[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
RE: Quarter-tone MIDI
From: |
Nigel Warner |
Subject: |
RE: Quarter-tone MIDI |
Date: |
Thu, 30 Oct 2003 11:10:51 -0000 |
-----Original Message-----
From: address@hidden
[mailto:address@hidden
Behalf Of Morteza Dehghani
Sent: 30 October 2003 07:19
To: address@hidden
Subject: Quarter-tone MIDI
>It appears to me that quarter-tone notes are not converted to the right
>frequency in the midi format of the file. Is there a patch for this, if
>not which source file needs to be modified in order to fix the
>frequencies?
>Thank you,
>Morteza
I can't tell you which file needs to be modified but just in case
you are not aware of how to do it you need to ensure that
at least three MIDI messages are used.
The first, to be on the safe side, is a Registered Parameter number
message which sets the pitch wheel sensitivity. Although the MIDI
standard suggests that all MIDI devices default to 2 semitones
up and down from the central position it would be a good idea to
ensure that in a file using quarter tones that this is set.
Controller 101 sets the coarse value, semitones, and controller
100 the fine in hundreds of a semitone. Next for each quarter tone
desired you need to prefix it with a pitch wheel message to
shift it's pitch in the desired direction and then send the note
on event and then reset the pitch wheel back to the central position
unless the next note on the channel is modified in pitch in which
case you need to move the pitch wheel to the desired position.
For the gory details see:
http://www.borg.com/~jglatt/tech/midispec.htm
Hope this helps.
Nigel.
_______________________________________________
Lilypond-devel mailing list
address@hidden
http://mail.gnu.org/mailman/listinfo/lilypond-devel