How do you synthesize/analyze audio on the waveform level with HTML5? AFAIK this is only possible with an alpha version of Firefox implementing an experimental API, not part of HTML5. Flash can do full waveform synthesis as of v10, audiotool wouldn't work without it. The only way I can imagine doing this is creating data: URI's for <audio> in Javascript containing raw OGG/WAV data, which is write-only, half-baked and seems impractical.