Lots of good stuff in the archives as Rushton suggests. However, I can't resist saying a couple of things.
Regular Romex type of housewire is fine. It will be 12/2 for a 20 amp circuit. I have no idea what else you could possibly use anyway, at least if you want to comply with electrical code. The code is a little bit fussy about what type of wire gets buried in walls.
If you add a 20 amp circuit and 12 gauge wire, make sure that your outlets are rated for 20 amps. If you put 15 amp rated outlets on a 20 amp circuit, not only will you be in violation of code, but you will be creating a fire hazard. And your house insurance won't pay up if they find out about it.
Twenty amps is fine, although some people like to run heavier circuits. However, if you want to be careful about having enough power, you can do a simple calculation. Twenty amps times 120 volts = 2400 watts in total capacity. Reduce by 20% for safe capacity. Therefore, the safe capacity for a 20 amp circuit is 1920 watts. Now add up the wattage of everything that's going to be plugged into it. If you're under the safe capacity, you're fine. Farther under is better so that in music peaks, the current draw doesn't spike up above safe or total capacity.
Regular Romex type of housewire is fine. It will be 12/2 for a 20 amp circuit. I have no idea what else you could possibly use anyway, at least if you want to comply with electrical code. The code is a little bit fussy about what type of wire gets buried in walls.
If you add a 20 amp circuit and 12 gauge wire, make sure that your outlets are rated for 20 amps. If you put 15 amp rated outlets on a 20 amp circuit, not only will you be in violation of code, but you will be creating a fire hazard. And your house insurance won't pay up if they find out about it.
Twenty amps is fine, although some people like to run heavier circuits. However, if you want to be careful about having enough power, you can do a simple calculation. Twenty amps times 120 volts = 2400 watts in total capacity. Reduce by 20% for safe capacity. Therefore, the safe capacity for a 20 amp circuit is 1920 watts. Now add up the wattage of everything that's going to be plugged into it. If you're under the safe capacity, you're fine. Farther under is better so that in music peaks, the current draw doesn't spike up above safe or total capacity.