by Jojon » Sat Feb 21, 2009 2:53 am
OK, pet peeve of mine, so I'll rant a bit.
MIDI is a protocol for communication between musical devices - nothing more, nothing less. It allows you to play on one keyboard and have another synthesizer produce the sound. You can record your keyboard bashing (which keys you hit, when, how hard, how hard you keep the key pressed down, when you release it, etc) in a sequencer, that can then play it back, etc. There is lots of sequencing software that talks MIDI and most of those packages have their own custom file formats.
Now, at one time somebody at Yamaha (IIRC) figured that wouldn't it be nice if there was some sort of standard set of sounds and controllers, that one could rely on being the same between different synths and a singular file format for sharing music adhering to this limited setup. Thus "General MIDI", or "GM" was created and this is what many people refer to, when they say MIDI. Some synths came out that had a GM patchbank came out.
I really wish they would have called it something else -- this is a little like Netscape's "javascript"; it has nothing to do with Java, so why on earth would they pick that name, other than to ride on the coattails of Sun's hype. In the end you've got nothing but a lot of confusion.
General MIDI was used in a lot of PC games, because soundcards started to come with GM wavetables onboard - since you don't have to distribute the actual sounds with the game, you got nice compact files, many of which fit on a floppy disk.
All GM devices does not sound quite the same, however. The standard says that sound (or "patch") number 1 is a grand piano, but does not perscribe EXACTLY how it must sound or behave, so you get different quality dynamics with different sound sources. The simple single sample based wavetables typically used in soundcards, along with the other restrictions of setting a least common denominator, has given GM and by unfair extension MIDI, a reputation for a flat, boring, dead sound.
You can do great stuff wihin the GM framwork, mind, but is should typically be recorded off the equipment used by the composer, for by now hopefully obvious resons.
Right, sorry about that intermission - on with the show. :7
