The MIDI 2.0 Protocol raises resolution on all Channel Voice Messages and adds per-note expression

The MIDI 2.0 Protocol provides extended data resolution for all Channel Voice Messages, replacing MIDI 1.0’s 7-bit (0-127) values with far higher-resolution fields — so controllers, velocity, pitch bend, and aftertouch move in finer steps with no audible quantisation. It also adds new Channel Voice Messages for increased per-note control and musical expression, meaning parameters can be addressed to an individual sounding note rather than only to a whole channel. It further tidies MIDI by aggregating some multi-message combinations into single atomic messages. This higher resolution and per-note addressing is what makes MIDI 2.0 markedly more expressive than MIDI 1.0, but it only exists in the UMP data format over MIDI 2.0-capable transports.

Examples

Pressing harder on one held key in a chord changes only that note’s timbre via per-note control, while MIDI 1.0 channel aftertouch would affect every note on the channel at once; parameter sweeps step smoothly instead of in 128 audible increments.

Assessment

What changes for a performer when Channel Voice Messages gain higher resolution and per-note control? Why can MIDI 1.0 channel aftertouch not express a single note within a held chord?