A jambati is the large, deep walled bowl of the Kathmandu Valley, raised from a bronze disc by four or five smiths hammering in rotation while the metal is hot. The dents you can see across the belly are where their hammers landed. Bowls like this were household grain and curd bowls long before anyone sold them as instruments.
The look
Nothing here is a photograph. The bowl is a lathed profile turned in three dimensions, and its bronze is a texture built in code: colour, hammer relief, roughness and patina, lit against an environment map that is itself drawn from gradients. The mandala inside the base is engraved procedurally, with the seven chakra medallions and their seed syllables in Devanagari.
The sound
No recordings either. A struck bowl is not harmonic like a string. Its partials sit at roughly 1, 2.7, 5.4, 8.9 and 13.3 times the fundamental, and each one is really a pair of modes a fraction apart, which is where the slow warble comes from. Every partial is synthesised as a detuned pair with its own decay, so the high metallic edge dies away in a second or two and the fundamental keeps going.
Rubbing the rim is a different mechanism: the mallet grips and slips hundreds of times a second, feeding energy into the same modes until they sing. That is why the tone here builds over a few seconds instead of arriving at once, and why it fades when you stop moving.
The frequency
You set the fundamental exactly, from 60 to 800 hertz. Real bowls cannot be retuned like this, so the bowl on screen changes size as you move the rail, the way a heavier, wider bowl really does sound lower.
The tuning sets on offer, planetary, solfeggio and chakra, come from twentieth century esoteric traditions rather than from clinical medicine. People find them calming and meaningful, and that is a real effect worth having. They are not treatment for illness.
Opening it at a set pitch
Add ?frequency=144.25 to the address and the bowl opens there. ?autoplay=1 turns the opening button into one that begins a session. ?length, ?every, ?pace, ?journey, ?voices, ?mallet, ?speaker and ?volume set the rest, so a particular practice can live in a bookmark.
Playing itself
A sound bath is one person circling a rim for half an hour. The session does that circling for you: the same rubbing and striking a hand does, driven by a breath instead of a wrist. The sung tone swells and falls with the pace you set, struck notes land on the turn of the breath rather than on a metronome, and the speed of the mallet wanders slightly so it never settles into a machine. A journey walks the tuning up through the seven centres, or down from the crown, holding each for as long as you like. Sessions fade out on their own rather than stopping.
The long exhale pattern, four counts in and eight out, is the one with the most evidence behind it: a slow out breath lengthens the parasympathetic response. The rest is a matter of what you find comfortable.
Playing it yourself
Tap the belly to strike. Drag around the rim, slowly and steadily, to make it sing, and keep going once the note appears. Drag the background to look around the bowl. Space strikes, and the arrow keys move the tuning.