Christopher's Persian Classical Music Intervals Page Back to Christopher's Music Page 23 May 2002

Here's some information I originally compiled for an article I posted to The Alternate Tunings Mailing List:


OK, first a disclaimer: the easiest way to get two Persian music theorists in an argument is to ask them what the actual intervals of Persian music are. :-)

I think one of the things that strongly influences the placement of frets for Persian music is that in the course of playing a Dastgah one modulates through many subsidiary Gusheh-ha by changing tonics. So, the ability to change keys is a major factor. I think it was partly for this reason that Vaziri was such a big fan of 24 tET -- since then one can change to any key and still play all the intervals consistently. The other two groups of fixed tunings that seem to be popular are tunings built up of fifths (as promoted by theorists such as Barkechli) or of fifths and thirds (based on observations by Farhat, et al).

Despite the above, most of what I have heard and read from Persian musicians (as opposed to Persian music theorists) is that the ideal intervals for all the Gusheh-ha of all the Dastgah-ha can not be reduced to a fixed set, which is why there are moveable gut frets on those Persian lutes which are not fretless. The musicians adjust their frets depending on the sequence of Gusheh-ha they are about to play.

A note about the following notation ("p" & ">"):

Ep is "E koron"
F> is "F sori"

This is an ASCII-ified version of the symbols Vaziri introduced to allow Persian classical music to be written in western classical notation.


Barkechli's Persian scale is basically a 17-tone Pythagorean scale (this is from PYTH_17.SCL from Scala):
interval ratio cents note name description
0 1/1 0.000 C unison, perfect prime
1 256/243 90.225 Db Pythagorean limma
2 2187/2048 113.685 Dp apotome
3 9/8 203.910 D major whole tone
4 32/27 294.135 Eb Pythagorean minor third
5 19683/16384 317.595 Ep Pythagorean augmented second
6 81/64 407.820 E Pythagorean major third
7 4/3 498.045 F perfect fourth
8 1024/729 588.270 F> Pythagorean diminished fifth
9 729/512 611.730 Gp Pythagorean tritone
10 3/2 701.955 G perfect fifth
11 128/81 792.180 Ab Pythagorean minor sixth
12 6561/4096 815.640 Ap Pythagorean augmented fifth
13 27/16 905.865 A Pythagorean major sixth
14 16/9 996.090 Bb Pythagorean minor seventh
15 59049/32768 1019.550 Bp Pythagorean augmented sixth
16 243/128 1109.775 B Pythagorean major seventh
17 2/1 1200.000 C octave


Farhat, in his doctoral thesis, gives the following as the average of several observed tar and sehtar tunings:

Farhat's Observed Tuning
interval cents note name
0 0.000 C
1 90.000 Db
2 135.000 Dp
3 205.000 D
4 295.000 Eb
5 340.000 Ep
6 410.000 E
7 500.000 F
8 565.000 F>
9 630.000 Gp
10 700.000 G
11 790.000 Ab
12 835.000 Ap
13 905.000 A
14 995.000 Bb
15 1040.000 Bp
16 1110.000 B
17 1200.000 C

The following (PERSIAN.SCL from Scala) is similar to Farhat's observed tuning and can be thought of as being built up of fifths and thirds.

Another way of thinking of it is to build it up from fifths and syntonic commas:

Start with a Pythagorean scale containing no koron or sori notes.
To get a koron note add two syntonic commas to a flat note.
To get a sori note, subtract two syntonic commas from a sharp note.
[A syntonic comma is the ratio 81/80, about 21.506 cents.]

Persian Tar Scale, from Dariush Anooshfar, Internet Tuning List 2/10/94
interval ratio cents note name description
0 1/1 0.000 C unison, perfect prime
1 256/243 90.225 Db Pythagorean limma
2 27/25 133.238 Dp large limma
3 9/8 203.910 D major whole tone
4 32/27 294.135 Eb Pythagorean minor third
5 243/200 337.148 Ep acute minor third
6 81/64 407.820 E Pythagorean major third
7 4/3 498.045 F perfect fourth
8 25/18 568.717 F> classic augmented fourth
9 36/25 631.283 Gp classic diminished fifth
10 3/2 701.955 G perfect fifth
11 128/81 792.180 Ab Pythagorean minor sixth
12 81/50 835.193 Ap acute minor sixth
13 27/16 905.865 A Pythagorean major sixth
14 16/9 996.090 Bb Pythagorean minor seventh
15 729/400 1039.103 Bp acute minor seventh
16 243/128 1109.775 B Pythagorean major seventh
17 2/1 1200.000 C octave

Vaziri's scale is just a subset of 24 tET:

Vaziri's Tuning
interval cents note name
0 0.000 C
1 100.000 Db
2 150.000 Dp
3 200.000 D
4 300.000 Eb
5 350.000 Ep
6 400.000 E
7 500.000 F
8 550.000 F>
9 650.000 Gp
10 700.000 G
11 800.000 Ab
12 850.000 Ap
13 900.000 A
14 1000.000 Bb
15 1050.000 Bp
16 1100.000 B
17 1200.000 C

I believe Vaziri actually had more than 17 frets per octave on his tar, but I can not remember if he had all 24 frets per octave or a subset that was 17 < n < 24. I will try to remember to update this page if I come across the information again.


Bibliography

The Dastgah concept in Persian music. Farhat, Hormoz (Los Angeles) 1966 [also:] Cambridge (England) 1990

Musique d'Iran Nelly Caron et Dariouche Safvate Paris : Buchet/Chastel 1997 [in French]

Traditional Persian art music: The Radif of Mirza Abdollah Tala'i, Dariush Costa Mesa : Mazda, 1998 [set of book + 5 CDs] [Click on the title to go to Mazda Publisher's home page for this book/CD set.]

Classical Persian music; an introduction. Zonis, Ella. Cambridge, Mass. 1973

The radif of Persian music : studies of structure and cultural context in the classical music of Iran. Nettl, Bruno, 1930- Rev. ed. Champaign, Ill. 1992