OT: For Mere Mortals

GM · April 10th, 2013, 11:13 PM

Choosing wire size is a function of voltage drop over distance, so as long as the peak current requirement doesn't dictate an unacceptably large wire gauge for the app to maintain a low voltage drop, then there should be no perceived loss of sound quality [SQ] regardless of length.

GM

**bowtie427ss** · April 11th, 2013, 06:56 AM

Roger Russell is a great fellow, he is very knowledgeable, he is NOT the God of speaker wire, however.

If an inductor was simply a "conductor", that's what science would have called it.

A 75foot pair(speaker wire) is 150 feet of circuit. Be sure to remember this complex math when consulting the magic speaker wire length charts. The posters of these tables and charts always seem to neglect this little diddy.

The electron is a wonderful thing, understanding how various circuits and components affect it's behavior is even more so.

GM · April 11th, 2013, 09:30 AM

You've seen wire selection charts that don't consider the return path?

GM

**fpitas** · April 11th, 2013, 09:38 AM

Since we're talking about speaker wires, I thought I'd point out that they can affect the amplifier under some conditions. Here's some simulation data:

Loudspeaker Cable Characteristic Impedance

Rod's idea of RF terminating the cables is a good one in general. Nature abhors an unterminated cable ;-)

**wws944** · April 11th, 2013, 10:08 AM

Originally Posted by bowtie427ss

A 75foot pair(speaker wire) is 150 feet of circuit. Be sure to remember this complex math when consulting the magic speaker wire length charts. The posters of these tables and charts always seem to neglect this little diddy.

Actually Rogers table does take this into account. He even says so on his page.

He also states that when wire length is over 50 feet, reactive components start to become significant.

**Alien_Shore** · April 11th, 2013, 10:32 AM

This is a damn good read if you haven't already. GM (not *our* GM) makes some compelling points. You can get the teaser read here on google books:

Perfecting Sound Forever

**bowtie427ss** · April 11th, 2013, 10:38 AM

Originally Posted by GM

You've seen wire selection charts that don't consider the return path?

GM

Some of the charts i've seen give the specs for a single conductor relative to gauge and length, others do not specify one way or the other.

Probably was poor choice on my part to mention RR as his is one of the only commonly parroted tables that specifies clearly that it is for 2 conductor wire, many others do not.

I most often think of/refer to the chart found here where most of the specs are given for a single conductor as i would expect from a wire manufacturer: Peavey.com

But, where the specs for power and damping are concerned it gets confusing. Did they include data for both single conductors and pairs in the same table? Maybe this is not such a good reference after all?

**Old Guy** · April 11th, 2013, 04:15 PM

The problem with audio is no two sets of ears combined with a brain are exactly the same. the ears render the info, the brain interprets.

As far as speaker wire,have no problem with opinions with a qualifier.

I have to support about 90% of what Russell says. If somebody wants to use wire that doesn't make sense to me, hey it's their life. I don't believe in magic. I do believe there's a lot we don't know.

**wws944** · April 11th, 2013, 09:20 PM

Thing is, Roger doesn't say "speaker wire doesn't make a difference". In fact, he points out a number of cases where it certainly does make an audible difference. (The high resistance wires, the amp with ringing problems, the Monster Cable demo, etc.) Notice that he always qualifies his statements with the rule of thumb that the DCR of the speaker wire should be less than 5% of the total impedance of the speaker circuit.

In my case, my amp is less than 10 feet from the speakers. Take a common $0.50/ft speaker wire, say 12 ga Belden 5000UE. It has a DCR of 1.6 ohms/1000 feet. (Just looked it up at the Belden web site.) So I am looking at less than 0.016 ohms from the speaker wire. By Rogers ROT, with my 8 ohm ML-1Cs, the wire should be less than 0.4 ohms. So I am in great shape. If I go to smaller 14 ga 5100UE ($0.30/ft), the DCR goes up to 2.53 ohms/1000 ft. Since 0.0253 is still a factor of 20 lower than Rogers ROT, I am still in great shape. Why would I ever want to pay large sums for fancy speaker wire?

Zooming back a bit to non-speaker interconnects, one thing that (even slightly) more expensive interconnect cables do have is nice connectors. I do like cables with nice sturdy connectors that make good solid contact and have good strain reliefs.