Gaganji:
Welcome to RO. And thanks for the pix! When you say "religious studio", do you mean a broadcasting studio? A recording studio? Are you trying to correct the studio monitor system, or the program that's being broadcast/recorded? We need more information here. Typically, an EQ like that one is used to "gently" adjust the slight dips and peaks in a sound systems frequency response. There really is no "right" way to push the sliders, except to not push them very far up and down. I will say, however, that the way they are set in the photo is NOT the way they should be in actual use!

I will add that you should start off "centering" all of the sliders (the 31 bands) at their "O" point-no cut or boost. Then pull the very lowest bands (20, 25, 31.50 Hz) down maybe 6dB or so. There is very little actual musical program material that low, even for a tabla. That low area is usually low frequency artifacts like mic stand rumble, thumps, and "pop" blast noises from microphones. And you can start on the rotary Low Cut Filter set at around 40Hz. Set the High Cut Filter all the way "open" (30KHz) to keep it from cutting the highs (for now).