Unless you're wanting to drop a ton more money, I wouldn't worry about the specifics for the materials. There are, however, several things you can do . . .
I'm assuming that this is typical residential construction, wood studs wired with Romex, rather than wires pulled in conduit. First, establish a rapport with your electrican - both the guy actually doing the work, and his supervisor. It doesn't hurt to keep your GC in the loop as well, as some of them are sensitive to people "going around" their authority on the jobsite. If you devote some of your budget to beer for the workers, it's usually money well spent.
Here's a quick list of tiny things that make a big difference:
1. Have everything wired with 12ga Romex instead of 14ga. It's easy to tell - 12ga is always yellow these days. Going bigger than 12ga will usually get moans and groans from the electicians, as it starts getting heavy, harder to pull, and harder to fit through various boxes and fittings - and harder to twist together, fit on the devices' screw terminals, and stuff in the boxes. And 12ga is plenty big.
2. If there are multiple circuits for the audio/video system, have all of them put on the same electrical phase - that is, on the same conductor of the SEC cable coming from the meter. This will greatly reduce the amount of ground-leakage (hum) current flowing between your components.
3. Keep all lighting loads off of the system circuits. If you have a lot of dimmed lighting loads, a lighting control system (i.e. Lutron Homeworks, etc.) or any special lighting loads (neon, cold cathode, dimmable flourescent, etc.), put them on the OPPOSITE phase from the system circuits. This will minimize the transmission of noise from lighting systems onto your audio system circuits.
4. Use good commercial-grade outlets. No need to get tweaky about it, but you might want to go and buy them yourself. Go to an electrical supply house, tell the guy at the counter that you want some of the good ones, and he/she will probably instantly know exactly what you mean. Hubbell, Pass & Seymour, Lutron, and even Leviton make some nice ones, but P&S and Leviton also make cheap ones too, so don't just go by brand. They will most likely have a clamp mechanism where the side screws actually tighten down the wire against the contact, rather than a stupid pressure-fit "cinch" connection.
5. If by chance the outlets do have pressure-fit cinch connections, make sure that the electrician doesn't use them -- rather, the wires should be wrapped around the screw terminals and tightened.
6. Have your electrician twist together all of the wires before putting on the wire nuts. Really. Most don't. You might even spot-check their work at night when they're gone.
7. If the wiring is done with armored (MC) cable and metal boxes, or metal boxes on metal studs, then using isolated-ground receptacles is a good idea. Otherwise, don't worry about it.
8. If there is conduit and pulled wire, then insist that there are separate neutral runs for each circuit . . . some electrical codes will let them share. With metal conduit and boxes, use isolated-ground receptacles.
9. Buy a cheap outlet tester, and check all of the outlets yourself after they're installed.
Following the above might easily blow your budget, and it will take a bit of time and add a bit more stress to your life. But it will make a big difference.
I'm assuming that this is typical residential construction, wood studs wired with Romex, rather than wires pulled in conduit. First, establish a rapport with your electrican - both the guy actually doing the work, and his supervisor. It doesn't hurt to keep your GC in the loop as well, as some of them are sensitive to people "going around" their authority on the jobsite. If you devote some of your budget to beer for the workers, it's usually money well spent.
Here's a quick list of tiny things that make a big difference:
1. Have everything wired with 12ga Romex instead of 14ga. It's easy to tell - 12ga is always yellow these days. Going bigger than 12ga will usually get moans and groans from the electicians, as it starts getting heavy, harder to pull, and harder to fit through various boxes and fittings - and harder to twist together, fit on the devices' screw terminals, and stuff in the boxes. And 12ga is plenty big.
2. If there are multiple circuits for the audio/video system, have all of them put on the same electrical phase - that is, on the same conductor of the SEC cable coming from the meter. This will greatly reduce the amount of ground-leakage (hum) current flowing between your components.
3. Keep all lighting loads off of the system circuits. If you have a lot of dimmed lighting loads, a lighting control system (i.e. Lutron Homeworks, etc.) or any special lighting loads (neon, cold cathode, dimmable flourescent, etc.), put them on the OPPOSITE phase from the system circuits. This will minimize the transmission of noise from lighting systems onto your audio system circuits.
4. Use good commercial-grade outlets. No need to get tweaky about it, but you might want to go and buy them yourself. Go to an electrical supply house, tell the guy at the counter that you want some of the good ones, and he/she will probably instantly know exactly what you mean. Hubbell, Pass & Seymour, Lutron, and even Leviton make some nice ones, but P&S and Leviton also make cheap ones too, so don't just go by brand. They will most likely have a clamp mechanism where the side screws actually tighten down the wire against the contact, rather than a stupid pressure-fit "cinch" connection.
5. If by chance the outlets do have pressure-fit cinch connections, make sure that the electrician doesn't use them -- rather, the wires should be wrapped around the screw terminals and tightened.
6. Have your electrician twist together all of the wires before putting on the wire nuts. Really. Most don't. You might even spot-check their work at night when they're gone.
7. If the wiring is done with armored (MC) cable and metal boxes, or metal boxes on metal studs, then using isolated-ground receptacles is a good idea. Otherwise, don't worry about it.
8. If there is conduit and pulled wire, then insist that there are separate neutral runs for each circuit . . . some electrical codes will let them share. With metal conduit and boxes, use isolated-ground receptacles.
9. Buy a cheap outlet tester, and check all of the outlets yourself after they're installed.
Following the above might easily blow your budget, and it will take a bit of time and add a bit more stress to your life. But it will make a big difference.