The resolution problem
Most of you will understand the problems of using MIDI to control parameters like amplitude and filter sweeps, where one wants a smooth response over a wide range. Standard MIDI data is limited to 7 bits, representing only 128 steps. This is not enough. You can sometimes hear the "staircase" effect as values switch.
This fact was recognised in 1983. That's why Pitch Bend Change is a special MIDI instruction. It uses two MIDI bytes combined as 14 bits, resulting in 16,384 steps. This "high resolution" MIDI ca nbe implemented in two ways: dual CC pairs or NRPN messages.
I am compiling a list of high-resolution hardware controllers that provide rotary encoders and switches (faders optional). On the one side are expensive control surfaces (eg. Mixed Logic M24) and also DJ tools (Torq Xponent, Vestax VCI-300, Numark NS). But these are not suitable for synthesis and creative music-making, which is my focus.
I would appreciate if anyone can adding to these lists
(This is part of my current research. I am going to cross-post this to some other places too.)