Authoring an FX sound

An FX sound is not an instrument. It is a gesture: a riser that lifts into a drop, an impact that marks a section, a sweep that carries a transition. Nobody plays a melody with it. You place one note, and the sound does the rest.

That changes how you build it. Every other guide here shapes a note that repeats consistently every time you press a key. Here the whole point is a single long event that never has to be played twice, so the envelope times run to seconds and the modulation is the sound rather than a detail on top of it.

The page still walks the same chain as every other build, oscillator to filter to envelope to movement to effects, because the signal path does not change just because the intent does. What changes is which end of each band you want. Read the base build below as the shared frame, then take the variant for the gesture you are making.

Each control below gets a start value and a range to try, and each entry says what happens when you cross an edge. The ranges come from what the instrument is, not from a survey of our presets. See how to read these tables for what the provenance tags mean.

Voice

• Voice Mode (production convention). You place one note rather than play a line, so voice allocation looks like it cannot matter. It does, because the envelopes here run to seconds: an impact placed on the downbeat has to keep ringing while the next gesture starts, and in Mono the new note would cut the tail that was the whole sound.

Oscillator

Most of this page is built from noise rather than from a note, which is the first thing that separates an FX sound from every other build in this section. Noise has energy at every frequency and no pitch at all, so a filter always has something to reveal and nothing has to stay in key with the track.

• Noise Level (production convention). Noise is the raw material for most of this page, which is what separates an FX sound from every other build here. The others start from a pitch. Noise has energy at every frequency and no pitch at all, so there is always something for a filter to reveal and nothing that has to stay in key with the track. Turn it down and add an oscillator when the gesture needs to belong to the harmony.
• Noise Cutoff (production convention). Open, so the filter downstream has the whole spectrum to work with. This control and the filter cutoff do similar jobs, so set this one wide and shape with the filter, which is the one the envelopes and LFOs are routed to. Narrowing both leaves the sweep nothing to sweep.
• Osc1 Semi (production convention). Centred, because it is the destination of a modulation rather than a value you set. The riser variant routes a Mod Envelope to this control precisely because Semi spans twelve semitones where Tune spans only one: a riser needs a real climb, not a few cents of drift. Leaving it at zero gives that climb its full range in both directions.

Filter

• Filter Type (production convention). A steep low-pass, because the gesture on this page is usually a filter opening and a steep slope makes that opening dramatic rather than gradual. BP is the choice for a riser that should sound like it is being squeezed through something, and HP24 for a gesture that thins out as it climbs instead of filling up.
• Filter Cutoff, when Filter Type is LP24 or HP24 (production convention). Low, and this is a starting point rather than a setting: it is where the sweep begins. Every gesture on this page moves this control, so what matters is that it starts with somewhere to travel. Set it open and a riser has nothing left to reveal.
• Filter Reso (production convention). High, and this is the one page where that is straightforwardly correct. Every other build here keeps resonance down because a singing peak competes with the note. There is no note. The peak sweeping upward is the entire gesture, and it is what makes a riser audible over a full arrangement. Past about 75% it self-oscillates into a whistle that no longer tracks what you routed to it.

Amp envelope

• Attack (production convention). The widest band of any envelope row on any page here, and deliberately so: this single control is what separates the gestures. Long is a riser, where the attack IS the build, and at 120 BPM two bars is 4 s and four bars is 8 s. Instant is an impact. There is no useful middle, so pick a variant below rather than a value here.
• Decay (production convention). Long, because an FX sound is a single event that is allowed to take its time. Nothing has to be played after it in the way a melody has a next note.
• Sustain (production convention). Full, so a held gesture stays up while the modulation does the work. This is the opposite of the reasoning on every acoustic page, where sustain describes whether the instrument has an energy source. Here it decides whether the sound waits for you or leaves on its own, and a riser has to wait for the downbeat.
• Release (production convention). Short at the start value, so the gesture cuts away cleanly on the downbeat, which is the moment it exists to set up. The impact variant is the exception and takes the top of this band, because there the tail is the sound rather than a loose end.

Movement

Movement over the note: no shape is prescribed (production convention).

An effect sound is defined by its gesture, and the gesture differs entirely between one effect and the next: a riser climbs, an impact collapses, a sweep passes through. There is no shape the category shares, so declaring one would be inventing a rule rather than recording one.

How to build it: Pick the shape the gesture needs. The audit reports what each preset does here and asserts nothing.

The modulation is not a detail on top of an FX sound, it is the sound. Mod Env 1 drives the climb, and its shape has to agree with the amp envelope: if the two disagree the gesture gets loud before it gets bright, or the reverse, and it stops reading as one event.

• ModEnv1 Atk (production convention). Match this to the amp attack, because the two are describing the same build. The amp envelope brings the level up and this one drives the filter and pitch climb, and if they disagree the sound gets loud before it gets bright, or the other way round, and the gesture stops reading as one event.
• ModEnv1 Sus (production convention). Full, so the climb holds at the top rather than sliding back down while you are still waiting for the downbeat. A riser that peaks early and decays is the most common way to build one that does not work.
• Mod Env 1 to Filter Cutoff (production convention). The climb, and the routing this whole page is built around. The filter opens across the length of the gesture. Deep, near the top of what a routing can ask for, because the sweep has to cross most of the spectrum to be heard as a build rather than as a slight brightening.
• LFO1 Sync (production convention). Locked to the tempo. Anything rhythmic in a transition has to land with the track, because the gesture exists to set up a specific downbeat. This is also what makes the accelerating riser work: with sync on you set a division rather than a rate, and the pulsing stays in time as it speeds up.

Effects

• Reverb Size (production convention). Large. There is no transient to blur and no rhythm to smear, which are the two reasons every other page keeps the room small. A transition is meant to sound like it is happening somewhere bigger than the track.
• Reverb Mix (production convention). Wet, and the impact variant takes it further still. On this page the room is not an effect placed on the sound: for an impact it is most of the sound, because the dry hit is over in a moment and what you hear for the next several seconds is the room answering it.
• Delay Sync (production convention). Locked, for the same reason the LFO is. An unsynced repeat in a transition lands somewhere arbitrary, and a transition is entirely about where things land.

Variants

Build the base sound above, then apply the overrides below. Everything not listed stays as it was.

Three of the four are articulations: riser, impact and sweep are the same material moving in three different ways. Glitch is a timbre, so it says what the sound is made of rather than how it moves, and it composes with any of the other three. A glitchy riser and a glitchy impact are both real sounds, and each is built by taking glitch plus one articulation. Taking two articulations is not meaningful, because a gesture moves one way.

Riser

How the note speaks (articulation). Everything not listed below is unchanged from the base fx. A preset claims this band by declaring "articulation": "riser" in its tags; until it does, the base band still applies to it.

A riser climbs for several bars and hands over to whatever comes next. It is the base build taken to its long extreme: the attack is the length of the build, and everything else follows. The routing that matters most is the second one below, to Osc 1 Semi rather than to Tune. Semi spans twelve semitones where Tune spans only one, and a riser needs a real climb rather than a few cents of drift. For the accelerating version, route Mod Env 1 to the LFO Rate as well, so the pulsing speeds up as the sweep rises, which is what makes a build feel like it is running out of time.

• Attack (production convention). The attack IS the riser: set it to the length of the build, and count it in bars rather than seconds. At 120 BPM two bars is 4 s and four bars is 8 s. Get this wrong and no amount of routing rescues it, because the gesture arrives early or late at the one moment it exists for.
• Release (production convention). Short. The riser has to disappear the instant the drop lands, leaving the downbeat to whatever it was building towards. A tail here is the sound overstaying, and it muddies exactly the moment it spent eight bars setting up.
• Mod Env 1 to Osc1 Semi (production convention). The pitch climb that runs under the filter climb. Routed to Semi rather than Tune: Semi spans twelve semitones and Tune spans one, so the same depth on Tune gives a rise the ear reads as unsteady tuning rather than as a rise at all. Past about 60% the climb runs off the top before the build is finished.

Impact

How the note speaks (articulation). Everything not listed below is unchanged from the base fx. A preset claims this band by declaring "articulation": "impact" in its tags; until it does, the base band still applies to it.

The opposite gesture: everything at once, then a long tail. An impact marks a downbeat rather than leading up to one, and it is mostly reverb. The dry sound is over in a moment, and what you hear for the next several seconds is the room responding to it. For a downlifter, the impact that falls away rather than blooming, route Mod Env 1 to Osc 1 Semi at a negative depth so the pitch drops through the floor as the hit decays. For the hard 1980s version, turn Reverb Gate up so the tail is chopped the moment the input stops.

• Attack (production convention). Instant. An impact that takes even a few milliseconds to arrive is heard as landing late, because it is competing with a drum hit on the same downbeat and the ear resolves the two by whichever speaks first.
• Decay (production convention). The long tail is the sound. Everything the gesture does happens after the moment it arrives.
• Sustain (production convention). Zero, unlike the base build. A riser waits for you to release it; an impact is over whether you hold the key or not, so the decay above has to be the whole shape and nothing may hold it up.
• Reverb Mix (production convention). Past halfway, which would be a mistake anywhere else on any page. The proportion is the instrument here: an impact is a short excitation of a large room, so the room has to be louder than the thing exciting it.
• Reverb Size (production convention). As large as it goes. The tail length is what makes the hit feel like an event rather than a drum, and size is what buys it.

Sweep

How the note speaks (articulation). Everything not listed below is unchanged from the base fx. A preset claims this band by declaring "articulation": "sweep" in its tags; until it does, the base band still applies to it.

A transition that passes over the whole track rather than sounding on its own. Here the effects are the instrument: instead of an envelope shaping a note, a phaser's notches move across whatever is playing. That makes it the one gesture on this page you perform rather than trigger. Stop the phaser sweeping on its own, then move its centre by hand from the mod wheel, or draw the move with an MSEG if it has to be the same every time.

• Phaser Rate (production convention). Zero, and that is the entire trick. At any other value the phaser sweeps on its own schedule and the notches are a cyclic effect. At zero they stop, and the centre frequency becomes a control you move, which turns a repeating wobble into a gesture that happens once at the moment you choose.
• Phaser Mix (acoustic fact). Fifty percent, and this one is arithmetic rather than taste. A phaser works by cancelling the phase-shifted signal against the dry one, so the notches are deepest where the two are equal. Take the mix to full wet and there is nothing left to cancel against, so the notches vanish at exactly the setting that sounds like it should be the strongest.
• Phaser Center (production convention). Low at the start, because this is where the sweep begins rather than where it sits. The band is the distance the gesture travels: from down under the body of the track up into the air above it, which is what makes a sweep feel like something passing over.
• Mod Wheel to Phaser Center (production convention). The routing that makes the gesture yours to perform. Deep, near the maximum, because a sweep that only covers part of the spectrum reads as a filter wobble rather than as a transition. Swap the mod wheel for an MSEG when the move has to be identical every time the section comes round.

Glitch

What the note is made of (timbre). Everything not listed below is unchanged from the base fx. A preset claims this band by declaring "timbre": "glitch" in its tags; until it does, the base band still applies to it.

The one variant here that says what the sound is made of rather than how it moves, which means it composes with the three above: a glitchy riser and a glitchy impact are both real sounds, and both are built by taking this and one of those. Decimate is the reason. It is sample-rate reduction rather than a clipping curve, so it is the sound of something breaking rather than of something being driven hard, and that digital failure is a material in its own right. Route Step Sequencer 1 to the filter cutoff with its division at 1/16 for per-step jumps that are rhythmic rather than random, or Sample and Hold to the same target when you want them unpredictable.

• Dist Mode (production convention). Decimate rather than a clipping curve, and the distinction is the variant. Soft Clip and Hard Clip make a sound louder and rounder or harsher: they are still the same sound, driven. Decimate throws away samples, so what you hear is aliasing, which is a failure rather than a colour. Bit Crush is the same idea applied to amplitude instead of time and is the alternative when the grit should be steady rather than bright.
• Dist Drive (production convention). In Decimate mode this reads as sample-rate reduction rather than as gain, so it sets how broken the sound is rather than how loud. Below about 20% the aliasing is too faint to be a timbre and just sounds like a slightly dull effect. Past about 70% the original gesture is unrecognisable, which is occasionally what you want and never what you want by accident.
• Stutter Bypass (Kiwisynth-specific, our judgment). The Stutter effect is off in a new sound, and it is what turns a glitch into a fill: it catches a step of the sound on the beat and repeats it. Its defaults already make the classic placement, the last beat of every bar, so switching it on is most of the move.
• Stutter Grid (production convention). Glitch repeats live at 1/16 and 1/32: a step that short repeats as a machine stalling rather than as a phrase echoing back. At 1/8 the repeat is long enough to hear what was caught, which is the edit-style stutter rather than the buzz, and the right choice when the sound under it is melodic.
• Stutter Ramp (production convention). The accelerating roll of edit-style stutters: each repeat shorter than the last, so the fill speeds up into the downbeat. At 0 the repeats stay on the grid, the plain beat-repeat sound. Past about half the steps reach their shortest within a few repeats and the roll collapses into a flat buzz, which is a different effect and rarely the one wanted.

A gesture is judged in place and never on its own. Play the sound against the bars it is meant to lead into, because the only question that matters is whether the downbeat lands better with it than without it.