Sorry, but I don't think there IS such a midi command. In the terms that you seem to be suggesting.

You can apply global midi commands to chance Tempo, Time Signature, Key, but not tuning.

Many of the devices (keyboards, modules, etc) that allow the precise sound/patch to be edited, include a parameter for tuning or transpose, which will affect that specific sound ONLY. Such a modification may well be appropriate to that sound. A global adjustment however could well be trying to change instruments/sounds for which it is NOT appropriate.

Furthermore, midi works because note number ## is defined as being note ff (frequency). If you adjust the global tuning of the device, and then play a midi file, the sound could now be wrong?

Geoff

Actually...

Just had a dig into the manual of my Yamaha MU90r, and I see that there IS such a facility, BUT...

It's within the section called 'Multi Part Edit', and the Roland device may or may not have some thing similar. The specific section is called Transpose, and will affect ALL Parts. The setting is made in semitone increments with the range of -24 to +24 from default. This may not be fine enough for OP's purpose?

The facility is available from the front panel on the unit, and is NOT available directly from midi, although it should be possible to create a SYSEX instruction to write the required numbers to the correct memory addresses, but you'd need to do a fair bit of digging in the manual. And the details of the command will be different between various devices.

Of course, the Roland device could be quite different!

Geoff