Timpani and Tabla

The head of the last drum struck, from above, in slow motion: warm where it bulges up, cool where it dips, each mode at its own pace. The dot is where the beater lands, the ring the resting finger, the cross the heel; the dark disc is the tabla's syahi. Struck near the rim the head breaks into many sectors, the (m,1) modes; struck at the centre only the round ones move.

Each mode's frequency over the note (solid, its length how loudly the listener hears it), against a bare head in a vacuum, no air and no syahi, tuned to the same note (hollow), and the harmonics of the note (grey lines). The air and the syahi pull the modes onto the harmonics.

The round modes, which push air in and out like a piston, radiate fast and die first: the timpani's thud. The (m,1) modes ring on as the note. Press the bayan (aftertouch) and watch every line bend up together.