If you have not started the wiring yet, the first thing you need to do is spec the main electrical panel to be Square D QO. The Square D QO panel has copper plated buss not aluminum as many have. Make sure it is not the Square D home Line brand, it has aluminum buss.
Next pay the extra $$ and have copper wire installed from the electric meter to the main electrical panel, not aluminum. The utility companies wire to the meter will be aluminum, nothing you can do about that.
How far will your audio room be from the main electrical panel? Approximate, don't forget to figure up and down. If the length are approaching 70 ft or more you may want to consider a sub panel closer to your equipment.
As for the number of branch circuits Walkelin pretty much covered it in his post. Cheaper now than later down the road.
Next pay the extra $$ and have copper wire installed from the electric meter to the main electrical panel, not aluminum. The utility companies wire to the meter will be aluminum, nothing you can do about that.
How far will your audio room be from the main electrical panel? Approximate, don't forget to figure up and down. If the length are approaching 70 ft or more you may want to consider a sub panel closer to your equipment.
As for the number of branch circuits Walkelin pretty much covered it in his post. Cheaper now than later down the road.