Wiring options for new HT room

[PaulF]

I have just completed framing on a new room and need to start wiring out for audio but before pulling the trigger wanted to solicit some feedback on wiring options.

The front speakers will be B&W 802Ds with matching HTM2D center. B&W highly recommends maintaining a lead (inc. connectors) resistance of less than 0.1 ohms. The run to the front three speakers is approx. 40 ft.

I researched 10 AWG options and started to look at Belden 5T00UP for in wall installation before finding my way to their 1313A which is supposed to be better. I called BJC which makes speaker cables from Belden 5T00UP and Kurt told me 10 AWG was overkill and that if any speaker manufacturer recommended that I must maintain 0.1 lead resistance I should pack up the speakers and send them back. So I called B&W and they reiterated that 12 or even 10 AWG was appropriate if that's what it took to keep the suggested 0.1 ohm lead spec.

So my questions to others.

- Has anyone run 10 AWG speaker wire in their setups? What did you use?
- If you are using 10 AWG wire, did you terminate them, and with what?
- Did you run the speakers cables through a port in the wall (at the speaker end) or terminate in a wall plate? The latter allows for a nicer looking cable from the wall to the speaker than what you find on the typical spool.
- I am also planning balanced interconnects to the subs. Same question as above for this application.

 

[PaulF]

I was also thinking of biwiring the front L/R but with spool wire it would leave me with two not so great looking cables. Has anyone used a 14 or 12 AWG four conductor cable and paired up the conductors?

I am assuming the two lower gauge pairs will be of sufficient size when biwiring.

 

[MDS]

10 gauge wire would be overkill and that stuff is impossible to work with.

I think the rule of thumb is to try to keep the resistance of the wire to 5% of the nominal impedance of the speaker. For a 40 foot run you can even get away with 16 gauge, although I'd step down to 14 gauge just for peace of mind.

All of my speakers, except the front three, are connected to wall plates. I didn't see the need to run the front three to a wall plate when you still need to connect wire from the wall plate to the speakers themselves.

 

[PaulF]

I have read the 5% rule of thumb too, but 5% of 8 Ohms is 0.4 Ohms and I'm sure B&W know this. The 802Ds are notorious for dipping to 3.5 Ohms for a large portion of the mid frequency range, perhaps this is why B&W specs tighter?

Have you seen the Belden 1313A? It's supposed to be high count multi-strand for flexibility but understand the thicker gauges will obviously flex less.

 

[Rickster71]

With a 4-Ohm load and 14-AWG 40ft is max. I'd go bigger.

If it were me and I was wiring a pair of $12K 3.5 Ohm speakers, I certainly wouldn't quibble over wire!
I'd use 12-AWG 4 wire, or a 10-AWG 2 wire.

 

[PaulF]

Yeah I don't know why people keep telling me that 10 AWG is expensive when we are talking about spool wire, they are sources for Belden all over the web and the premium from 12 AWG is not that much.

B&W said minimum would be 12 AWG but 10 AWG over that distance would provide more dynamics. Belden reminded me that the wire resistance must be doubled relative to the distance because the circuit includes the run to the speaker and back.

So if Belden 1313A has a resistance of 1 Ohm for 1000 ft, then my 40 ft run will have 80 ft of wire and 0.08 Ohms resistance not accounting for any connectors which is already very close to B&W's recommended 0.1 Ohms.

 

[Rickster71]

Yeah I don't know why people keep telling me that 10 AWG is expensive when we are talking about spool wire, they are sources for Belden all over the web and the premium from 12 AWG is not that much.

B&W said minimum would be 12 AWG but 10 AWG over that distance would provide more dynamics. Belden reminded me that the wire resistance must be doubled relative to the distance because the circuit includes the run to the speaker and back.

So if Belden 1313A has a resistance of 1 Ohm for 1000 ft, then my 40 ft run will have 80 ft of wire and 0.08 Ohms resistance not accounting for any connectors which is already very close to B&W's recommended 0.1 Ohms.

It makes the idea of running 12-AWG 4 wire and doubling them up your best bet.
Four 12-AWG wires doubled up, have more area than one 10-AWG wire.