redbarchetta said:
Which is basically what I said. I didn't realize compression was involved though; I thought it was due to the GBA's chip being incapable of reproducing those sounds in a real-time environment, thus the songs were simplified. Plus we're dealing with Midis, not MP3s, why would they be compressed?
Argh.
Think of it this way - what is MIDI? It's a series of notes. Thats it. It's like a notepad document - no sound is generated by the MIDI file, it simply tells the soundcard what to play and when.
The SPC format and the GBA sound format work similar to this - all the notation is stored as hex in the ROM, and then the game calls on it - when this happens in the SNES, the SPC700 reads this information and then loads sound samples in the ROM for the instruments. The SPC700 was very versatile in terms of sample size and channels (8 of them).
With the GBA, there was no dedicated sound chip. Therefore, all the tasks the SPC700 would do on the SNES had to be handled through the GBA's processor and ram - which were limited to say the least as well as being used for the game at the same time. The GBA was not able to handle the higher quality instrument/sound samples that the SNES would, so instrument/sound samples had to be compressed horribly (as in the independent WAV/RAW files, not the entire track). When the GBA sequences a track together, it uses these much lower quality sound samples and the result is a lower quality audio track.
Understand a bit better now?