Re: Silently depressed keys

[Devon Schudy]

On Mon, May 30, 2016 at 9:53 PM, Dan Eble <address@hidden> wrote:
> Here’s something else I could use help with. The person who wrote
> Midi_note decided that a negative (“unknown”?) Audio_dynamic should
> be treated as 90/127, whereas the person who wrote Midi_dynamic
> decided that a negative Audio_dynamic should be treated as 100/127.
> Unless there is a good reason for this inconsistency, I would like
> to move the default into Audio_dynamic itself; but I’m not sure
> which value to use. Are these specific values important, or are they
> just two individuals’ fingers in the wind?

90 is from commit 54dcf612719bd5275bdf2231405be713be61fbf8 by Martin
Tarenskeen in 2009: “Note-On: velocity=127 lowered to 90 =
mezzoforte”. This is roughly right; midi.scm defines mf = .68 * 127 =
86. The instrument equalizer can change that, but it doesn't look like
any of the default ones give 90.

100 is from commit f114e3c33f9c37c39c7a3fedf66ca5a074785118 by Jan
Nieuwenhuizen in 2011: “When we are using note velocities, always
output the default midi channel value, which is 100.” I doubt 100 is a
standard default; MIDI doesn't standardize much.

So yeah, they're probably just two guesses.

> Apart from that, I think it would be a good idea to rename the music
> property midi-extra-velocity to relative-volume and change its range
> to [-1,1] to match the scale of the context property
> dynamicAbsoluteVolumeFunction instead of being MIDI-specific. Are
> there any objections?

See this thread:
https://lists.gnu.org/archive/html/lilypond-devel/2013-11/msg00260.html

I agree that extra-velocity ought to work like
dynamicAbsoluteVolumeFunction (and maybe be affected by instrument
equalizers). IIRC I didn't do it that way because dynamics and notes
are performed separately, and by the time they get combined (in
Midi_note) everything has already been converted to velocities. But
multiplying by 127 is as good as the current way, and
midi-extra-velocity is still undocumented, so changing it won't bother
many users.