No-Input & Feedback
Building self-oscillating feedback instruments inside Live 12 — return-to-self routing, Roar Feedback, Echo past 100 %, resonator self-oscillation, eurorack loopback — with safety first and a Feedback Machine rack.
No-input music is the practice of making sound from a signal path with nothing at the start of it: a mixer's output fed back into its own input, a delay regenerating its own noise floor, a filter ringing on its own resonance. The instrument is the loop and the performer plays its gain, filtering and timing. Physically a feedback loop with gain ≥ 1 at any frequency grows until something limits it, and the loop's filtering decides which frequency wins; everything you do is about choosing the limiter and shaping that selection. In Live 12 this is entirely possible in the box — Live allows returns to send to themselves, tracks to listen to other tracks and returns, Roar has a dedicated Feedback section, and Echo, Grain Delay and the resonators all go past unity. It is also the most dangerous page on this site for your ears and tweeters. Read the safety section first and build the limiter before the loop. Reference points for style only: Toshimaru Nakamura's no-input mixing board (tonal, patient, pure feedback tones), Merzbow (density, distortion stacks), the "feedback techno" of generative kicks from a loop that pulses on its own.
Safety first (build this before anything else)
- Limiter at the exit of the loop, not only on the master. A loop at +30 dB internally will hit the master limiter and duck everything else; a limiter at the loop's output keeps the damage local. Ceiling −3 to −6 dB. Set the Limiter before you close the loop.
- Saturator with Soft Clip enabled before the limiter: the growth of a feedback tone through a soft clipper is musical (it flattens into a square-ish drone); through a hard limiter alone it pumps.
- A limiter inside the loop too (Utility or Limiter in the feedback path) bounds the internal gain so the loop sustains instead of exploding. The sweet spot for most no-input sounds is loop gain hovering around unity, which only a limiter inside the loop makes stable.
- Monitoring volume down 12 dB before closing any loop. Feedback onsets are sudden. Push encoder mapped to a Utility gain is your physical fader; keep one hand on it.
- Gain staging: loops amplify everything, including the −90 dB noise floor and DC. Put an EQ Eight HP at 30 Hz in every loop, and a Utility with DC removal if you see a DC offset on the meters (Saturator's DC switch also works).
- Headphones: no. Build these on monitors at low volume; headphones put the explosion directly on your eardrum with no time to react.
Anatomy
- The loop filter is the oscillator. A bandpass in the loop makes a sine-ish drone at the bandpass frequency. A delay in the loop makes a comb: a pitched tone at 1/delay time and its harmonics (10 ms = 100 Hz).
- Gain is the amplitude envelope. Gain just over 1 = slow swell; well over 1 = instant howl; just under 1 = decaying ring. Automating gain across unity is how you "play" it.
- Nonlinearity makes it interesting. A pure linear loop produces a pure tone. A Saturator, Roar or Redux inside the loop produces harmonics, which feed back, which produce more — chaos is in the clipper.
- Latency = pitch. Live's internal track-to-track feedback has at least one buffer of delay (your audio buffer size); at 128 samples / 44.1 kHz that's 2.9 ms, i.e. a 344 Hz comb. Change the buffer size, change the fundamental. Add a Delay device to tune it.
Recipes
Return track sending to itself (the basic Live no-input loop)
Live's returns can send to other returns and to themselves (enable it in the return's own send knob, which is greyed until you right-click → enable). This is the simplest closed loop in Live: a return whose devices process its own output, forever.
- Create a return track (Cmd+Alt+T). In the return's mixer section, right-click the Send A knob (its own send) and Enable Send. Set it to −inf for now.
- Build the chain in the order above. The Limiter (ceiling −6 dB) at the end is mandatory. Monitoring volume down.
- Excite the loop: send any track to Return A for one beat (a single kick, a click, your voice), or just raise the send-to-self — the device noise floor is enough to start it.
- Raise the self-send slowly from −inf. Around −8 to −3 dB (depending on the Saturator drive) the loop crosses unity: a tone emerges at the bandpass frequency, coloured by the 23 ms delay comb (43 Hz series). Back off the send to −10 dB and it decays over seconds — you are playing the envelope.
- Now play the Auto Filter frequency: the drone follows the bandpass. Res higher = purer tone; lower = noisier, broader howl. Saturator drive = harmonic content. Delay time = comb pitch (use Delay's unsynced mode; sync it to the tempo for rhythmic loops).
- Map self-send, filter freq, filter res, Saturator drive and Delay time to five Push encoders; that's the instrument.
| Parameter | Value | Why |
|---|---|---|
| Self-send level | −12 → −2 dB (ride it) | Loop gain; unity crossing is where tones are born |
| Loop HP / LP | 60 Hz / 6 kHz | Keeps the loop out of sub and tweeter territory |
| BP resonance | 20–50 % | Tone purity; above 60 % the filter alone may self-oscillate |
| Delay time | 5–50 ms unsynced | Comb fundamental 200–20 Hz; tune by ear |
A return sending to itself is a recirculating delay line whose delay is one audio buffer plus the Delay device. The filter picks which comb harmonic has gain > 1 first; that harmonic grows, the Saturator clips it, the clipping generates harmonics that are themselves filtered — the loop settles into a limit cycle, which is the "note".
Live's own self-send on returns is intentional and safe when the Limiter is in place, but if you also route a track into the return and the return's output into that track (via Audio To → track), you've created a second, unlimited loop. One loop at a time until you know what each does.
Audio track listening to its own return or to Resampling
The second route: an audio track whose input is a return (or the master via Resampling) that it itself feeds. Different from the self-send because the track's devices and the return's devices form a loop across two channels, and because Monitor In introduces a controllable latency.
- Audio track, Audio From: Return B (tracks can take input from returns in the input chooser), Monitor In. Send A/B on this track: send B at 0 dB. Return B's output to Master. Loop closed.
- Return B: Hybrid Reverb (Dark Hall, 3 s, 60 % wet), HP 80 Hz, Limiter −6 dB. Reverb in the loop turns the comb into a cloud — pitches smear into a wash instead of one tone.
- Track 1: Roar in Single routing, Soft Sine shaper, Drive 10 dB, post-filter LP 3 kHz. Grain Delay with +0.3 st pitch shift and 10 ms spray: each pass through the loop drifts the pitch slightly, so the tone never settles. Utility gain is the loop gain control.
- Raise Utility gain from −20 dB. The reverb tail of the noise floor grows into a drone within a few seconds. Roar's drive sets how hard it clips.
- Resampling variant: track input = Resampling (the master output) with Monitor In; now the loop includes the whole mix, and whatever else is playing excites it. Keep the send-to-master chain limited; this one is ideal for "the track feeds back on itself" moments in a live set — Utility gain up for 4 bars, down.
Record the audio track (arm, record) while playing the loop: Live records the loop's own input, i.e. the return, giving you the feedback as audio for later resampling. See routing & resampling.
Monitor In + Audio From a return + send to that return = loop, but also a loop whose latency is twice the audio buffer plus the plugin delay compensation. Live's Delay Compensation may add hundreds of ms if any device in the loop reports latency (Hybrid Reverb Convolution, Multiband Dynamics, Limiter with lookahead). Reduce the Limiter's lookahead or accept the longer comb.
Hardware no-input mixer and eurorack loopback through External Audio Effect
The real thing: a hardware mixer with an aux send patched back into a channel input, or a eurorack feedback patch (Mojave → Data Bender → Nautilus → back into Mojave's input), inserted into a Live chain via External Audio Effect so Live's filters, limiters and recording are around it.
- Hardware mixer no-input: patch an aux send output to a channel input, channel aux send up, main out to the interface. The channel EQ is the loop filter, the aux knob is loop gain, the channel fader is the output. Bring the mixer's main out into Live via External Audio Effect (Audio From the interface inputs) with Live's Limiter after it.
- Eurorack loop: Nautilus (delay/feedback) output → Data Bender (glitch/buffer) → Mojave (granular) → VCA → back into Nautilus's input. Mojave's grain density and Data Bender's corruption are nonlinear elements in the loop; Nautilus's feedback and the VCA level set loop gain. A filter (any VCF) in the loop selects the pitch.
- External Audio Effect on an audio track: Audio To the output pair that feeds Nautilus's input (so Live can inject pulses or a kick into the loop), Audio From the pair that receives the loop output. Hardware latency compensation: set it by ear or with the Latency measurement; in a feedback loop the latency itself is the pitch, so it is not something to "fix".
- Excite from Live: a 1-bar MIDI clip into a short noise burst (Operator Noise, 20 ms) sent out through the External Audio Effect. Each burst restarts the loop; with the eurorack feedback just under unity you get a hit that rings into chaos and dies — a generative percussive voice.
- Record the External Audio Effect's return via Resampling or by arming an audio track listening to the hardware input. Everything in the loop is one-time; the recording is the composition.
CV Tools (CV Triggers, CV Utility) over a DC-coupled interface can open the VCA from Live, so the loop gain becomes a Live envelope: a kick-shaped CV into the feedback VCA gives feedback percussion that follows the arrangement. See hardware & modular integration.
Hardware feedback has no Limiter. Keep the mixer's main fader low, the interface input gain low, and never patch a loop with headphones on.
Roar's Feedback section as a self-contained no-input synth
Roar has an internal feedback path with its own delay time (expressed as pitch), gain and the shaper inside the loop. With no input, high Feedback and some Drive, Roar sings on its own — a tuned, overdriven feedback oscillator with a modulation matrix.
- Roar on an audio track with nothing playing. Choose the Feedback routing. Feedback amount to 80 %, feedback Pitch (the loop delay expressed as a note) to C2 — the loop length is now the period of a 65 Hz tone.
- Shaper stage 1: Soft Sine, Drive 15 dB. Pre-filter LP 2 kHz (filters in the feedback path select the harmonic). With gain high enough the device's own noise floor starts a tone at C2 within a second; if it doesn't, feed one click (a 1-sample MIDI-triggered Operator Noise burst) and it takes off.
- Now it's a synth: the feedback Pitch is the oscillator pitch, so automate it in semitones or modulate it with Roar's LFO (small amount = vibrato; large = sirens). Roar's Envelope Follower on its own output → Drive makes the tone fight itself: louder = more drive = more harmonics = filter passes less fundamental = quieter. Self-regulating growl.
- Change shaper type for timbre: Fold = hollow and glassy, Rectify = octave-up buzz, Bit Crush = digital screams, Diode = asymmetric and warm. Each clipper's shape changes which harmonics the loop favours.
- Add Roar's Noise modulation source → Feedback amount at 10 % for a tone that wavers and occasionally breaks up.
| Parameter | Value | Why |
|---|---|---|
| Feedback amount | 70–100 % | Below ~70 % with these drives, the loop decays; above, it sustains |
| Feedback pitch | C1–C4 | Loop delay = 1/f; sets the fundamental |
| Drive | 10–20 dB | More drive = earlier onset, squarer tone |
| Pre-filter | LP 1–3 kHz | Removes aliasing-like high harmonics from the loop |
Roar's feedback path is a Karplus-Strong-style delay loop with a nonlinearity. Because the delay is tuned, the result is a pitched oscillator; because the nonlinearity is a shaper, the harmonic content depends on level. It is a physical model of a howling amp without the amp.
Variations: put Roar in Feedback routing on a kick: feedback 60 % tuned to the kick's root; each hit rings into a pitched growl that decays before the next. This is the "feedback 808".
Echo feedback above 100 % and the Hybrid Reverb → Echo loop
Echo's feedback control goes past unity deliberately. With the feedback filter narrowing the band and the Character section adding drift, Echo on its own becomes a tape-feedback oscillator; add a reverb in series on the same return and the oscillation becomes an orchestra.
- Echo on a return. Feedback 100–110 %. Feedback filter HP 150 Hz, LP 2.5 kHz — narrow it further for a more tonal result. Echo's internal path already limits softly; the external Limiter is still mandatory.
- Modulation 10–20 % at a slow rate detunes each repeat slightly so the oscillation chorus-drifts rather than locking to one pitch. Noise 15 % and Wobble 20 % (Character section) add tape-floor hiss and flutter that get amplified into the texture.
- Send one hit into it. Within 8–16 repeats it stops decaying and starts climbing; the Saturator holds it. Ride Feedback between 95 and 108 % to play the swell/decay.
- Hybrid Reverb before Echo on the same return makes every repeat more diffuse than the last; with the return's self-send at −20 dB you get an outer loop whose period is the audio buffer plus the reverb's pre-delay — a second, slower tide underneath the delay's rhythm.
- Echo's Duck/Gate section on the return, triggered by the kick, keeps the feedback drone out of the way of the beat when this is used in a track.
Sync the delay times (1/8 and 3/16) and the oscillation becomes rhythmic: a dub-techno engine that plays itself. Automate the feedback filter frequency across 16 bars and it "modulates" through chords of its own.
Self-oscillation: Auto Filter resonance, Corpus/Resonators, Spectral Resonator
Devices that ring are already feedback loops; push them to the edge and they oscillate without input. Each one gives a different oscillator.
- Auto Filter: switch the circuit to MS2 or SMP (the analog-modelled types, selectable in the 12.2 redesign), Resonance 100 %, Drive up. The filter self-oscillates with a sine at the cutoff — a one-knob oscillator. Automate frequency in semitones with the Envelope Follower or an LFO device for melodies; a click excites it faster.
- Corpus: Resonance type Tube or String, Decay 100 %, low Material (damping): a single click rings indefinitely at the tuned pitch. Tune by MIDI sidechain so it follows a bass line — each new note re-tunes the ringing without retriggering.
- Resonators: Decay 100 % with Const on and all five resonators at intervals (root, 5th, octave, 10th, 12th): one click = a sustained chord forever. Feed it a 1/16 click pattern and the chord breathes.
- Spectral Resonator: Freeze holds the current spectrum; Decay at maximum and Unison high make it an infinite pad. Set the Frequency Shift slowly moving (0.1 Hz) so the frozen chord slides through inharmonic tunings.
- Chain all four for an organ of ringing things; a click track plays them; the Limiter stops the sum from running off.
A resonant filter at maximum resonance has a pole on the unit circle: gain is exactly 1 at the cutoff frequency, so any energy there persists forever. The ringing resonators are the same thing at several frequencies. These are "feedback" oscillators with the loop hidden inside the device.
Decay 100 % on Resonators or Corpus plus a continuous input never stops accumulating. Keep the Saturator soft clip in place and automate Decay down to end phrases.
Grain Delay feedback and Looper overdub decay
Two more loops with character: Grain Delay's feedback with a pitch offset climbs or sinks by that interval each pass; Looper's overdub feedback is a loop whose period is bars, not milliseconds.
- Grain Delay: Feedback 90–98 %, Pitch +0.5 st. Every repeat is a quarter-tone higher; over 20 seconds a single note becomes a slowly rising cluster. Random Pitch 5 % and Spray 20 ms blur it into a cloud. Pitch −0.5 st sinks it. Pitch exactly +12 with Feedback 95 % gives the "infinite octaves" shimmer.
- Looper after it: 4-bar loop, Feedback 85 %, leave it in overdub. Each pass fades the oldest layer by 15 %; the cloud from Grain Delay is captured and re-captured, so the Looper itself becomes a slow feedback loop whose "pitch" is the loop length. Record, overdub, and the texture evolves by itself.
- Looper's Reverse and ½ speed buttons mangle the whole accumulated loop; with Feedback at 85 % the mangled version becomes the new base within a few passes.
- Looper's output can be sent to Grain Delay's input (Looper on a track, Grain Delay on a return, return self-send off, track sends to return, return output Audio To the Looper track) for a true outer loop: bar-scale feedback through a ms-scale feedback. This is the ambient engine.
Map Looper's feedback and Grain Delay's pitch to two Push encoders: pitch at 0 holds, +0.5 rises, −0.5 falls, and Looper feedback at 100 % freezes the current state, under 80 % lets it die. The whole performance fits in two knobs.
Generative no-input techno: kicks, bass and textures from one loop
A loop that pulses on its own is a kick drum. A loop filtered at 60–150 Hz with an Envelope Follower modulating its own gain produces regular self-triggering thumps; higher bands become hats and textures. The track makes its own drums with no sequencer.
- Return D, self-send enabled at −4 dB (over unity once the Saturator drive is in). Auto Filter LP at 90 Hz with resonance 55 %: the loop can only grow at sub frequencies — the tone is a 60–90 Hz thump rather than a howl.
- Saturator Hard Curve, 12 dB, Soft Clip on: the sub tone is squared off into a punch.
- Gate in the loop with a hold of 80 ms and release 120 ms: the loop only passes while it's loud, so once it fires the gate shapes a kick-length envelope and then cuts the loop, which resets it.
- Envelope Follower (Max for Live) on the return's output, mapped to the Utility gain, inverted, range −12 dB: as the loop gets loud the gain drops, so it can't sustain — it collapses and has to charge up again. Rise/fall times of the follower (50 ms rise, 300 ms fall) set how fast it re-fires.
- Delay set to 1/4 synced, feedback 0, inside the loop: now the loop can only reinforce itself once per quarter note, and the pulses lock to the tempo. Switch to 3/16 for a swung pulse. With Delay unsynced at 400–700 ms it free-runs: generative, drifting kicks.
- Duplicate the return with the filter at 2–6 kHz BP, Gate hold 10 ms: self-triggering hats. A third at BP 120–250 Hz with Gate hold 300 ms: a bass that follows its own kick. Three loops, three self-playing instruments, each controllable with one Utility gain. Record them all via Resampling and arrange as normal drums.
This is a relaxation oscillator built from gain and a slow negative feedback (the envelope follower): the loop accumulates energy until the gate/follower cut it off, then recovers. Any slow negative feedback around a fast positive loop oscillates at the slow loop's time constant. The Delay quantises when reinforcement can happen, which is why it locks to tempo.
The Envelope Follower is on the same device chain it modulates: increase its range gradually. Too much inverted gain and the loop never charges (silence); too little and it sustains (howl) instead of pulsing.
Controlling chaos: macros, Envelope Follower, LFO and performance gestures
Feedback instruments are unstable by nature; the work is to find three or four controls that move them between known states, and to let modulators nudge them without letting go of the fader.
- Put the whole loop in an Audio Effect Rack. Macro 1 Gain maps to every loop-gain element at once (self-send can't be in a rack, so map it with the same macro via a MIDI mapping or automate both). Macro 2 Colour: filter frequency + Saturator drive, inverse so brighter is also cleaner. Macro 3 Pitch: Delay time / Roar feedback pitch / Grain Delay pitch. Macro 4 Freeze: in-loop Limiter ceiling down and self-send to exactly unity.
- Envelope Follower from the loop output → Gain macro, inverted, 20–30 %: automatic gain riding. The loop tends toward a stable level you choose with the macro; you play around it.
- LFO device at 0.02–0.1 Hz → Colour macro 20 %: the drone slowly changes harmonic without your hand on it. Use the LFO's S&H shape, retriggered per bar, for stepped changes that feel sequenced.
- Shaper (M4L) drawn as a staircase → Pitch macro, triggered once per bar: the loop steps through a scale of delay times. Set the staircase to intervals of a musical scale in ms (see note to Hz; delay ms = 1000/Hz).
- Macro Variations (Live 12 racks) store 8 states of the four macros: "charging", "sustain", "scream", "collapse". Push's macro variation buttons are then a scene change for the feedback instrument. Macro randomisation with the range limited to Colour and Pitch gives safe surprise; never randomise Gain.
Record every session. Feedback instruments don't repeat; you are documenting, not composing. The best 30 s of a 20-minute session becomes the sample set for the next track.
Turning feedback into drums, bass and textures (resampling workflow)
Once recorded, feedback is just audio with unusual properties: long, spectrally rich, non-repeating. Cut it into drums, tune it into bass, stretch it into beds.
- Drums: record 2 minutes of the generative-kick loop. Slice to a Drum Rack by transient. Each pad's Drum Sampler: short decay, Punch up (12.1 Drum Sampler's transient shaper), Sub tuned to the key for the kicks. Drum Buss glues the inconsistency. You now have a kit made of nothing.
- Bass: find a 1–2 s stable drone segment, load into Simpler Classic mode, Warp off, set loop points on a clean cycle, transpose so the root matches (use Live's Audio-to-MIDI melody conversion to find the pitch, or tune by ear against a sine). Play chromatically; add Saturator and sidechain. Feedback drones have moving harmonics that no oscillator has.
- Textures: the chaotic passages into Granulator III (grain 80 ms, scan slow) or Simpler Texture warp mode stretched 8×; a Spectral Time freeze of a scream held for 32 bars is a pad.
- Hits: the moments where a loop collapses (the gate cutting it) are natural impacts. Reverse the 300 ms before a collapse for the riser into it.
- Everything goes through the normal processing afterwards; the sources are strange but the mix rules aren't. See resampling workflow.
Name the slices with the loop settings that made them (e.g. "fb-kick LP90 res55 drive12"). Feedback kits are irreproducible otherwise.
Processing chain
The generic no-input path, with the loop as a block in the middle and safety on both sides of it. Excitation is optional; the loop will start from its own noise.
Rack
The rack is deliberately two chains in series rather than a parallel rack: the Loop chain is what gets fed back, the Exit chain is what the listener gets. On a return with self-send enabled, the self-send takes the return's output (post-Exit) — so for the loop to run past the limiter's ceiling you set the Exit Limiter above the loop's own operating level, or put the Exit chain on a separate audio track fed from the return. The feedback rack page walks through both layouts with the Push macro map.
Genre variations
| Context | Loop filter | Nonlinearity | Gain behaviour | Output use |
|---|---|---|---|---|
| Nakamura-style no-input (pure) | Narrow BP, Res 60 %, sweeping slowly | Minimal: Saturator Soft Sine 2 dB | Hovering at unity for minutes; swells of 20–60 s | Sine-like tones, beating pairs; as-is, no further processing |
| Merzbow-style noise wall | None in loop (HP 30 only) | Roar Parallel, 3 stages, Bit Crush + Fold + Hard; Redux | Far above unity, limiter working constantly | Full-band; layer 3 loops, mix with EQ only |
| Industrial techno | LP 90–150 Hz Res 50 % (kick loop) + BP 2–5 kHz (hat loop) | Saturator Hard Curve 12 dB | Gated, self-triggering, synced Delay | Resample → Drum Rack; sidechain everything else to it |
| Dub techno | Echo 1/8 + 3/16 synced, feedback filter 200 Hz–2.5 kHz | Echo's own + Saturator 4 dB | Feedback 95–105 % ridden per 8 bars | Chord-like drones; HP 200, sidechain to kick, 30 % in the mix |
| Ambient | Hybrid Reverb in loop, LP 5 kHz | Grain Delay +0.5 st, Looper 85 % | Just under unity: long decays re-captured by Looper | Beds; Spectral Time freeze for sections |
| Dubstep / bass | Roar Feedback pitch at the bass root | Roar Fold / Diode, Drive 15 dB | Triggered per note by MIDI click, decays within the note | Resample to Simpler, play as growl bass |
| Eurorack hybrid | VCF in the hardware loop | Data Bender corruption, Mojave grains | VCA from CV Tools envelope | External Audio Effect → Live limiter → Resampling |
Common mistakes
- Closing the loop before the limiter exists. The first thing in the project is a Limiter; the loop comes second.
- Limiter only on the master. It ducks the whole mix; the loop's own exit needs one.
- No HP in the loop. DC and sub rumble accumulate fastest; 30 Hz HP in every loop.
- Expecting repeatability. It won't repeat. Record everything, always, via Resampling.
- Two loops accidentally. A self-send plus a track listening to that return plus a send back is three loops; untangle until you can draw it.
- Hard limiter with no soft clip before it. Pumping and ugly distortion. Saturator Soft Clip, then Limiter.
- Loop gain as the only control. Tone (filter) and pitch (delay) controls are what make it an instrument rather than an accident.
- Randomising the gain macro. Randomise colour and pitch; never gain.
- Lookahead devices in the loop. Multiband Dynamics, Limiter lookahead and Convolution reverb add latency that Live compensates by delaying everything; in a loop that becomes a pitch and timing you didn't choose.
- Headphones. No.
Related
- Feedback rack — the Feedback Machine built step by step, with the two layouts and the Push map
- Routing & resampling — send-to-self, Audio From returns, Resampling input
- Roar & saturation — Roar's routings and Feedback section in depth
- Modulation & Max for Live — Envelope Follower, LFO, Shaper
- Hardware & modular integration — External Audio Effect, CV Tools, latency
- Drones and Textures, foley & noise — where the output goes
- Generative sounds — more self-playing systems
- Dub FX & delays — Echo feedback as a musical device
- Loudness & limiting and Resampling workflow
- Industrial techno, Ambient, Dub techno