Tuning Tables

A tuning table is a text representation of a scale that can be interpreted by an external program. This is usually used to tune a synthesizer or other sound source so that the scale can be used in a musical composition.

Some tuning tables – such as that used by Scala – describe the scale in absolute terms, but most need to have a reference defined so that the scale degrees can be mapped to a frequency. For this purpose the PyTuning package has adopted the MIDI standard for note numbers and frequencies.

Octave	C	C#	D	D#	E	F	F#	G	G#	A	A#	B
-2	0	1	2	3	4	5	6	7	8	9	10	11
-1	12	13	14	15	16	17	18	19	20	21	22	23
0	24	25	26	27	28	29	30	31	32	33	34	35
1	36	37	38	39	40	41	42	43	44	45	46	47
2	48	49	50	51	52	53	54	55	56	57	58	59
3	60	61	62	63	64	65	66	67	68	69	70	71
4	72	73	74	75	76	77	78	79	80	81	82	83
5	84	85	86	87	88	89	90	91	92	93	94	95
6	96	97	98	99	100	101	102	103	104	105	106	107
7	108	109	110	111	112	113	114	115	116	117	118	119
8	120	121	122	123	124	125	126	127

So, for example, note number 69 corresponds to middle A, whereas 60 corresponds to middle C. The frequency standard is 12-EDO, and the note 69 is pegged to 440 Hz. Thus if you passed 69 as the reference note, the 69’th entry in the table would be 440 Hz and this would correspond to the first degree of the scale. 60 would cause the first degree of the scale to be assigned to that note number (with a corresponding frequency of about 261.6 Hz). The timidity soft synth is an example of a synthesizer that needs this reference note and frequency.

In general the table will need to be output to disk so that it can read by the program. This can be done with something like:

from pytuning.tuning_tables import create_timidity_tuning
from pytuning.scales import create_euler_fokker_scale

reference_note = 60
scale = create_euler_fokker_scale([3,5],[3,1])

tuning = create_timidity_tuning(scale, reference_note=reference_note)

with open("timidity.table", "w") as table:
    table.write(tuning)

This will cause the generated scale:

to be written to a disk file, timidity.table, which can be understood by timidity:

timidity -Z timidity.table score.mid

Timidity

Scala

The Scala tuning table can be used with the Scala package, but it can also be used to tune the soft synth Zynaddsubfx, as well as its derivative Youshimi. With the soft synths you will need to explicitly set the reference note and frequency in the scale GUI.

Fluidsynth

Csound

For use in Csound PyTuning will generate a table of frequencies that can be used as a table lookup, mapped to MIDI note number. As mentioned in the basic concepts, the easiest way to use this is via the table opcode:

inote     init          p4
iveloc    init          p5
ifreq     table         inote, 1
a1        oscil         iveloc, ifreq, 2
          outs          a1, a1