Speaker wire re-visisted

[dynaco_dan]

Hi there;

I assumed in my prior writings about speaker cables, 10 guage Carol stranded perhaps, that everyone reading it knew that when you buy a 20' length per speaker, it is actually a 40' run.

Just as in an electrical extention cord, you are using AC and the signal supplies and returns from the speaker.

The only casual reading I have seen, is the increase of wire guage recomended for a 4 ohm ohm speaker, over that of 8 or 16 ohms speakers.

[rrcrain]

Speaker and interconnect wire is a topic where I walk the middle of the road. I've seen both change a systems sound, but I do not believe it was due to gauge or material the wire is made from but rather, the exotic braiding or other geometry of the wire.

Please note that I said "change" not "improve". If it's possible to improve the sound of a system using the "right" over priced wire, it's also equally possible to degrade the sound by using the "wrong" over priced wire.

From the reading I've done over the last 5 or so years, the best rational for using exotic interconnect wires is for impedance matching between amp and preamp. This "can" be an issue when rying to use equipment from different manufacturers. It may be solid state to tube or simply legacy equipment manufactured decades apart.

Granted, the sane and most cost effective solution is to buy compatable equipment rather than spending a few thousand on exotic wire to make the wrong stuff work togehter but it can be done with the right wire at only God knows what cost.

As far as speaker wire goes, It's my humble opinion it is the least effective upgrade, dollar for dollar, someone can make to their stereo system. The only difference I've been able to note on my system is the amplifiers run marginaly cooler, or seem to. My two amps are based on the original Leach Super amp design and can heat a small room on a cool day. With their massive heat sinks, the slightest breeze can rapidly drop heat sink temp by a few derees making subjective judgements highly questionable at best.

My opinion on the wire mess is this.

If your really interested in trying exotic wire, find a reputable shop that will let you audition the wire at home at no cost. If you're convinced it improved the performance of your system and like the price, go for it. If there's no change, take it back.

[dynaco_dan]

Hi there;

My only interest in speaker wire is that sufficient guage be used to handle the load at the other end.

My bringing this up again was because I assumed most people just go and buy a length of two wire, perhaps twice as long as needed, to cut in half per speaker length.

As long as the wire is not subject to physical damage then standard 2 - 18 wire lampcord can be used, as a minimum.

As the signal normally going to and from the speaker is AC, then we are actually sending the signal to and from the speaker.

If one has a 35' pair of speaker leads and 4 ohm speakers, then the guage is required to be, usually two guages heavier, than with 8 and 16 ohm loads.

The signal actually is travelling in this example, a distance of 70'.

I have had only one case where I had RF interference, that I heard.

Speaker cables should not parallel line voltage cables, but crossover at 90 degree angles when they are required to be close together.

The only protection from that problem, permanently that is, is to use shielded cable.

By shielded cable, I do not mean some isoteric $40.00/meter cable.

14, (lightest) 12 or even 10 guage (heaviest and best) BX armoured cable, the same as used in wiring commercial buildings.

Yes it's ugly but fully functional.

[rrcrain]

Interestingly, the bottom end of Kimber's speaker wire is braided so the conductors cross each other at 90 degrees. This is what I've been using for several years now. I won't tell you it improves the sound, but it also didn't make it worse. The biggest advantage I can see it looks decent and it eliminates parallel wires.

[soundminded]

>Interestingly, the bottom end of Kimber's speaker wire is

>braided so the conductors cross each other at 90 degrees. This

>is what I've been using for several years now. I won't tell

>you it improves the sound, but it also didn't make it worse.

>The biggest advantage I can see it looks decent and it

>eliminates parallel wires.

If you could get a speaker wire connected between a 4 or 8 ohm speaker load and a low output impedence voltage source like an amplifier to act as an effective radio antenna, that would be quite a trick. As it is, it's usually hard enough to get decent radio signals of a few dozen to a few hundred microvolts from a tuned dipole made from 300 ohm balanced antenna wire connected to a very high impedence load, the rf input of a tuner. If you want to know just how effective an rf antenna your speaker wire is or even how effective it is at inductively coupling 60 hz from power cords, turn off your amplifier and put your ear up to the speaker. Hear anything? I didn't think so. Most hum and rf noise in a sound system is coupled at the preamplifier signal level. I know, I lived 6 blocks from WTFM for years. The signal was so strong it came through channel 6 on my TV set and through my phono inputs but not through high level inputs. Some people claimed they could even hear it due to the metal fillings in their teeth and it drove them crazy.

Want to know how good your interconnect wires are? connect them as jumpers between the tape output and tape monitor input jacks of your preamp. The only rational test of how wire "sounds" is to compare it to a shunt, not to another wire and that is what you will do when you switch back and forth between source and tape monitor. I have never been able to detect any difference using one dollar Radio Shack wire. This is hardly surprising since I also could not detect any difference between a 7 mhz NTSC video signal run though one and the same signal fed as rf to the TV set's own tuner. That's 350 times the bandwidth of a high fidelity audio signal. You can try this yourself with a VCR. I think once an electrical engineering student has seen and solved the "telegrapher's equation" it should be impossible to sell him after market audiophile wires of any type. He KNOWS that wire is analyzed as a distributed parameter filter network by its lumped parameter equivalent. If he doesn't get it, he should ask for a tuition refund from his instructor. And how did I verify that this is true? From a Belden sales rep.

BTW, in the infamous Stereo Review test which showed Monster Cable was indistinguishable from 16 gage lamp cord, there was clearly a poorer audible result with 18 gage wire so that may be just a little too thin even for short runs, its dc resistance being relatively high. I use 16 gage exclusively myself and have no complaints.

[dingus]

here's a good read.

http://www.roger-russell.com/wire/wire.htm#introduction

[soundminded]

Electrical engineering students are required to solve network problems using mathematical models of wire to determine what effect they will have on such factors as maximum usable bandwidth for a given length of a particular type of wire. The major elements are series resistance, series inductance, and shunt capacitance. These last two elements serve to reduce signal level as frequency increases while series resistance reduces it at all frequencies. This is important for example in calculating how far from a telephone company central office, you can have a usable signal for a personal computer. This is why the phone company began installing low capacitance CAT5E and better wire and why people like me who live in a rural area far from a central office cannot get DSL service. It's also why you can't transmit even a single NTSC television signal over ordinary telephone lines without making some major compromises such as reducing the number of half frames per second...drastically.

Beleive it or not, people who work in the wire industry are not stupid and they are not indifferent to the technical needs of engineers to get maximum performance from their products. Quite the opposite, the standards for speaker wire and audio signal wire were set many decades ago and the technical requirements for them have not changed. Why should they, there are no changes to any of the factors for an ideal transmission element for them. The industry has devised the familiar products to satisfy these requirements cheaply and efficiently and that is why they have been so taken for granted. Examination of the frequency dependent elements of series inductance and shunt capacitance shows that for practically any conceivable audio system installation using ordinary wires, these are insignificant compared to the same parameters in loudspeaker system crossover networks and especially insignificant in comparison to the output circuit of a vacuum tube amplifier. It is true that increased series resistance will reduce the effective electrical damping an amplifier can provide in surpressing spurious bass resonances of speakers which are poorly mechanically damped at some frequencies, the reason for heavier wire gage as stated in the article. Increased series resistance exaggerates their inherent boominess. BTW, AR speakers when performing to spec are mechanically damped at a factor of 0.707, critical damping which is the ideal design. This is the most extended bass response for that speaker without a frequency response peak. I think it is true that some wires can be manufactured to have such high shunt capacitance or series inductance that they will slightly reduce the audible high frequency output of some loudspeaker systems. This may be useful for some shrill sounding loudspeakers but it comes at a heavy price, it can form a "tank circuit" which is in effect an oscillator at ultrasonic frequencies and in some marginally stable amplifiers can spontaneously destroy the output stage. BTW, you can get the same effect by just hanging a capacitor across your amplifier or speaker terminals and/or installing a series inductor of appropriate size.

I think the most remarkable thing about the marketing of speaker wires is that the manufacturers have convinced many consumers to buy these "LCR filters" at very high price, whose effect is unpredictable and maybe undetectable, and for which there is no control, when they could get exactly the desired results much more cheaply from an equalizer, a device intended for this purpose, yet they have persuaded the audiophiles to shun them like the plague. I think most professional audio engineers just shake their heads, laugh, and think to themselves that there's one born every minute.

[rrcrain]

Interconnect wire is a different animal than speaker wire, and on this topic, I will attest to hearing a difference from the rock bottom crap wire that Heathkit provided compared to decent wire from Radio Shack. The main difference was not sonic reproduction or some other exotic paramater invented by the magazines. It was 60hz hum rejection.

The original RCA interconnect wire was so horribly constructed it was location sensitive and had to be purposfully placed as far away from the power cords as possible. In those days, I went as far as to place every power cord in a braided steel sheath connected to ground, and this actually worked. Unorthodox and ugly but it worked, to a degree. Replacing this crap wire with even radio shack wire permanently solved the 60HZ hum problem.

I've gone a step further than your suggestion and have connected various types of interconnect to the phono input on my preamp open ended. The differences in AC injection are incredible and not surprisingly, the interconnect that was the quietest in this test reproduced the faintest instruments the best, specifically bells used in the back ground.

I'll also state it wasn't the most expensive set of interconnects that was the quietest, but at $240 a pair, I didn't buy them. The improvement wasn't $240 worth.

As for speaker wire. I spent the money there mainly for a neat install and to avoid parallel wire runs.

[soundminded]

>Interconnect wire is a different animal than speaker wire,

>and on this topic, I will attest to hearing a difference from

>the rock bottom crap wire that Heathkit provided compared to

>decent wire from Radio Shack. The main difference was not

>sonic reproduction or some other exotic paramater invented by

>the magazines. It was 60hz hum rejection.

>

>The original RCA interconnect wire was so horribly constructed

>it was location sensitive and had to be purposfully placed as

>far away from the power cords as possible. In those days, I

>went as far as to place every power cord in a braided steel

>sheath connected to ground, and this actually worked.

>Unorthodox and ugly but it worked, to a degree. Replacing this

>crap wire with even radio shack wire permanently solved the

>60HZ hum problem.

>

>I've gone a step further than your suggestion and have

>connected various types of interconnect to the phono input on

>my preamp open ended. The differences in AC injection are

>incredible and not surprisingly, the interconnect that was the

>quietest in this test reproduced the faintest instruments the

>best, specifically bells used in the back ground.

>

>I'll also state it wasn't the most expensive set of

>interconnects that was the quietest, but at $240 a pair, I

>didn't buy them. The improvement wasn't $240 worth.

>

>As for speaker wire. I spent the money there mainly for a neat

>install and to avoid parallel wire runs.

You could have gotten identical results by wrapping your interconnect wire with aluminum foil, wrapping a few turns of bare wire around the foil and connecting it to your preamplifier ground. That would save you $239.75 over buying the factory made version. BTW, that's how I shield all of my phono wires.

[rrcrain]

Soundminded,

If you took the time and read my post closely, you will note that I stated I did NOT buy the wire, the improvement wasn't worth $240.

Given the number of interconnect pairs in my system and the desire to keep the WAF at a reasonable level, the aluminum foil approach is not acceptable in my application.

Also note that I've been very careful not to claim the speaker wire I use makes a sonic difference as I'm absolutely not sure it does and IF it does, I can't hear it. What I have noted, and stated, is my amplifiers run cooler to the touch, not a bad thing. This is absolutely NOT true for all amplifiers due to differences in design.

[soundminded]

>Soundminded,

>

>If you took the time and read my post closely, you will note

>that I stated I did NOT buy the wire, the improvement wasn't

>worth $240.

>Given the number of interconnect pairs in my system and the

>desire to keep the WAF at a reasonable level, the aluminum

>foil approach is not acceptable in my application.

>

>Also note that I've been very careful not to claim the speaker

>wire I use makes a sonic difference as I'm absolutely not sure

>it does and IF it does, I can't hear it. What I have noted,

>and stated, is my amplifiers run cooler to the touch, not a

>bad thing. This is absolutely NOT true for all amplifiers due

>to differences in design.

I did read your posting carefully and I did understand that you did not buy the $240 a pair wires. Good for you, you did not waste money. I reitterate, you would get equally effective shielding from aluminum foil with a bare wire (sometimes referred to in the wire industry as a drain wire.) Many manufactured coaxial and twisted pair wires are shilded with foil exactly this way. If you don't like the way aluminum foil looks, you can cover it with plastic or cloth tape of any color you like or install it inside flexible PVC sleveing. This is NOT rocket science.