Polyphonic synthesizer. Audio stays silent until you start it. Play the on-screen keys or the computer keys A through apostrophe. Z, X, and the arrow keys shift the octave.

Northline

Desk synthesizer

Audio off

Start or play a key

OscilloscopeLevel

Waveform

Octave

C4–C5

4
Volume80%

Filter

Cutoff2.2 kHz
Reso0.8

Envelope

Attack20 ms
Decay180 ms
Sustain72%
Release280 ms

Play the labeled keys. Z, X, or the arrow keys shift the octave.