tanpura - 7 notes?

Question

I overheard that indian music disputes the notion that 7 notes are equally divided. Hence, people should use tanpura (instead of harmonium or piano) to practice with. I googled about it, and I read that it only plays Pa Sa Sa Sa (or something like that). Can anybody shed light on the topic? Does anybody know some online tanpura that can play all 7 notes? (else how is one supposed to practice?)

Answer 1

See here to play a virtual live tampura and to read more about it.

As you'll find in text:

Having reference tone playing in the background can come in real handy here to help the bansuri player stay on pitch. Tanpura serves this purpose very well as it not only provides the root note Sa but Pancham or Pa (the fifth note) as well. Besides these, Tanpura produces a whole repertoire of rich harmonics (jawari in Hindi).

Also you'll find it helpful to read about quarter tone which is a basic component of many countries' traditional music in Middle-east and Central Asia. As you may know even having smaller note divisions in music of some countries is common.

You can watch a man playing quarter tones here.