[sdiy] MIDI volume to volts formula

[Ben Bradley]

> I just need to know this: Is the "correct" response an accelerating or decelerating curve when plotting velocity on the horizontal axis and voltage on the vertical axis?  There seems to be common agreement that it's personal preference.

Of those two, I'd go with the accelerating curve (starts out flat,
gets steep toward the right end). This will make the log of voltage a
roughly linear function (and proportional to dB and perceived volume)
of the horizontal axis, and should give a good volume change over the
whole range of velocities.

On the other hand, I think a piano is a roughly linear function of
input velocity (or force) and "signal" output. This may require
"original research."