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Best varispeed plugins

Gazillion Industries · September 24, 2026

The same question turns up on plugin forums every few months, in almost the same words: is there a plugin that does what the speed control on a tape machine does, pitch and tempo sagging together, on a fader you can ride?

A varispeed plugin changes playback rate, so pitch and time move together: slow it and the audio gets longer and lower at once. The good ones put that rate on a continuous, automatable control rather than a single button, resample cleanly enough that a speed-up does not go glassy, and are honest about whether the control springs home or holds. Free ones exist. Which you want depends on whether you are transposing a whole session or playing a move into a bus.

The short version

Hear it

Four different things people mean by "varispeed plugin"

The forum threads go round in circles because four unrelated tools answer to the name, and the person asking rarely says which one they want. Sort yourself before you download anything.

A whole-session transpose. The entire arrangement a tone down so a singer can reach it, tempo included, and back again afterwards. That is a host-level job rather than an insert effect. Logic Pro has a Varispeed control built in. Ableton Live has no single control that does the same job, which is why paid Max for Live devices rank on this search at all.

A playable gesture on an insert. Grab a speed control during playback, pull the whole bus down half a semitone into the chorus, let it snap back. This is the literal ask in most of those forum posts, and the narrowest category of the four.

Varispeed inside a tape delay. On a belt-drive tape echo the delay time is set by how fast the motor spins, so changing speed bends every repeat already in the machine. That squealing dive is a different effect from transposing a track, searched under the same words.

Whatever the DAW already does. Turn warping off on a clip and transpose it and you have varispeed: the clip gets longer and lower. Free, immediate, and destructive to the grid, which is exactly why people go looking for a plugin instead. The mechanism is the same in all four cases, and it is covered properly in what is varispeed.

What varispeed actually does to the signal

Playback rate and pitch are the same fact seen twice. Read the samples out faster and every period in the waveform gets shorter, so every frequency goes up by the same ratio and the file finishes sooner. Double the rate for exactly an octave up, halve it for exactly an octave down. One semitone is a ratio of 1.0595, near enough 6%.

That shared ratio is what makes varispeed sound like a machine rather than a process. A pitch shifter moves the notes and leaves the room where it was. Varispeed takes the notes, the room, the hiss, the breath and the formants with them, which is why a voice slowed 8% sounds like a bigger person in a bigger space rather than the same person singing lower. That side effect has its own page: formant shifting.

It also means the two directions fail in opposite ways. Slowing down is forgiving, because everything you need is already in the file. Speeding up is not: content at 14 kHz lands at 15.4 kHz after a 10% lift, and content near the ceiling has nowhere to go but back down the spectrum as a false tone. That is aliasing, and it is the biggest audible difference between a well-built varispeed plugin and a careless one.

What separates a good varispeed plugin from a bad one

Five things, and only the first is obvious.

The control is continuous and automatable. A tape stop button is a preset gesture. A rate you can draw, ride and automate is an instrument. Plenty of plugins sold as varispeed give you the button and call it done.

The resampling is good. Ask for +10% on a bright loop and listen to the cymbals. Grit that was not there before, or a metallic ring that sits still while the music moves, means cheap interpolation. Slowing down will not show you this, so test upward.

The return is designed. Hold a slowdown on an insert and the plugin is handing the host less audio than the host is feeding it, so the gap has to go somewhere: a buffer that keeps growing, or a trip back to unity. That is the structural reason most insert varispeed is a gesture rather than a setting, and why the shape and length of the journey home matters more than the depth of the dip.

It tells you where it is. Percent, semitones, or both. A knob marked 0 to 100 is guesswork, and guesswork is how you end up a quarter-tone out against a bassline you already printed.

It behaves the same at every buffer size. Set 128 samples, then 1024, and render the same move twice. If the two files do not line up, the timing is being done in blocks rather than in samples, and every bounce will be a slightly different take.

SKRUU is our varispeed pitch and time stretch plugin for Mac and Windows, with PITCH and TIME on separate knobs and sixteen shapes for the trip back to unity. There's a demo on the page.

How to test a varispeed plugin in ten minutes

Do this with the demo before you pay for anything. One loop, one pass, and it sorts the field faster than any review will.

1. Load an eight-bar loop with cymbals, a sustained pad and a vocal in it.
2. Set the rate to +10% and render. Listen to the top end on headphones for ringing or grit.
3. Set the rate to −10% and render. Listen to the tails for flutter or stepping.
4. Automate the rate from 0 to −6% over one bar and back. Listen to the turn, not the dip.
5. Render that automation at a 128-sample buffer and again at 1024, then null the two files.
6. Check the reported latency in your DAW's plugin delay compensation display.
7. Bypass at unity and null against the dry track. Anything left is coloration you did not ask for.
8. Open ten instances on ten tracks and watch the CPU meter before you put it in a template.

Step four decides it. Everybody can fall. The turn at the bottom, and the shape of the climb back, is where the cheap ones sound like a pitch bend and the good ones sound like something with mass.

Named varispeed plugins, and what each one is for

Everything below was read off the maker's own page while writing this. Where no price appears, the page would not give one up, and a wrong number is worse than no number.

GSi VariSpeed. Free, for Windows, macOS and Linux, currently version 1.0.0. GSi describe it as a simulation of a belt-drive tape echo whose capstan motor can change speed, so the speed control varies the delay time, and they state plainly that it reproduces the hardware as is, with its pros and cons and no added features beyond being digital and MIDI-controllable. If you want the tape-echo dive rather than a track transpose, start here and stop here. They ask for a donation, and they note the Linux build is experimental and ships as raw binaries you place by hand.

Kilohearts Tape Stop. Free with an account. Tape speed simulation with four controls: a Play button holding the state of the motor, Stop Time, Start Time, and a Curve for the speed ramp. It runs as an ordinary plugin and also as a Snapin inside their modular hosts. The whole point is the stop and the start, so if you wanted a rate you could park at −4%, this is not that, but as a free tape stop it is hard to argue with. Longer piece here on how to make a tape stop effect.

Cableguys TimeShaper 3. 29 €, running inside their ShaperBox 3 host, with a free trial. You draw the position of a virtual playhead inside the audio, which gets you slow-downs, speed-ups, reverses, scratches and tape stops from one control surface, synced to beats and bars. There is a separate curve for lows, mids and highs, and Cableguys say the resampling interpolation is built to keep aliasing down when you modulate speed hard. Drawing is a different way of working from riding a knob, and for beat-locked gestures it is the stronger one.

Varispeed by Elisabeth Homeland. €20,00, and a Max for Live device rather than a plugin, so it needs Live Suite or Live Standard with Max for Live; the page lists Live 11 and Live 12 on Mac and Windows. It transposes every audio and MIDI clip in both Session and Arrangement view by up to −24 or +24 semitones while changing the Set's tempo to match, and it can exclude tracks by a keyword in the track name so the drums stay where they are. This is the whole-session transpose, and it answers the Ableton half of the question.

u-he Satin. 129 €, a tape simulation for macOS, Windows and Linux with a demo download. Its relevance here is the adjustable tape speed, which runs from 1.87 to 30 ips, plus a delay mode with two or four heads. It is a tape machine first and a speed control second, so buy it for the tape and take the speed as part of the deal. The physical side of that relationship is in tape speed.

AudioThing Reels. $59, for macOS, Windows and Linux in VST2, VST3, AU, AAX and CLAP, plus iOS, with a demo. Built around a consumer reel-to-reel recorder, it includes tape start and tape stop with an adjustable speed for the effect, alongside wow and flutter, dropouts, crosstalk, hiss and motor noise. Same shape as the Kilohearts device with a whole lo-fi machine attached.

Chow Tape Model. Open source, with the source linked from the developer's own product page, for Windows, Mac, Linux and iOS, and the subject of a paper presented at the 2019 DAFx conference. Serious work on the tape itself. No transport, so no speed ride, but it belongs in any answer to "varispeed tape plugin" because it is often what people actually want when they type that.

Where varispeed goes in the chain

First, before anything that reacts to level or time. A compressor after a varispeed dip hears a quieter, longer signal and behaves correctly. A compressor before it gets its release times stretched along with everything else, which sounds like the compressor is broken.

Reverb and delay go after it too, for a better reason: a move that drags the tail down with the source sounds like a machine, while a dry source sagging into a stationary tail sounds like two recordings. A stationary tail is a real choice, but make it on purpose with a send rather than by accident with an insert order. The exception is the tape-echo case, where the varispeed lives inside the delay and the bending repeats are the whole point.

What it costs you

Varispeed commits you to a key change, and that is most of the bill. Drop a sample 6% and it is about a semitone flat of where it was, so either the arrangement follows it or you are writing around a new root. Producers have taken that trade for fifty years because the sound of the trade is the point, but it is a trade, and the alternative is on the time stretching page.

Upward moves cost top end and body. Past about +8% on a full mix, cymbals thin out and voices sound small, because you have shrunk every resonance in the recording including the ones your ear reads as size. Slowed material has the opposite problem: the noise floor comes down with everything else, and hiss slowed 20% falls nearly four semitones and stops sounding like air.

And real-time varispeed costs latency somewhere, or costs you the ability to hold the offset. You will either see the number in your DAW's delay compensation display or find that the control wants to come home. Both are honest. A plugin claiming neither is worth a close look at step five above.

Hear SKRUU

Questions people ask

What is the best varispeed plugin?

There is no single best one, because the category holds four different tools. For a whole-session transpose in Ableton Live, a Max for Live device is the right shape. For a tape-echo dive, GSi VariSpeed is free and purpose-built. For a beat-locked drawn gesture, Cableguys TimeShaper. For a continuous rate you ride and automate on an insert, you want a dedicated varispeed plugin with the rate on a knob and a designed return, which is the category SKRUU is in.

Is there a free varispeed plugin?

Yes, several, covering different jobs. GSi VariSpeed is freeware for Windows, macOS and Linux and gives you the tape-echo version. Kilohearts Tape Stop is free with an account and gives you the stop and the start with a curve on both. Both were listed at no cost on the developers' own pages when this was written. Before either of them, check your own DAW: turning warping off and transposing a clip is varispeed, and it costs nothing.

Where should you download a varispeed plugin?

From the maker's own site, every time. These searches land on aggregator pages that reprint the developer's blurb word for word and wrap it in a download button, and those pages are often years behind the current version. Read the blurb wherever you find it, then go to the developer and get the file there.

What is a varispeed tape plugin?

Usually one of two things: a tape machine simulation with a speed control, where changing speed changes pitch, tone and flutter together, or a tape echo where motor speed sets the delay time and moving it bends the repeats. Decide which one you want before you buy, because they sound nothing alike.

Why does this keep getting asked on forums?

Because the obvious answers are all slightly wrong. The DAW method is destructive and cannot be played live. Pitch shifters break the link between pitch and time that people are asking for in the first place. Tape plugins mostly model the tape rather than the transport. A continuous rate you can ride on a bus is a narrow piece of engineering, and narrow things are under-supplied.

Does varispeed work on a full mix?

Yes, and it is one of the few processes that holds together on a full mix, because everything moves by the same ratio and nothing gets out of step with anything else. That is the whole basis of slowed and reverb and of chopped and screwed.

What SKRUU does

SKRUU is our varispeed pitch and time stretch plugin for Mac and Windows, in VST3, AU and standalone, and it puts rate and length on two knobs that do not touch each other. PITCH is the varispeed control: it runs from −20% to +10% in 128 states and reads out in semitones as well as percent, with the scale printed under it so you can see −3, −2, −1 and +1 ST where they fall. TIME runs from −50% to +25% and moves nothing but the length. PITCH LOCK and TIME LOCK hold one while you play the other, so you can speed a loop up while pitching it down.

The return took the longest to get right. ELASTIC makes the knob sprung: move it, let go, and it runs home. SLOPE is the shape of that journey and there are sixteen of them, drawn on the panel with the time of the trip printed on the curve, and PITCH and TIME each get their own. DRAG sets how long a new speed takes to arrive. SAMPLING GRADE steps the rate down in four grades, from HI-FI at 31.25 kHz to LO-FI 2 at 3.91 kHz, which is the other half of what a slow machine does to a recording.

The thread will be back in a few months, phrased the same way, and somebody will say the DAW can do it. The DAW can. It just cannot do it while the track is playing and your hand is on the control.

Keep reading

• What is varispeed — Speed and pitch together: the math, how it differs from pitch shifting, and how it's used.
• Time stretching explained — How the algorithms work, which mode to use, and when to repitch instead.
• How to make slowed and reverb — Slow it with varispeed, add a long dark reverb, and make sped-up versions too.
• How to chop and screw a song — Where DJ Screw's Houston sound comes from, and how to screw and chop a song in a DAW.
• How to change pitch without changing tempo — How pitch shifting and time stretching work, which mode to use, and how to avoid artifacts.
• Best doppler plugins — Why most doppler moves sound wrong, and what a real one drives.

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