[fluid-dev] Re: MIDI mode

[jimmy]

I think GM support is all I can ask for, but understand how GS, XG are designed 
and know how to scale them back to GM level is all Fluidsynth need to do.

About MIDI mode of GM, GS, XG...  I don't have any official reference, but from 
what I understand, GM only has 128 defined instrument list, and maybe a few 
drumsets.  That can get old after a while.

The many hardware makers of "MIDI modules", MIDI capable "synth keyboards", and 
"arranger keyboards" need to add better sounds on their higher priced jewels.  
So they decide to keep the basic GM common between one price-level to the next 
by adding better sounds and drumsets as extensions (extra sounds in extra 
banks, still keeping the familiar 128 instruments GM definition loaded with 
relatively cheaper sounds).  Some may just be the exact sound samples with 
different special effect settings (panning, reverb, cutoffs...)

For example they can have 4 different nylon guitar (or Sax, Strings...) sounds 
on the same program number, but on different banks, even if there are few or no 
other voices on these extra banks.  They would have different "demos", or 
"songs", or "rhythms" using those different nylon guitars that sound much 
better than the cheaper hardwares they have.  The cheaper hardware when trying 
to play those nylon guitar instruments won't have those instruments in the 
defined banks (via MIDI cables, or MIDI files), will fallback to use the same 
program number on bank #0 (GM instrument).

Likewise, SYSEX's are hardware specific, mostly depends on what sound chips and 
what type and how many special effects (DSP) chips are on that box.  If a 
hardware sound module/keyboard doesn't know how to handle some SYSEX messages, 
it simply ignores those SYSEX's.  Even the higher end Yamaha keyboards won't 
work with SYSEX's from cheaper Yamaha keyboards, and vice versa.  Because they 
have different hardware engines (firmwares and chips...)  I know of no hardware 
boxes that claims to support all the SYSEX's out there, each will only handle 
its own particular SYSEX's to control it's own specific hardware model.

That's also how GS and XG claims that they are extensions of GM and all the 
hardware MIDI playing (via cable connection, or MIDI files) can still render 
appropriate sound, of course, "appropriate sound" may only match the type of 
instrument voice (i.e. Strings, Nylon Guitar, Oboe, French Horn, Sax...) and 
may not sound at all as good as it is intended for the hardware it was tweaked 
for.

So as long as Fluidsynth provide the appropriate "fallback" instrument-voice 
look up and all the basic GM features, Fluidsynth is at least as good as any GM 
hardware modules out there.  In fact a GM-supported Fluidsynth allowing 
changing of soundfont would be better than all the GM hardwares that won't 
allow changing (customizing) of their instrument voices.

I think GM support would be great...  However Fluidsynth interpretes the GM 
specs, all hardware makers out there does the same anyway.  After that, GM2 
might be something to look forward to.  Since Yamaha already snuffed out XG 
(removed all references to XG softwares and XG specs), and Roland doesn't seem 
to get any better brainshare with GS.  Those existing MIDI files out there 
still only sound best on the hardware they were created on, Fluidsynth only 
need to sound the appropriate voices as the notes are played.  The rest depends 
on having a superb GM soundfont and maybe a few special soundfonts on top of GM 
sounds.

Jimmy