Urgent help: fuse breaker box for dedicated line?

Hi,
I'm in process of building a listening room, and the contractor will do the dedicated line for me. However, I have to supply all the parts, and I want all the parts will be ready before the contruction starting.
I want to buy all the parts now just because I'm off for the whole week. I'll be busy next week and I don't want to wait for the contractor until next Monday.
I already have dedicated lines in my old room, so I know little about it except for the fuse breaker box, and I don't know where the last electrician bought it.
Thanks!
DT

When asking an electrician for dedicated lines, I advise you to include overload protection as well in the case lightning should strike in the direct vicinity of your home(s). Small extra investment, large amout of security.

I'll second the need for an electrician. Your 240v sub panel will provide 120v. Just use a 1 pole(slot) breaker. 240v would require a two pole breaker. Sounds to me as if your using a fuse box, in that case your hot leg off the fuse and your neutral would comprise the circuit, with the ground for safety purposes. If you double the voltage you cut the current in half, that is why transmission lines aren't the diameter of sewer pipes. If your only running your audio equipment one circuit will suffice. You should pull romex wire 12 guage 3 conductor or 12/3. Thinn is stranded wire with an insulation that is oil resistant. Email me if you have any other questions. Mdoughty@nycap.rr.com

DT. You might try going to a wholesale electrical warehouse where electricians buy their parts from. They might even be able to sell you the box you're looking for and they would be most qualified to answer your questions. Usually in the morning and late afternoon trade people always around.

Are you pulling out of your regular house breaker panel? If so, All you need is a breaker(single pole) of the same brand breakers that are in your box. Using one pole will give you the 120v you desire. Every wire in your house should go back to this breaker panel. If the panel is full(no extra slot) then you have a little bit of a problem. You DO NOT need to install a second disconnect box if you are pulling from your panel. That would be redundant.
You can get single pole breakers of various amperages.
Since you are running a dedicated line, I would run 10/2 Romex.
If you are having a licensed electrician do the actual work, ask him what you need. Also, you may want to get a high grade outlet such as a Wattsgate or Hubbell for your outlet.
By the way---contrary to popular belief, A lot of electricians buy their stuff at Home Depot and Lowes. Both stores offer a "Commercial" sales department and carry a good supply of materials at a reasonable price.