Re: The Audiophoolery Thread.
Ah but Woolies is long defunct ;-)
Seriously though, bell wire is single strand, 0.5mm diameter. Which is a loop resistance of 0.17 ohms per meter. A 5 meter run would therefore be 0.87 ohms and at a peak current of 10A say from a decent amp would dissipate a peak power of 87W. Which is a trifle high.
I of course take your point. The good old QED 79 strand (£22 for a 5 meter pair) has a loop resistance of 0.016 ohms per meter. So the 5 meter run would have a loop resistance of 0.08 ohms and for 10A would disspate 8W. Which is still surprisingly high. Of course in the context of an 8 ohm loudspeaker producing 800W at that current the cable dissipation is only 1%.
To reduce it even further you just need to use more copper (or to get 6% less resistance, eek, silver). The QED silver signature, which actually uses copper, (£450 for a 5 meter pair) has 5.5 square mm and a loop resistance of 0.006 ohms per meter. So our 5 meter benchmark would be 0.03 ohms and dissipate 3W at 10A.
From bell wire to slightly insane we've gone from 0.87 ohms to 0.03 ohms. How significant the reduction is beyond cheap and cheerful QED 79 strand in most practical circumstances is certainly debatable.
Craig
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