Metal bars, left to ring.
The notes are recordings of a real vibraphone, metal bars struck with the pedal held down so each one rings for seconds, three octaves from the C below middle C. It is the marimba's metal cousin, and the sound of cool jazz.

Real vibraphone metal bars, struck with the pedal down so every note rings.
No MIDI keyboard? Play with your computer keys: bottom rows are the lower octave, top rows the higher one. Hold Shift to sustain. ← → octave, ↑ ↓ semitone.
Online vibraphone
The notes are recordings of a real vibraphone, metal bars struck with the pedal held down so each one rings for seconds, three octaves from the C below middle C. It is the marimba's metal cousin, and the sound of cool jazz.
Plug in a controller and play jazz chords with both hands: hold the keys and the bars ring together. Lift a key and that bar is damped, like the pedal coming up.
No download, no account and no sign-up. The vibes are played by your own browser, on your own computer.