Is the reverb effect a pre-recorded audio file?

No — it's a synthetic impulse response generated on the fly, random noise shaped by an exponential decay curve, and fed through a ConvolverNode, so no audio asset is downloaded for the reverb to work.

Why does the sampler change pitch when I play different keys?

It plays your uploaded sample at different playback rates relative to the root note you set — a key above the root speeds the sample up and raises its pitch, a key below slows it down, the same trick hardware samplers use.

🎹 Real polyphonic subtractive synth — not a toy

Web Synthesizer

A genuine two-oscillator subtractive synth in your browser: resonant filter, dual ADSR envelopes, LFO, glide, effects, and a sampler mode for your own recordings. Play it with the on-screen keys, your computer keyboard, or a real MIDI controller. Save patches as files. Nothing is uploaded.

Browsers require a click before making sound.

Oscillators

OSC 1 wave

OSC 1 octave 0

OSC 2 wave

OSC 2 octave 0

OSC 2 detune -8c

OSC 1↔2 mix 0.5

Sub osc level 0

Noise level 0

Amp envelope

Attack 0.01s

Decay 0.15s

Sustain 0.7

Release 0.3s

Filter envelope

Attack 0.01s

Decay 0.25s

Sustain 0.3

Release 0.4s

LFO

Wave

Target

Rate 5Hz

Depth 0.3

Effects

Drive 0

Delay time 0.3s

Delay feedback 0.25

Delay mix 0

Reverb mix 0.15

Master

Volume 0.6

Glide time 0.08s

MIDI: checking…

Octave: 4

Computer keyboard: Z–M and Q–U play notes, like a piano roll.

How it works

Every sound is built live from Web Audio API nodes — two detunable OscillatorNodes plus optional sub-oscillator and noise feed a resonant BiquadFilterNode, separate amp and filter envelopes are drawn with scheduled gain and frequency ramps, and a WaveShaperNode, feedback DelayNode, and ConvolverNode (fed a synthetically generated impulse response) provide drive, delay, and reverb — all without loading a single audio sample, unless you switch to Sampler mode and load your own.

FAQ

Is the reverb effect a pre-recorded audio file?: No — it's a synthetic impulse response generated on the fly, random noise shaped by an exponential decay curve, and fed through a ConvolverNode, so no audio asset is downloaded for the reverb to work.
Why does the sampler change pitch when I play different keys?: It plays your uploaded sample at different playback rates relative to the root note you set — a key above the root speeds the sample up and raises its pitch, a key below slows it down, the same trick hardware samplers use.

Free, unlimited, no account. If this saved you a paid tool, a small thanks is appreciated.

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