Shruti box or tune box: How to start

[vss]

Hi all,
I am not familiar with electronic instruments and circuits. However I am interested in designing a musical instrument, used as a reference for musical notes (called shruti-box or swar peti in India, a tune box may be), that continuously emits a particular note sound.

I want to start reading material, references about loud speakers, varying input frequency (tuners?), volume etc.

Now question is how do I start...

[winner]

if u want only a single frequency note 2 b produced the best option would be to make 1 using ic 555 in astable mode go thru the datasheet
say freq in 440 hz then f=0.693(ra + 2*rb)*c
f=freq ra rb are resistors and c is capacitor substituting appropriate values for resistors and capacitors u get the desired freq on pin 3 of ic connest it to a speaker thru a 1 micro farad capacitor

[routhun]

555 timer in astable mode generates a square wave, which I guess is not needed by vss. He might be interested in pure sinewave for his shruti box.

vss, you might want to look a audio signal generator based on XR2206 chip which generates pure (almost) sinewaves. Ofcourse you need an oscilloscope to calibrate this box. Search diyaudio forums for XR2206 you'll find good amount of information

Thanks,
Routhu