Compressor Attack & Release Settings

Attack and release are the two timing knobs on a compressor, and getting compressor attack and release settings right is what decides whether compression adds punch or quietly kills it. You can hear the difference in seconds with the free in-browser compressor: attack is how fast the compressor clamps down once your signal crosses the threshold, and release is how fast it lets go once the signal falls back below. Threshold and ratio decide how much the compressor grabs. Attack and release decide what it feels like.

Most bad compression isn't caused by too much gain reduction. It's caused by the wrong attack and release for the material. This explainer walks through what each control does, how they work together, and honest starting points by instrument. It's the theory companion to the step-by-step compressor walkthrough — if you want the click-by-click, start there and come back for the why.

What attack time does

Attack time is measured in milliseconds and controls how quickly the compressor reacts after your signal passes the threshold. A fast attack (roughly 0.1–5 ms) clamps down almost as soon as the sound arrives. A slow attack (20–100 ms and up) lets the first slice of the sound through untouched, then starts compressing the body behind it.

That first slice matters more than you'd think. The sharp, loud spike at the very front of a note — the pick hitting a string, the stick hitting a drum, the consonant at the start of a word — is called a transient. Transients are what your ear reads as punch and attack and clarity. They're short, but they carry a huge amount of the character.

Here's the part that trips people up. A fast attack catches the transient and squashes it, so you get a rounder, tamer, more controlled sound — but you can lose the snap. A slow attack lets the transient pass before the compressor grabs the sustaining body of the note, so the punch stays intact and often sounds bigger, because the loud front is now sitting well above the compressed tail.

So the counterintuitive rule: if a track sounds dull or lifeless after compression, your attack is probably too fast. If it sounds spiky and out of control, your attack is too slow. Neither is "correct" on its own — it depends entirely on what you want the sound to do.

What release time does

Release time controls how fast the compressor stops reducing gain once the signal drops back below the threshold. It's also in milliseconds, though it usually runs longer than attack — anywhere from ~50 ms to several hundred.

Release is where compression either disappears or announces itself. Set it too fast on a sustained sound and the compressor keeps releasing and re-clamping in rhythm with the audio, which you hear as a distracting wobble in the level. On a whole mix or a synth pad this is called pumping or breathing — the background seems to rise and fall, or "breathe," in time with the loud hits. A little of this is a groove effect some producers chase on purpose. A lot of it is just a mistake.

Set the release too slow and the opposite problem appears: the compressor never fully recovers between notes. Each new hit lands while the compressor is still holding down gain from the last one, so quiet passages get dragged down and the track loses life and dynamics. On fast material — busy drums, rapid vocals — a too-slow release can flatten everything into a lump.

The sweet spot is a release that recovers between the events you care about. On a vocal, that means letting go between words and phrases. On a drum bus, it means recovering between hits so the groove keeps breathing without pumping. When release and tempo line up, compression turns into glue — a smooth, cohesive feel that makes separate elements sound like they belong together.

How attack and release work together

Attack and release aren't independent dials — they shape the same envelope from opposite ends, and they only make sense in the context of your threshold and ratio.

Think of it as a sequence. Threshold sets the line the signal has to cross. Ratio sets how hard the compressor pushes down once it's crossed. Attack sets how fast that push arrives. Release sets how fast it backs off. Change the threshold and you change how often attack and release even fire; a threshold so high nothing crosses it means your timing knobs do nothing at all.

A practical way to dial them in: set your threshold and ratio first so you're seeing a sensible amount of gain reduction (the meter reading of how many decibels the compressor is pulling down — 3 to 6 dB on peaks is a reasonable starting range for most sources). Only then tune attack and release by ear, because their effect is only audible once the compressor is actually working.

If you want more control than a compressor gives you on peaks — a true ceiling that nothing crosses, rather than a ratio and a slope — that's a different tool. See compressor vs limiter and what is a limiter for where one ends and the other begins.

Attack and release settings by material

There's no universal setting, but there are reliable starting points. Every range below is a place to begin, then adjust by ear. Vocals and full mixes map neatly onto two of the tool's built-in presets, noted where they apply.

Vocals — Attack ~3–10 ms, release ~150–300 ms. Vocals need control without sounding squashed. A medium-fast attack tames the loud consonants and evens out the performance; a release in the 200 ms region lets go between words so the delivery still breathes. The tool's Vocal preset starts you at attack 3 ms, release 250 ms (threshold -24 dB, ratio 3:1, +4 dB makeup) — a solid all-purpose vocal starting point.

Kick and snare — Attack ~10–30 ms, release ~100–200 ms. Drums live and die by their transients, so a slower attack here is usually your friend: let the initial hit crack through, then compress the body for weight and sustain. Too fast and you flatten the very snap that makes a drum hit.

Drum bus (whole kit) — Attack ~10–30 ms, release ~100–250 ms, aiming for gentle gain reduction. This is glue territory. You want the kit to feel like one instrument, not to crush any single hit. Time the release to the tempo so the room recovers between beats and you get cohesion without pumping.

Bass — Attack ~10–40 ms, release ~100–200 ms. Bass is mostly sustained energy, so a medium attack preserves the pluck while a moderate release keeps the low end steady and even. Fast, consistent compression on bass helps it sit reliably under everything else.

Acoustic guitar — Attack ~10–30 ms, release ~150–300 ms. Preserve the pick attack with a slower attack, then use a moderate release to smooth out the natural volume swings of strumming without dulling the sparkle.

Full mix / master bus — Attack ~10–30 ms, release ~100–250 ms, and only 1–3 dB of gain reduction. On a full mix you're after cohesion and a touch of loudness, never obvious squashing. The tool's Master preset starts at attack 10 ms, release 250 ms (threshold -18 dB, ratio 2:1, +2 dB makeup) — gentle by design. Bus compression is one link in a larger chain; see the mastering chain for how it fits alongside EQ and limiting.

The tool also ships an Aggressive preset (attack 1 ms, release 100 ms, ratio 12:1) for when you want obvious, heavy compression as an effect — a good way to hear what a fast attack and hard ratio actually do to a transient.

Common mistakes

Killing all the punch with a too-fast attack. This is the most common one. A super-fast attack on drums or an acoustic guitar clamps the transient flat and leaves you wondering why the track sounds dead. If compression drains the life out of a source, slow the attack down first.

Pumping from a too-fast release. If the whole track seems to breathe or wobble in time with the loud hits, your release is snapping back too quickly. Lengthen it until the movement smooths out — or, on a mix, until the pumping becomes inaudible.

Reaching for auto-release without understanding it. Auto or program-dependent release can be a fine safety net, but it hides what's happening. While you're learning, set release manually so you can actually hear how the timing changes the sound. You can't develop an ear for a control you never touch.

Chasing gain-reduction numbers instead of listening. A meter reading 6 dB of reduction tells you nothing about whether it sounds good. Two settings can pull down the same amount and feel completely different depending on attack and release. Set a rough amount of reduction with threshold and ratio, then trust your ears for the timing. Use the tool's live preview — play the file and hear each change as you make it. If a mix already sounds cluttered before you compress, compression won't fix it; see why your mix sounds muddy first.

A note on the release behavior

The in-browser compressor is built on the Web Audio DynamicsCompressorNode, which has a smooth, gentle release character rather than the hardware-style modeling of a dedicated bus-compressor plugin. In practice that's forgiving — it's harder to make it pump harshly — but it also means you shouldn't expect the razor-sharp, snappy release you'd get from that kind of dedicated plugin. Set your release a touch shorter than you might elsewhere and judge it by ear. It's honest, clean gain reduction, and for evening out vocals, taming a bass, or gluing a mix, it does the job well.

Everything runs locally in your browser. There's no account, no upload, and no limit on how many files you run, and your audio never leaves your device — the processing happens on your own machine and the export is lossless. Browse the rest of the audio explainers when you want to go deeper on any of this.

Frequently asked questions

What is a good attack and release setting for vocals?

A medium-fast attack around 3–10 ms with a release of roughly 150–300 ms is a reliable starting point. The attack tames loud consonants without flattening the performance, and the release lets go between words so the vocal still breathes. The tool's Vocal preset (attack 3 ms, release 250 ms) is built around exactly this range — start there and adjust by ear.

Why does my compression sound like it's pumping?

Pumping — that audible rise and fall of the background level in time with loud hits — is almost always a release that's set too fast. The compressor recovers and re-clamps in rhythm with the audio, making it "breathe" audibly. Lengthen the release time until the movement smooths out. A too-low threshold that keeps the compressor working constantly can make it worse, so check that too.

Should I use a fast or slow attack?

It depends on whether you want to keep the punch or tame it. A slow attack lets the transient — the sharp front of a note or drum hit — pass through before compressing, which preserves and often enhances punch. A fast attack catches that transient and rounds it off for a smoother, more controlled sound. If a track sounds dull after compression, your attack is likely too fast.

What does release time actually do?

Release controls how fast the compressor stops reducing gain once the signal drops back below the threshold. Too fast and you get pumping on sustained material; too slow and the compressor never recovers between notes, dragging down quiet passages and flattening dynamics. The goal is a release that recovers between the events you care about — between words on a vocal, between hits on drums.

Does attack time work the same on every instrument?

The mechanism is identical, but the right value changes with the material because different sources have different transients. Drums and plucked instruments have sharp, important transients, so they usually want a slower attack to preserve the snap. Sustained sources like bass or pads are more forgiving and often want a faster, steadier attack. Match the timing to what the sound needs, not to a fixed number.

How much gain reduction should I aim for?

For most sources, 3–6 dB of gain reduction on the peaks is a sensible starting range, and a full mix or master bus wants even less — just 1–3 dB. But the number is only a guide. Set a rough amount with threshold and ratio, then tune attack and release by ear, because two settings that pull down the same amount can sound completely different.