Air Theremin Online
Play a theremin online with nothing but your webcam. Right hand for pitch, left hand for volume, note snap to stay in tune, and a mouse mode for laptops without a camera.
Camera stays on your device
Frames never leave your device. Best in Chrome or Edge on a laptop; Safari and phones fall back to touch if tracking is slow. Trouble?
What a theremin is, in one paragraph
The theremin was invented by Leon Theremin in 1920 and is played without touching it: one hand near a vertical antenna controls pitch, the other near a loop controls volume. Webcam hand tracking gives you the same idea in a browser. Your right hand's position across the frame becomes pitch and your left hand's height becomes volume, so the gesture is the instrument.
Controls
- Pitch: move your right hand from the left edge (low) to the right edge (high). The range is two octaves.
- Volume: raise or lower your left hand. With only one hand in view, that hand's height sets the volume.
- Vibrato: pinch thumb and index finger together on the pitch hand.
- Note snap: on by default; pick Major, Minor, Pentatonic, Blues or Chromatic. Turn it off for a true sliding pitch.
- Sound: Warm is the closest to a classic theremin tone; Strings adds a slow attack.
- Silence: lower your volume hand, or take both hands out of the frame; the note fades within a fraction of a second.
Three tips
- Keep your pitch hand open and facing the camera. An edge-on hand is harder to track and the pitch will wobble.
- Start with the Major pentatonic scale in C: every position sounds good, which makes the hand-to-pitch feel easier to learn.
- Turn on the beat at 70 BPM and play long notes across the bar before trying melodies.
For a comparison with other browser theremins, including the Air Theremin that reached the Hacker News front page, see the air theremin page in the instruments hub. If the camera or sound does not start, the troubleshooting guide has fixes for each symptom. Prefer chords? Go back to the gesture synth.
FAQ
Questions
- How do I play the online theremin?
- Press Begin, allow the camera, and move your right hand left and right across the frame for pitch. Raise your left hand for volume. With one hand, its height sets the volume. Pinch your thumb and index finger together for vibrato.
- Can I play it without a webcam?
- Yes. Choose Mouse / touch as the input and drag across the stage: left to right is pitch, up is louder. On the keyboard the A to L row plays scale notes.
- Why does it sound out of tune?
- A real theremin has no frets, and that is the hard part. Leave Note snap on to land on the notes of the chosen scale, or turn it off for pure continuous pitch.
- Which range does it cover?
- Two octaves starting near the key's tonic below middle C. Choose the key and scale in the controls; the readout shows the note name and frequency in hertz.
- Does it send MIDI?
- Yes, in Chrome or Edge on desktop. The theremin sends note-on for the current note, pitch bend for the distance between notes, and CC1 for volume.