The aim is to have an open framework where notation for newer effects can be easily added and strategies for rendering these effects can be experimented with.
The generated music uses a harmonic scale where 8 "pure" notes in an
octave are placed at
ratios 1, 9/8, 5/4, 4/3, 3/2, 5/3, 15/8, 2/1. Positions of rest of
the notes is less certain.
The thoery of Indian music prescribes 22 notes in an octave and their
positions are not known
(the so called "shruti samasya"). We are currently making
measurements
to ascertain these positions.
We have fixed the syntax for core level notation and constructed a synthesis engin for rendering these notes. A compiler program translates from the high level music notation to low level code handled by a synthesis engin. Below, we give an example of music in such a notation and the resulting sound files. Currently we are experimenting with notation for meends and their rendering.
Example 1
define teental as
pat( dha, dhin, dhin, na | na, dhin, dhin, na | na, tin, tin, na |
na, dhin, dhin, na ) ;
main tempo=120 tabvol=77 insvol=81
2*poly( 3:teental,
pat(G,R,2.G |R,S,R,S | S,D-,P-, D- | 2.S,R, G |
R, 2.P, G | G, R, 2.G | P, 2.pat(G, 2.P, D), S'| S', 2.D, P|
G, R, S , R | 2.D-, S,R |
8.pat( 3%G, R ,2.G, 3%D-,S, R, 3.G, 3%P-,D-,S,R,2.3%G)
)
).
Explanation (very sketchy):
2*pat play pattern at twice the current tempo.
3:pat play pattern three times.
2.pat fit the pattern to play in two beats at current
tempo.
3%pat increase the volume of pattern by 3db.
poly(pat1,pat2) plays patterns pat1 and pat2 in parallel
(simultaneously).
S,R,G,M ... notes of Indian music roughly C,D,E,F.. of western
notation.
D- means note D one octave down. R'' means note R two octaves
up.
dha, dhin, ... bols (sounds) of Indian drum instrument tabla.
Synthesized sound files:
Played as synthesized
reed instrument.
(Synthesis technique: Addative synthesis + ADSR envelop )
Played as synthesized
string instrument.
(Synthesis technique: Karplus-Strong Algorithm for plucked sound)
Played as sampled
santur instrument.
(Synthesis technique: Wavetable synthesis with sampled santoor sound).
Acknowledgements: The compiler construction system GENTLE was used for building program that translates from high level music notation to code handled by synthesis engin. The synthesis engin was built using the well-known software synthesis program CSOUND.A classical film song. Score and synthesized sound (.wav file) (large 5 Mbytes) A variety of tabla compositions: Score and Synthesized sound (.wav file) (LARGE 9 MBytes) Raag Durga in Ektal: Score and Synthesized sound (.wav file) (LARGE 10 MBytes)