Mike,

First, welcome back to the music world and to the forum. I'd like to answer your question about general midi.

Background:
Look at a photograph of the keyboard player of the late seventies to mid eighties and you likely saw one or more racks of keyboards and sound modules. Each device likely could generate only one to six notes at a time and generate the sound of one instrument. Voltage signals were used to activate and synchronize the different devices but every manufacture developed their own system to tie equipment together. Midi was developed to standardize both a hardware interface and the commands needed for equipment developed by multiple companies to play together.

Soon after the midi standard was released another problem was recognized. When a standard midi file (SMF) or (MID) is played, how do you get the guitar track to sound like a guitar on all equipment? The midi standard was updated to include a list of 128 instruments or sound effects. This is called general midi or just GM for short. The list assigns a midi number to each of the 128 instrument patches. That way a guitar is a guitar as long as a guitar instrument patch number is assigned to the track that has the guitar notes and chords.

One-up being the nature of business the keyboard manufactures expanded the GM list to include additional instruments and soon midi files were developed to play XG or GS midi files in addition to GM files. The midi organization responded with an expanded instrument list called GM2 that includes midi commands to make instrument bank changes.

At the same time keyboard and sound module hardware was developed to play more notes at the same time and to play more instruments at the same time. Thus one keyboard or sound module can replace multiple pieces of hardware.

So a soft synth, hardware sound module like the Ketron SD2, or keyboard can adhere to one or more standard or the manufacture can develop their own standard.

Jim Fogle - 2025 BiaB (Build 1128) RB (Build 5) - Ultra+ PAK
DAWs: Cakewalk Sonar - Standalone: Zoom MRS-8
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