I'm trying to figure out how to use the "-Z" (or "--freq_table") option of timidity to assign specific frequencies to midi note numbers, but there is no clear documentation online.]
How do I specify a frequency table for timidity?
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You may be interested in taking a look at temperanotes (albeit it's in its infancy) – Davide Dec 23 '16 at 4:29
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The file is a list of 128 integers -- each of which is the frequency of the corresponding midi note in miliHertz. The first line gives the frequency for midi note 0, the next for midi note 1 and so on.
For A440, 12-tone equal temperament, lines 65-72 (inclusive) would be:
--lines 1-64 (midi notes 0-63) snipped >> # next is midi 64 329628 349228 369994 391995 415305 # next is midi 69 440000 466164 493883 -- lines 73-128 (midi notes 72-127) snipped >>
The file can contain comment lines that start with a # character; note that placing a comment after an entry will cause problems, i.e.
414305 440000 # a comment like this will cause problems 466164
I think that putting comments after the entry causes the whole line to be ignored but I haven't tested this.
The following python snippet spits the file for A440, 12TET:
f0=440.0
midi0=69
print "# A440 12-TET"
for i in xrange(128):
print int( f0*2.0**( (i-midi0)/12.0 )*1000+0.5 )
To have octave repetition of the same table do something like
table=[1.0, 16.0/15, 9.0/8, 6.0/5, 5.0/4, 4.0/3, 45.0/32, 3.0/2, 8.0/5, 5.0/3, 16.0/9, 15.0/8]
f0=440.0
midi0=69
print "# A440 just intonation"
for i in xrange(128):
(octave, index)=divmod( i-midi0, len(table) )
print int( 2**octave*table[index]*f0*1000+0.5)
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Correction in the code for the 12TET tuning, must cast
(i-midi0)to a float before dividingprint int( f0*2.0**( 1.0*(i-midi0)/12 )*1000+0.5 )– Trevor Ian Peacock Sep 4 '16 at 14:43 -
Thanks, this description has been very useful to kickstart the development of temperanotes – Davide Dec 23 '16 at 4:29
