Cable Specs

[RedStep]

OK, I'll give this a shot... :?

When looking at speaker cable specifications, What should your focus be??? In conjunction with your output source...Is it impedance, or capacitance, or what???




RedStep
We are truly a product of the decisions we make

[Lex]

Well, I believe that inductance and resistance are more important than Capacitance for speaker cables. I will be interested in hearing Jon Marsh's explanation here. Hard to go wrong with OF copper in teflon, or silver in teflon for speaker cables, IMO. There's mixed results I think with stranded versus solid core wire.

Lex

[JonMarsh]

I agree with Lex that resistance and inductance are the number one parameters- but capacitance winds up being an important consideration, because many of the layups which have been tried to reduce inductance as a byproduct increase capacitance.

In the 40th anniversary issue of Sterephile, one of the products mentioned as a top 100 product in the last 40 years was the Polk audio braided speaker cables introduced in the mid 70's- these were the first low inductance litz like speaker cables commercially promoted, to the best of their knowledge- and mine. I bought a few sets, and have used the cable for internal wiring in power amps and speakers. But while having very low inductance, it also had more distributed capacitance then heavy gauge zip cord, and some power amps with high feedback and marginal stability really didn't like seeing 15nF to 25nF of capacitance at the output terminals! Strangely, this was a worst case scenario for a number of amps, since some, with higher capacitance, slowed down enough that they became stable again. This is a by product of using a two pole plus zero loop compensation scheme in order to raise the audio passband negative feedback with a relatively slow output stage.... of course, mine were stable with 10nF, 50nF, or 1uF on the output.

For longer runs of cable, inductance can result in measurable and audible roll off of the top end. I've even found audible variations in lengths like 12 - 14 feet.


Regards,

Jon




Earth First!
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[Brandon B]

Jon -

Did you ever get a chance to do an inn-depth workout of the Risch type 82859 cross connects?

BB

[RedStep]

So, in considering speaker cable: keep resistance (impedance) and inductance low, and capacitance in moderation.

:?: Shouldn't you look at the output impedance of the component and match the cables DC resistance???

:?: And second question is what are good mesurments to look at, or what are some good #'s.....




RedStep
We are truly a product of the decisions we make