Number: 7 (coarse) 39 (fine)
The volume level for one MIDI channel. If a MultiTimbral device, then each Part has its own volume.
Note: A device's master volume may be controlled by another method such as the Univeral SysEx Master Volume message, or take its volume from one of the Parts, or be controlled by a General Purpose Slider controller.
Expression Controller also may affect the volume.
14-bit coarse/fine resolution. 0x0000 to 0x3FFF where 0 is no volume at all.
Note: Most all devices ignore the Fine adjust (#39) for Volume, and just implement Coarse adjust (#7) because 14-bit resolution isn't needed for this. In this case, maximum is 127 and off is 0.
It is recommended that a device use the volume value in a logarithmic manner, as specified by the following formula if only the coarse value is used:
40 log (Volume/127)
If both the coarse and fine values are used (and combined into a 14-bit volume), then use the following formula:
40 log (Volume/127²)
Note: In the above formula, "Volume" may be equal to Channel Volume * Expression.