Rhythm Indian rhythms are based on tals or talas, cycles (sometimes complex) which do not at all correspond to the western notion of "bars" of music. Tals are seldom the sole source of borrowing in jazz fusion efforts, but often accompany other elements.
Scale There are far more scale possibilties than those familiar to Western audiences; these include the major, the harmonic minor, the melodic minor, and the seven "modes" first described in print by Pythagoras. Classical Indian music makes use not only of dozens of other scales,but also utilizes quarter tones not present in Western music, rendering hundreds of additional scales possible.
Form Classical Indian performances are based around the concept of raga, which is somewhat difficult to describe in brief. A raga is not a composition per se, but rather consists of a particular combination which includes one or more recognizable melody lines, a distinct scale (which may differ in the ascending and descending), and a particular tal (rhythm cycle). Ragas, like symphonies, consist of movements, although these movements are not separated by pauses in playing. A raga usually commences with an alap, a slow section described as having an "improvised rhythm," and gradually unfolds through other such sections with a growing complexity and (generally) increase in tempo. Unlike a symphony, a raga is not composed note-for note; rather, the scale, the rhythm cycle, and the melody serve as guidelines within which improvisation is a significant element.
Melody Precisely because of the improvisational nature of Classical Indian music, melody is the rarest element borrowed by Western musicians. That is not to say, however, that it is completely absent; ragas do contain "catch-phrases" {pakads}, and there are many other types of compositions in Indian music which do contain substantial melodies (including devotional songs, folk songs, lullabies, and other song varieties).
There is another element, instrumentation, which i consider to be worthy of far less consideration, because use alone of Indian instruments (especially the sitar) does not necessarily reflect inspiration specifically from the Classical repertoire, nor even (depending on the usage of the instrument) Indian music at all.
Of course, it's impossible to make consise distinctions on which to base my decisions for inclusion or exclusion of listings in this Guide. I am counting on the Internet community to keep me informed of new developments in Indian/Western fusion, and also to continue my education in this deligtful genre by sending me corrections, additions, updates, etc, at
indyjazz@lutins.org.