Online instrument · No account needed
Online synthesizer
Play a responsive three-octave synth, start from 21 presets or randomize a safe patch, then shape every stage of the sound and record the result locally.
How do you use this online synthesizer?
Press a piano key or its displayed computer shortcut. Start with a preset, then change one module at a time so you can hear what each control does.
- Choose a preset or Random sound to create an audible starting point.
- Hold several keys together to play chords, then adjust oscillator, filter and envelope controls.
- Record up to five minutes, listen back, and download the browser's supported audio file.
What changes the synthesizer sound?
The signal starts with two pitched oscillators and an optional noise source. A low-pass filter changes brightness, the ADSR envelope shapes each note over time, and effects add space and movement.
Can you play it with a computer keyboard?
Yes. The 36 mapped keys cover C3 through B5 and support several held notes at once. Turn shortcut labels off in Settings when you no longer need them.
Touch and pointer input use independent owners, so chords work on compatible phones and tablets too.
Where does a synthesizer recording go?
The master output is recorded inside your browser. ClefPulse does not request microphone access and does not upload this recording.
The file format depends on what your browser can encode reliably. A recording stops automatically at five minutes.
Questions about the online synthesizer
Can the synthesizer play chords?
Yes. Pointer, touch and mapped computer-key inputs can hold multiple independently owned notes. The runtime limits active voices to keep sound responsive.
Does the synthesizer work on a phone or tablet?
Yes. The keybed pans horizontally on narrow screens, controls keep touch-sized targets, and landscape mode keeps the keyboard ahead of the horizontally scrollable sound modules.
Does recording use my microphone?
No. Recording captures only the synthesizer's own master output. It stays in browser memory until you download it, replace it or leave the route.
Can Random sound create silence or unsafe feedback?
No. Random patches use bounded source levels, keep at least one audible oscillator, and limit filter and effect values to safe operating ranges.
How is the browser audio implemented?
ClefPulse uses the browser's standard Web Audio graph for synthesis and its recording interface for local capture. The links below document those platform contracts.
Technical references reviewed on .
- MDN: OscillatorNode
Reference for periodic waveform generation and pitch control.
- MDN: AudioParam
Reference for time-scheduled audio parameters used by envelopes and control changes.
- MDN: MediaRecorder
Reference for browser-supported encoded capture from a media stream.