Know I'm a little bit outside these groups, but I need some advice on
tuning a VEENA. I know you use only two or at the most three of the
fretted strings, but how about the three open side
strings?
If you mean the 3 TALA strings by calling "open side string ". The first one should be the Sa same as the main 1st string, second will be PA as high and third one as high Sa. just like SA Pa SA as we sing before start of Karnatic session. I hope answer your question