Rewrite noise handling code to avoid manual buffer stretching in most situations. Instead, return a buffer source node that will loop one second of noise. This also removes the need for the length check hack in scheduling, and allows an onended handler for disconnection.
Change Instrument API to take an absolute time, not an offset, but special-case 0 to mean now.
Shorten FM bell instrument.
Integrate sample playback into Instrument, including playback rate modulation and filters. Rewrite filter generation so it always terminates at the final gain node.
More work on magic circle animations.
Start of some full instrumental track handling.