Support for smaller ".sf3" files?

[MengLinMaker]

Motivation:

• Default samples are very large by web standards. 1mb is already quite large - over 20mb for electric piano sample.
• Large files download slowly on slow networks, leading to poor user experience - 8mbps equates to over 20 seconds download time, excluding latency.
• Large files lead to high egress cost.
• Alternatively .sf2 uses uncompressed WAV samples, which are also large.

Proposal:

Support SoundFont3 which is essentially SoundFont2 with OGG VORBIS compression for 10-20x smaller SoundFont files.

I've started work on a "SoundFont2" fork which appears to be unmaintained:
https://github.com/musidi-org/soundfont3

Challenges:

Decoding OGG to WAV is not supported through AudioContext.decodeAudioData() on Safari.

SoundFont3 does not follow the SoundFont2.04 spec closely:

• Lack of EOP, EOI, EOS ending reports for presets, instruments and samples respectively.
• Sample data bytes are not even - breaking compliance with the RIFF file spec.

So far I've added the ability to parse both sf2 and sf3 files, including audio format conversion using ffmpeg, so this only works on Node.

I think it should be possible to convert sf3 to sf2 by converting OGG to WAV through AudioContext.decodeAudio()