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DIY Speaker wire

I have read multiple posts about using 10 awg solid core copper wire for speaker wire. Anybody use 10-3 romex? It has 3 shielded wires and one bare inside a plastic sheath. I am bi- ampping and am considering using this for each side instead of (4) single wires.
jonoulman

Showing 2 responses by kijanki

kijanki's avatar
kijanki
4,453 posts
 
Gauge 10 has resistance of 0.001ohm per foot making 10' typical cable (both ways) 20x0.001= 0.020ohm while at the same time inductor in series with the woofer is likely to have 0.1ohm
kijanki's avatar
kijanki
4,453 posts
 
Unfairlane, Tube amps present higher output impedance being power source vs voltage source that SS amps are. I was just trying to show that cable thickness is pretty much irrelevant because woofer choke has 5x higher resistance (not to mention impedance of the speaker itself that is mostly resistive). As for thick wires going to power supply caps - it is because current is charge is delivered to capacitors in very short current spikes of very high amplitude. This amplitude is much higher than any output current you'll ever see.

There might be another reason for using thick cables and it is inductance. Inductance of typical gauge 18 wire is in order of 350nH per foot while it is less than 300nH for gauge 10. It represents about 0.9 ohm of inductive reactance at 20kHz for 10' cable.
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