The only thing standard in GM are the patch numbers.

The 127 continuous controllers are the same on all synths, GM or not, they are part of the Standard MIDI File set. Whether a particular synth responds to all 127 CC's depends on the synth maker. And there are GM and non-GM synths that don't support them all.

And yes, GM synths don't have every sound known to the synth world, but neither do no-GM synths. But GM synths do include the standard 127 voice GM set.

And no, all GM synths are not restricted to one sound for each of those 127 instruments. My SD 90 has a minimum of 4 variations and up to 20 variations of the same sound simply by adding a MSB and LSB into either the patch selector or entering them with CCs.

My XV5050 has thousands of sounds and it included a GM bank. Same for my SD90. My Ketron has 4 banks, one of which is GMIDI - so please don't be spreading the misconception that GMIDI synths are limited to GM sounds. There are plenty of synths that do not have a GMIDI bank that have thousands of fewer sounds than my XV.

There are good sounding synths with a GM bank and lame sounding synths with a GM bank. There are also good sounding synths without a GM band and bad sounding synths without a GM bank.

All GM specifies are common patch numbers for 127 patches - or twice that for GM2. Everything else is covered by the Standard MIDI File specs, and both GM and non-GM synths either include or don't include everything in the specs.

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Bob "Notes" Norton smile Norton Music
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