal: a buzzing robot that keeps the words. Ride MIX to bring the human back. |
Mouse and keys
What a click does
| Do this | What happens |
|---|---|
| SHIFT + turn INPUT or OUTPUT | The other one moves the opposite way: you change the drive and keep the level. |
| Click the help strip | Turns the help on or off for every Q BIT window. |
| Click the preset name | Opens the browser. |
| Click ◀ or ▶ beside the name | Steps through the presets of the bank. |
| Click a preset · double-click it | Loads it · loads it and closes the browser. |
| Right-click a preset | Rename, description and tags, delete, and Save these settings as the startup default. |
| Click A or B · COPY | Switches between the two settings · makes the other letter match what you hear. |
| Drag the corner of the window | Resizes the window. |
| Click the line across the top of the panel | Opens the license window, when the line says Q BIT needs the server. |
License
Free, with a license key
Q BIT is free, but like every Pulsar Modular plug-in it needs a license: you get the key from pulsarmodular.com. Until Q BIT is activated, it plays a soft noise instead of your audio and the license window opens by itself; License Status in the menu opens it any time.
- Paste your license key.
- Click Activate.
The status line turns green and your audio returns at once, with no restart.
| Button | What it does |
|---|---|
| Activate | Activates this computer with the key. |
| Deactivate | Frees this computer’s seat, even offline; the server hears at the next contact. |
| Refresh | Checks the license now. |
| Account | Opens your account page on the web, where you manage your computers. |
The license renews online by itself. Q BIT keeps playing offline for a while; when it needs the server, a line across the top of the panel says so: click it for the license window.
NoteIf you are leaving the computer for good, deactivate the license first.
Linux
VST3 and LV2 on Linux
Q BIT runs on 64-bit Intel and AMD Linux as VST3 and LV2, with glibc 2.34 or newer: Ubuntu 22.04, Debian 12, Fedora 35 or later, Arch and others. Check with getconf GNU_LIBC_VERSION in a terminal. Install one form, not both:
Package (.deb)
For every user on the computer. In a terminal opened in the download folder:
sudo apt install ./q-bit_*_amd64.deb
For an account added later, run once:
sudo dpkg-reconfigure q-bit
Archive (.tar.gz)
For your account only, with no admin rights. Unpack it, then in the unpacked folder:
./install.sh
Then rescan the plug-ins in your DAW, or restart Ardour or Mixbus.
| DAW or track | Use |
|---|---|
| REAPER | The VST3: REAPER cannot automate the LV2. |
| Bitwig Studio | The VST3. |
| Ardour, Mixbus | Restart Ardour or Mixbus after installing. |
| A mono track | The VST3: the LV2 is stereo only. |
Updates and removal
An update never overwrites a preset. To remove Q BIT, run sudo apt remove q-bit, or ./uninstall.sh in the archive folder; both keep your presets.
NoteBefore you reinstall Linux, deactivate the license (License): Q BIT may count the new installation as a new computer.
At a glance
Formats, systems and tracks
| Formats | macOS: VST3, AU, AAX. Windows: VST3, AAX. Linux: VST3, LV2. |
| Linux | 64-bit Intel and AMD, glibc 2.34 or newer: Ubuntu 22.04, Debian 12, Fedora 35 or later, Arch and others. |
| Tracks | Mono and stereo. The LV2 is stereo only: on a mono track, use the VST3. |
| Models | Linear, SP-1200, M.93, ZX Spectrum 128. |
| Latency | Q BIT tells your DAW its latency, and the DAW keeps everything in time. |
| Automation | Every control on the panel; no change clicks, even while the music plays. |
| Window | Resizable from its corner. Your session saves the size; Set Default Size sets it for every new window. |
| License | Free, with a license key from pulsarmodular.com. |
Troubleshooting
If something seems wrong
Sound and HOLD
I hear a soft noise instead of my audio.
Q BIT is not activated on this computer. Activate it (License).
HOLD does nothing.
HOLD is Off. Set it to Sync or Free.
Hits sound cut off or missing in Sync.
Raise SEGMENT, follow the green arc, or try another DIVISION.
Every pass of my loop sounds different.
Trim the loop to whole bars; with a dotted DIVISION, to three bars or a multiple of three.
I cannot find BITS, RATE, MULTIPLY or CHANNELS.
BITS and RATE belong to Linear, MULTIPLY to the M.93, CHANNELS to the ZX Spectrum 128. Each model shows only its own boxes.
The ZX Spectrum 128 is silent or crackles.
Raise INPUT.
The sound is mono.
The ZX Spectrum 128 starts in Mono, like the original. Set its CHANNELS to Stereo.
The panel and your DAW
The help strip says HELP OFF.
Click the strip, or choose Tooltip in the menu. The switch is shared by every Q BIT window.
My DAW lists a parameter called Dump Info.
Q BIT flips it when a setting that is not a knob changes, so your DAW saves the change with the session. Leave it alone and do not automate it.
Linux
Q BIT does not appear in my DAW.
Rescan plug-ins or restart the DAW, and check that the system has glibc 2.34 or newer.
Ardour or Mixbus crashes while scanning plug-ins.
Q BIT may be installed twice, from the package and from the archive. Remove one of them.
I cannot automate Q BIT in REAPER.
Use the VST3.
Crackles at small buffer sizes.
Give your user real-time audio rights (your distribution’s audio setup guide shows how), then log in again. On a laptop, also set the power profile to Performance.