PlasticSynth is a small, growing workshop of playable, retro-flavoured musical instruments that run entirely in a web browser. There is nothing to install and no account to make — you open a page, press a key, and sound comes out. Every instrument is a little cream-plastic machine built on the Web Audio API, synthesising its voice in real time rather than streaming audio from a server.
Why it exists
Most music software wants you to download it, log in, or pay before you can make a single sound. PlasticSynth is the opposite: a link you can open on a phone or a laptop and immediately play. It is a love letter to the cheap, charming home keyboards and drum machines of the 1980s — the kind with a handful of buttons, a tinny speaker and far more character than they had any right to — rebuilt with modern browser audio so they cost nothing and reach everyone.
The collection
There are 17 instruments so far, each on its own page. They share a visual language and a sound world, but each one explores a different way to play:
- PS-10 Keyboard — A synth-plus-real-piano voice, a rhythm box and one-key-play.
- PS-20 Ribbon — A continuous-pitch strip — no frets, no keys, just glide.
- PS-16 Drum Grid — A six-voice, sixteen-step drum machine you paint by hand.
- PS-ORB Orbit — Eight notes circle at different speeds and chime as they cross the line.
- PS-CHD Strum — Pick a chord with one finger, swipe eight strings with another.
- PS-GRN Grain — A granular sampler — freeze a moment of sound and stretch it into weather.
- PS-SMP Snip — A pitched sampler — snip two seconds of anything and play it on a grid.
- PS-AER Theremin — A webcam theremin you play with your hands in the air.
- PS-SEQ Sequencer — Program a melody once in scale degrees, then play it through any voice — lead, FM, drawn wave, koto or mallets.
- PS-BAS Bass — A 16-step bass line with slide and accent — switch between a squelchy 303 acid voice and a deep 808 sub.
- PS-PRG Progression — A chord-progression sequencer in roman numerals — the harmonic backbone.
- PS-EUC Euclid — A euclidean rhythm box — spread the pulses, let the polymeter breathe.
- PS-ARP Cascade — A diatonic auto-arpeggiator — pick a chord, the arp supplies the motion.
- PS-LIF Bloom — A Game-of-Life sequencer — a colony of notes that evolves as it plays.
- PS-PAD Pad — A lush pad that swells and drifts through chords in your key.
- PS-ORG Organ — A drawbar organ that comps a chord — with Leslie, percussion and drive.
- PS-VOX Voice — A voice transformer — record a phrase, then pitch, robotise and warp it live.
The Studio
The Studio is where the collection becomes a band. Every instrument can be a track — a drum grid for the beat, keys for a bassline, an organ comping chords, a granular texture, even a voice you recorded — all sharing one clock and one tempo, so they lock together the moment you press PLAY. A global KEY keeps everything in tune, the magic DICE rolls a fresh coherent groove, and AUTO-EVOLVE quietly keeps a track re-arranging itself, hands-free. Bounce the result to a WAV or a MIDI file whenever you like.
Ways to make music — even if you don't read a note
You never have to start from a blank page:
- The generator builds a whole in-key track from a genre — or from a mood you describe in plain words.
- Type-a-tune turns any words into a melody that always stays in key.
- Renditions play famous public-domain pieces — Für Elise, Canon in D — in the PlasticSynth voice.
- Listen & jam reads the key and tempo of music playing near you and spins up a track to play along with it.
Learn as you play
A whole Academy explains how synthesis works, with a playable demo on every page; the plain-English Basicsguide covers music itself — notes, sharps, keys — for people who've never read a score; and the glossary defines every knob and bit of jargon. The instruments share one control language, too: real rotary knobs and a live oscilloscope or spectrum on each, so you can watch the sound as you shape it.
How it's built
Everything runs client-side. Synthesis happens in your browser in real time; no audio, and no camera image, is ever uploaded to or recorded on a server. The webcam theremin, the microphone sampler, the voice transformer and the listen-and-jam feature all process their input live on your device and throw it away — see the privacy page for the details.
Who makes it & getting in touch
PlasticSynth is an independent project, established in 2026, made by one person for the love of it — no server doing the work, no account, nothing to install. Found a bug, have an idea for an instrument, or just want to say hello? The contact page has the inbox. To see how it all grew, the changelog tells the whole story; to just make some noise, the guide gets you started.