# Engine catalogue

> 69 effect engines: 25 free and 44 paid. The 42 synths are under [Sounds](https://sournd.com/sounds/index.md). Every engine runs in JUCE through the sOURnd C ABI. Free engines download with no account: https://sournd.com/download/free/macos (macOS), https://sournd.com/download/free/linux (Linux) or https://sournd.com/download/free/windows (Windows).

Machine-readable: [https://sournd.com/catalog.json](https://sournd.com/catalog.json).

## Distortion

Clippers, saturation, fuzz and drive.

- [Brimm](/engines/brimm/index.md) (free, `org.sournd.distortion.brimm`): Clipper: shaves peaks at a ceiling you set, with a hard, soft or knee corner, oversampled for clean highs. Push the drive for loudness and bite, or keep it low to catch stray transients.
- [Calora](/engines/calora/index.md) (free, `org.sournd.distortion.calora`): Warm magnetic-style saturation: highs round off first, lows thicken, loud passages ease back gently.
- [Soft clip](/engines/soft-clip/index.md) (free, `org.sournd.distortion.soft-clip`): Level-compensated tanh saturation.
- [Grittance](/engines/grittance/index.md) (free, `org.sournd.distortion.grittance`): Lo-fi crusher: lower the sample rate and bit depth, fold the wave, and loosen the clock with jitter.
- [Asphalto](/engines/asphalto/index.md) (paid, `org.sournd.distortion.asphalto`): Lower-gain, darker bass fuzz: heavy body and a thick low-mid, with the top end grit mostly rolled away.
- [Kilnglow](/engines/kilnglow/index.md) (paid, `org.sournd.distortion.kilnglow`): Valve-style asymmetric drive rich in even harmonics; the bias sags with playing level for a touch-sensitive bloom.
- [Lithic](/engines/lithic/index.md) (paid, `org.sournd.distortion.lithic`): Plays amp and pedal captures and cabinet impulse responses you load: a neural capture, an IR, or both. Empty slots pass audio through clean.
- [Monstrous Mandarin](/engines/monstrous-mandarin/index.md) (paid, `org.sournd.distortion.monstrous-mandarin`): Thick valve-amp drive that saturates early and sits heavy in the low mids, with a dark-to-cutting tone sweep and a speaker-and-mic voice you can pull back to feed your own cab.
- [Patinor](/engines/patinor/index.md) (paid, `org.sournd.distortion.patinor`): Lo-fi character: makes anything sound played back from a worn record or tape, with drifting pitch, flutter, crackle and dust pops, hiss, a narrow bandwidth, gentle age saturation and optional bit and sample-rate crush. The surface noise rides under the playing and fades out with it.
- [Scary Satsuma](/engines/scary-satsuma/index.md) (paid, `org.sournd.distortion.scary-satsuma`): Tight, biting valve-amp drive that keeps getting heavier all the way up the gain, with a broad upper-mid push and a speaker-and-mic voice you can pull back to feed your own cab.
- [Thornet](/engines/thornet/index.md) (paid, `org.sournd.distortion.thornet`): Thick, saturated fuzz with an octave-up blend, a gate for tight stops and a scoop-to-bright tone stack.

## Dynamics

Compressors, limiters, gates and transient shapers.

- [Clampa](/engines/clampa/index.md) (free, `org.sournd.dynamics.clampa`): Punchy peak compressor: fast peak sensing with a firm knee, a punch control that lets transients through ahead of the gain reduction, and a parallel mix.
- [Attaq](/engines/attaq/index.md) (free, `org.sournd.dynamics.attaq`): Transient shaper: boost or soften the attack of each hit and lift or tuck its sustain, independent of level, with a speed control for tight or loose envelopes and a clip-safe output.
- [Ceilwall](/engines/ceilwall/index.md) (paid, `org.sournd.dynamics.ceilwall`): Transparent lookahead brickwall limiter: the gain ramps down before each peak arrives so the output never passes the ceiling, then recovers with a smooth release.
- [Hushel](/engines/hushel/index.md) (paid, `org.sournd.dynamics.hushel`): Dynamic EQ band: a bell that cuts only while its own band is louder than the threshold. Set it high and narrow-ish for de-essing; the wide control moves the cut from the band to the whole signal.
- [Sluice](/engines/sluice/index.md) (paid, `org.sournd.dynamics.sluice`): Gate and downward expander: opens above the threshold, closes below it minus the hysteresis after the hold time, and expands at the chosen ratio down to the range floor.
- [Unisill](/engines/unisill/index.md) (paid, `org.sournd.dynamics.unisill`): Glue compressor: RMS sensing that blends feed-forward and feedback detection, a soft knee and a release that speeds up on transient material and relaxes on sustained material.

## EQ

Parametric, graphic and character equalisers.

- [Lancetine](/engines/lancetine/index.md) (free, `org.sournd.eq.lancetine`): Surgical parametric EQ: 24 dB/oct low and high cuts (off at their extremes), low and high shelves and three fully parametric bells.
- [Fournel](/engines/fournel/index.md) (paid, `org.sournd.eq.fournel`): Passive-style program EQ: boost and attenuate the lows at the same frequency for a deep, tight bottom with a dip above it, a broad-to-sharp high boost, a separate high attenuation shelf, and a gentle output stage that thickens as it is driven.
- [Glazen](/engines/glazen/index.md) (paid, `org.sournd.eq.glazen`): Linear-phase parametric EQ: 24 dB/oct low and high cuts, low and high shelves and three bells with no phase shift between frequencies, so boosts and cuts keep transients and parallel paths aligned. Adds a fixed latency the host compensates.
- [Glintfoil](/engines/glintfoil/index.md) (paid, `org.sournd.eq.glintfoil`): Harmonic exciter: adds new overtones above a chosen frequency rather than boosting what is there. Harmonics sets the drive, colour leans the new overtones odd (bright, edgy) or even (sweet, open), and amount blends them in.
- [Gridelle](/engines/gridelle/index.md) (paid, `org.sournd.eq.gridelle`): Thirty-one-band third-octave graphic EQ, 20 Hz to 20 kHz, +-12 dB per band, constant-Q, for room and system voicing and precise tonal balance.

## Filter

Multimode, formant and stepped filters.

- [Veer](/engines/veer/index.md) (free, `org.sournd.filter.veer`): Resonant multimode filter that morphs continuously from low-pass through band-pass and high-pass to notch, with input drive and an envelope that sweeps the cutoff with the playing.
- [Kammerl](/engines/kammerl/index.md) (free, `org.sournd.filter.kammerl`): Tuned comb filter: rings any sound at a note or frequency, from a subtle metallic sheen to a singing, pitched resonance. Flip the polarity for a hollow tone an octave down; damping softens the ring.
- [Pivotta](/engines/pivotta/index.md) (free, `org.sournd.filter.pivotta`): One-knob performance filter: turn left and a low-pass sweeps down from the top to the deep bass, turn right and a high-pass sweeps up to thin the sound out; the centre is a clean bypass. Resonance adds a peak at the cutoff; Steep switches 12 to 24 dB/oct.
- [Glottan](/engines/glottan/index.md) (paid, `org.sournd.filter.glottan`): A vowel filter: three resonant peaks shaped like a voice, slid between two vowels by hand, by an LFO or by how hard the input plays, for talking, wah and growl tones.
- [Prowl](/engines/prowl/index.md) (paid, `org.sournd.filter.prowl`): Auto filter: a resonant low-pass, band-pass, high-pass or notch swept by an LFO (free or locked to the song, including sample-and-hold steps) and by how hard you play, with drive in front, grit after and a stereo offset.
- [Rung](/engines/rung/index.md) (paid, `org.sournd.filter.rung`): Warm resonant low-pass: four cascaded poles in a feedback loop with soft saturation, a slope control from 6 to 24 dB/oct and bass compensation for the level lost to resonance.
- [Treadle](/engines/treadle/index.md) (paid, `org.sournd.filter.treadle`): Pedal wah: one vocal, resonant peak rocked from heel to toe by the position control (map it to an expression pedal), or pushed by your playing for auto-wah. Hard notes squash the peak into a throaty honk.

## Modulation

Chorus, phaser, flanger, tremolo and friends.

- [Chorvane](/engines/chorvane/index.md) (free, `org.sournd.modulation.chorvane`): Lush three-voice ensemble chorus with stereo spread and a soft top end.
- [Eddyturn](/engines/eddyturn/index.md) (free, `org.sournd.modulation.eddyturn`): Eight-stage phaser with staggered notches, feedback for vocal sweeps and a stereo offset that turns it into a slow spin.
- [Tremola](/engines/tremola/index.md) (free, `org.sournd.modulation.tremola`): Tremolo that morphs from a smooth throb to a choppy pulse; widen the stereo phase for auto-pan.
- [Bellrung](/engines/bellrung/index.md) (paid, `org.sournd.modulation.bellrung`): Ring modulator: replaces each note with metallic sum and difference tones, from bell-like shimmer to harsh clangour, with an optional wobble on the carrier.
- [Ebb](/engines/ebb/index.md) (paid, `org.sournd.modulation.ebb`): Harmonic tremolo: lows and highs pulse in opposite phase, so the tone rocks between warm and bright with a subtle phasey sway instead of a plain volume throb.
- [Gyrecast](/engines/gyrecast/index.md) (paid, `org.sournd.modulation.gyrecast`): Rotating speaker: a spinning treble horn and bass drum, slow or fast, that speed up and slow down with real weight, heard by two microphones for a wide swirling stereo image.
- [Jetwake](/engines/jetwake/index.md) (paid, `org.sournd.modulation.jetwake`): Jet-sweep flanger with positive or negative feedback and a near through-zero mode that sweeps the echo across the dry signal.
- [Photocel](/engines/photocel/index.md) (paid, `org.sournd.modulation.photocel`): Lopsided, throbbing four-stage phase shifter swept by a lamp and light cell: chorus mode for liquid, pulsing notches, vibrato mode for a seasick pitch wobble.
- [Stairwhorl](/engines/stairwhorl/index.md) (paid, `org.sournd.modulation.stairwhorl`): Endless sweep: phaser or flanger notches that keep rising, or keep falling, forever without ever resetting.

## Delay

Clean, tape, bucket brigade, granular and ping-pong echoes.

- [Lucento](/engines/lucento/index.md) (free, `org.sournd.delay.lucento`): Clean digital echo: every repeat an exact copy, trimmed by low and high cut in the loop. Set the time in milliseconds or lock it to a note of the host tempo (the Tempo control stands in without one). Changing the time crossfades to the new echo instead of bending its pitch. Offset delays the right side for width. Sync: 0 = free, 1 = 1/32, 2 = 1/16T, 3 = 1/16, 4 = 1/16D, 5 = 1/8T, 6 = 1/8, 7 = 1/8D, 8 = 1/4T, 9 = 1/4, 10 = 1/4D, 11 = 1/2, 12 = 1/2D, 13 = 1 bar.
- [Driftel](/engines/driftel/index.md) (free, `org.sournd.delay.driftel`): Warm, wandering echo. Repeats bend in pitch, soften and saturate as they fade.
- [Backwash](/engines/backwash/index.md) (paid, `org.sournd.delay.backwash`): Backwards echo: every chunk of time is played back reversed during the next one, so notes swell in from nothing and cut off. Feedback flips the repeats back and forth. Fade sets how soft each chunk's edges are. Sync: 0 = free, 1..13 = 1/32 to 1 bar (chunks longer than 2 s are held at 2 s).
- [Bucketta](/engines/bucketta/index.md) (paid, `org.sournd.delay.bucketta`): Dark, gritty analogue-style echo. Short times stay bright, long times get murky because the virtual clock slows down; a compander makes hiss and grit swell and fade with the playing; turning the time bends the repeats in pitch, and the glide sets how fast. Sync as the other echoes: 0 = free, 1..13 = 1/32 to 1 bar.
- [Graniel](/engines/graniel/index.md) (paid, `org.sournd.delay.graniel`): Granular echo: the delayed sound is cut into short grains, scattered in time by Spray, pitched and panned, and layered at the chosen density, from a shimmering cloud to a stuttering glitch. Feedback feeds the cloud back into itself; Freeze (on above half) stops recording so the grains keep playing the held sound. Sync: 0 = free, 1..13 = 1/32 to 1 bar.
- [Tapsody](/engines/tapsody/index.md) (paid, `org.sournd.delay.tapsody`): Rhythmic multi-tap echoes that fan out across the stereo field, even, speeding up or slowing down.
- [Volleto](/engines/volleto/index.md) (paid, `org.sournd.delay.volleto`): Stereo ping-pong. Repeats bounce left and right, thinning and blurring into a wash as they go.

## Reverb

Rooms, halls, plates and spaces that do not exist.

- [Roomette](/engines/roomette/index.md) (free, `org.sournd.reverb.roomette`): A real-sounding room: distinct early reflections that place a sound at a distance, with a short soft tail.
- [Coilette](/engines/coilette/index.md) (free, `org.sournd.reverb.coilette`): Spring reverb: a boingy, splashy tank whose echoes chirp downward as the lows lag behind the highs. Tension tightens the springs (shorter, brighter, less chirp); Drip is how hard transients shake the tank; Springs sets how many are in it.
- [Aulana](/engines/aulana/index.md) (paid, `org.sournd.reverb.aulana`): Lush, slowly moving hall. Separate low and high decay let the tail stay warm and dark or open and airy.
- [Blossa](/engines/blossa/index.md) (paid, `org.sournd.reverb.blossa`): Reverb that blooms: it swells in behind notes, steps aside while you play, and can be gated shut for a hard stop.
- [Shimmerhall](/engines/shimmerhall/index.md) (paid, `org.sournd.reverb.shimmerhall`): Shimmer reverb: a long, gently moving space whose tail is pitch-shifted and fed back into itself, so held notes bloom into a bright halo an octave or a fifth above. Shimmer sets how much climbs. Interval: 0 = octave up, 1 = fifth up, 2 = octave and fifth, 3 = octave and octave-plus-fifth, 4 = octave down and up.
- [Tesselle](/engines/tesselle/index.md) (paid, `org.sournd.reverb.tesselle`): Bright, dense sheet of reverb that builds almost instantly. Smooth on drums and vocals.

## Pitch

Octaves, shifters and harmonisers.

- [Octunder](/engines/octunder/index.md) (free, `org.sournd.pitch.octunder`): Analogue-style sub octaves: square-wave subs one and two octaves down that answer instantly and follow your dynamics, rounded by a tone control. Single notes only, like the circuits it is modelled on in spirit.
- [Swoopline](/engines/swoopline/index.md) (free, `org.sournd.pitch.swoopline`): Octave up straight from the waveform: glassy and clean on one side, ringing and fuzzy on the other, with drive, a gate that trims the tails and a tone control. No latency.
- [Northnote](/engines/northnote/index.md) (paid, `org.sournd.pitch.northnote`): Pitch correction for voices and single-note lines: pulls every note to the nearest note of your key and scale (chromatic, major, minor, pentatonics or your own 12-note set) at a speed from natural to a hard snap at 0 ms, with humanise to leave held notes and vibrato alone.
- [Octrel](/engines/octrel/index.md) (paid, `org.sournd.pitch.octrel`): Clean polyphonic octaves: a sub, a second sub and an octave up that follow chords, with their own levels, a darkening filter for the subs and a squash that keeps the octave voices even.
- [Tessarine](/engines/tessarine/index.md) (paid, `org.sournd.pitch.tessarine`): The everything pitch engine: four voices from three octaves down to three up with fine tune, level, pan and delay each; chord-friendly or single-note mode, formants kept or moved, detune spread and a feedback path that climbs in cascades.

## Performance

Tape stops, stutters, gates and live tricks.

- [Torpora](/engines/torpora/index.md) (free, `org.sournd.performance.torpora`): Tape stop: the sound slows down and drops in pitch to a halt over the stop time, then spins back up over the start time (0 = cut straight back in). Curve bends the slowdown from a sudden drag (negative) to a long coast (positive). Trigger: 0 = the Stop control (on above half), 1 = the host transport stopping and starting, 2 = either.
- [Carvello](/engines/carvello/index.md) (paid, `org.sournd.performance.carvello`): Beat slicer: each bar is cut into equal slices, and Shuffle is the chance that a slice is replaced by an earlier slice of the same bar (Reverse the chance it plays backwards), so loops are broken up and rebuilt on the fly. Hold keeps one pattern for every bar (above half) instead of a new one each bar. Slices: 0 = 4, 1 = 8, 2 = 16, 3 = 32 per bar. Seed picks the pattern.
- [Glacine](/engines/glacine/index.md) (paid, `org.sournd.performance.glacine`): Sustainer: turn Hold on and the current sound is captured and held indefinitely as a smooth, evolving texture, blended under or over the live signal. While held, the trigger decides when it crossfades to a fresh capture: 0 = manual (only when Hold is switched on), 1 = new note (a stable pitch change larger than Pitch change), 2 = transient, 3 = every N beats, 4 = every N bars (host grid, or the Tempo control without one). Switching Hold off lets the held sound die away over Release.
- [Rippet](/engines/rippet/index.md) (paid, `org.sournd.performance.rippet`): Grid stutter: once per interval, at the offset, it rolls the dice and may grab a short slice and stutter it for the gate length, each repeat optionally dropping in pitch and level. Locks to the host grid; without one it runs on its own Tempo. Interval: 0 = 1 beat, 1 = 2 beats, 2 = 1 bar, 3 = 2 bars, 4 = 4 bars. Offset and Gate count sixteenth notes. Repeat: 0 = 1/32, 1 = 1/16, 2 = 1/8, 3 = 1/4, 4 = 1/2. The same seed and song position always make the same decision.

## Utility

Width, routing, polarity and gain staging.

- [Gain](/engines/gain/index.md) (free, `org.sournd.utility.gain`): Clean level control with a short de-zipper ramp.
- [Keelson](/engines/keelson/index.md) (free, `org.sournd.utility.keelson`): Channel utility: flip polarity per channel, swap channels, fold to mono (sum, left or right), balance or pan with a choice of pan law, delay each channel by samples plus milliseconds for time alignment, remove DC, and trim the level.
- [Breadth](/engines/breadth/index.md) (free, `org.sournd.utility.breadth`): Stereo width from mono to double width, with a low end that folds to mono below a chosen frequency.
- [Meridel](/engines/meridel/index.md) (paid, `org.sournd.utility.meridel`): Mid/side mixer: set the centre and the sides separately, spread or narrow the image, and turn the whole image left or right without losing energy. Decode mode takes a mid/side recording in; encode mode sends mid/side out.
- [Spherel](/engines/spherel/index.md) (paid, `org.sournd.utility.spherel`): Binaural panner for headphones: places the input around the listener's head by azimuth, elevation and distance, with the time and level differences between the ears, the head's shadow, a pinna cue for height and softer highs from behind and far away.

## Analysis

Meters, tuners and detectors. Audio passes untouched.

- [Plumb](/engines/plumb/index.md) (free, `org.sournd.analysis.plumb`): Level meter: per-channel sample peak with a falling needle, RMS and a peak hold. Audio passes untouched.
- [Tunra](/engines/tunra/index.md) (free, `org.sournd.analysis.tunra`): Chromatic tuner: the nearest note, how many cents sharp or flat, the frequency and how sure it is, against an adjustable A4. Audio passes untouched.
- [Heft](/engines/heft/index.md) (paid, `org.sournd.analysis.heft`): Loudness meter: momentary (400 ms), short-term (3 s) and gated integrated loudness in LUFS, loudness range and 4x-oversampled true peak, against a target. Audio passes untouched.
- [Huescope](/engines/huescope/index.md) (paid, `org.sournd.analysis.huescope`): Spectrum meter: 31 third-octave band levels from 20 Hz to 20 kHz with an optional display tilt, plus peak and RMS. Audio passes untouched.