nope, all youre paying for is the name.
http://www.carsound.com/cgi-bin/ubbcgi/ ... 1;t=018285
Speaker Wire
Introduction
Wire Table
Cable Resistance Too Low?
Cable Resistance Too High?
What About Oxygen Free Wire?
What About Silver Wire?
Gordon Gow's Speaker Wire Listening Test
The Truth About Speaker Wire
Stereo Review Dares To Tell the Truth
Stereo Review Gets More Conservative
Introduction
For many years, wires that were used to connect speaker systems were often zip or line cord. The longer the run was, the heavier the wire that was used. There were no special speaker wires--just plain old copper wire--solid or stranded. The emergence of high tech speaker wire has raised some fundamental questions about the benefits of these new and sometimes extremely expensive wires.
Resistance in the speaker circuit is the key factor that determines loudspeaker performance. The loudspeaker circuit includes the connecting wire between the amplifier terminals and the speaker terminals, the amplifier internal impedance and the impedance of the speaker system. There's also contact resistance at the connecting terminals of the amplifier and speaker system.
Contact resistance with good quality connectors and the internal impedance of a good quality amplifier are normally small. The controlling factors that remain are the speaker system impedance and the speaker wire resistance.
In the early speaker manuals, starting with the XR5, I included a chart for estimating the maximum wire lengths for various sizes of copper wire needed for 4 and 8 ohm loads. I have expanded it on this page to include 2 and 6 ohm loads as well. It was based on the resistance of the speaker wire not exceeding 5% of the rated impedance of the system. The wire length is for TWO-CONDUCTOR wire. This includes one wire out to the speaker and one wire back again.
Wire Table
Maximum Wire Lengths For TWO CONDUCTOR Copper Wire
Wire Size
2 ohm load
4 ohm load
6 ohm load
8 ohm load
22 AWG
3 feet max
6 feet max
9 feet max
12 feet max
20 AWG
5 feet max
10 feet max
15 feet max
20 feet max
18 AWG
8 feet max
15 feet max
23 feet max
30 feet max
16 AWG
12 feet max
25 feet max
37 feet max
50 feet max
14 AWG
20 feet max
40 feet max
12 AWG
31 feet max
10 AWG
50 feet max
For example: you can use#18 wire for a 25 foot run to a nominal 8 ohm speaker, but if the run is increased to 35 feet, #16 wire must be used. 50 feet is the maximum recommended length for normal line cord or Romex solid copper wire. This length is more than adequate for most installations.
Cable Resistance Too Low?
What if you use wire heavier than the minimum size recommended in the table? There is no audible improvement. On the other hand, it would be a conservative choice, particularly for in-the-wall installation where you might someday be using lower impedance speakers and would need to replace the existing wire with heavier wire. Solid copper house wiring is sometimes less expensive than multi-stranded wire. Heavier wire is harder to work with, though, and that may require special connectors to fit the amplifier and speaker terminals.
Cable Resistance Too High?
What happens when the resistance gets too high? First, there is power lost in the wire and the speaker will not play as loud. More important, a larger resistance in series with the speaker makes the amplifier look more like a current source. This means the speaker response will tend to follow the rise and fall of its impedance curve. This is only to a small degree, of course, but may be more audible with some speakers than others. Speakers with small impedance variations versus frequency will be more tolerant of higher resistance in the speaker wire. On the other hand, speakers with very large dips and peaks in impedance will be much easier to notice when the wire gets too small. If the speaker has constant impedance versus frequency, the only change will be reduced output.
What about oxygen free wire?
Oddly enough, it isn't the freedom of oxygen in copper wire that makes any difference. The process of removing oxygen also removes the impurity of iron and it's this impurity that can cause the resistance to be slightly higher. The difference in resistance between copper wire and oxygen free copper wire is too small to be significant for speaker wiring. It can be considered to be ordinary copper wire as far as the recommended lengths of copper wire in the table. Oxygen free copper wire can be more expensive than ordinary copper wire.
What about silver wire?
Silver wire has lower resistance compared to the same gauge of copper wire. Smaller silver wire can be used for the same resistance. It may cost more, though.
Gordon Gow's Speaker Wire Listening Test
In the early 1980's, special speaker wires were beginning to appear on the market. Some of the claims were totally unbelievable and had prices to match. Realizing that wire resistance was the critical factor in speaker wire, Gordon Gow used a speaker cable demonstration to show there was no listening difference between these wires and plain line cord. He delivered his presentation about the truth in speaker wire using a reel of Monster cable to stand on. Fifty-foot lengths of wire were used in the comparison. Fifty feet is about the maximum recommended length for normal wires before wire inductance becomes significant at 20kHz. The setup consisted of a master control relay box and two slave relay boxes. A three-position switch was used to select one of three different speaker wires of equal length. One was line cord. The other two wires were from popular manufacturers. 8-ohm speakers were selected to be used in the test. The two other brand name wires were heavier than the line cord.
A slave box was positioned at each speaker. Power to drive the relays in each slave box was provided with separate cables. The speaker wires were switched at both the power amplifier and the speaker so that only one kind of wire was connected at a time. Short pieces of heavy wire were run from the speakers and amplifier to the boxes. No other devices were used in the speaker line. The relay contact resistance was measured to be less than 0.1 ohms.
The test proved his point. When I took the test, I was unable to hear any differences using several different 8-ohm speaker systems. BUT, when I deliberately played one particular 4-ohm speaker and I switched to the line cord position, I could hear differences. I knew this system dipped down to 2.6 ohms in one frequency range, and 3 ohms in another. It verified that differences could be heard if the wire was too light for a lower impedance system. A system this low in impedance required heavier wire. After replacing the line cord with a heavier line cord of equal length, differences could no longer be heard.
Normally, a system can run as low as 20% below rated impedance. Although many speaker systems stay within this limit, or higher, a few systems can have impedance values much lower, depending on the manufacturer. If you have doubts, it's best to ask the manufacturer about the lowest impedance of the system that you plan to use and select a connecting wire based on the lowest impedance value.
The lowest impedance limit for McIntosh speaker designs was 6.4 ohms, for a nominal 8-ohm system. The wire selection table was calculated with this in mind. Another reason was that the 8-ohm tap on McIntosh amplifiers could safely drive impedance as low as 6.4 ohms without requiring connection to the 4-ohm tap. Direct-coupled amplifiers, of course, did not have this restriction.
No person is able to establish the truth of everything for themselves. Very few people are able to make speaker impedance measurements or wire resistance measurements down to 0.1 ohms. Like many other things in life, people rely on indirect sources of information, such as sales literature, reviews and opinions. This is called Authority Belief, which is part of our belief system. An interesting article about the belief system is described in ETC: A Review Of General Semantics Sept. 1964 titled Images Of the Consumer's Mind by Milton Rokeach.
Gordon's cable demonstration provided a personal experience for customers that could replace the Authority Beliefs they had relied on earlier. The demonstration was controlled. It was an instant comparison and the listeners did not know the wire identification.
THE KIND OF WIRE MADE NO DIFFERENCE
It could be solid, stranded, copper, oxygen free copper, silver, etc.--or even "magic" wire--as long as the resistance was kept to be less than 5% of the speaker impedance. There was no listening difference as long as the wire was of adequate size.
The truth about Speaker Wire
Despite the effectiveness of the cable demonstration and the truth about speaker wire, people visiting the McIntosh room at the shows, who had not experienced the cable demonstration, were disturbed that we were using ordinary heavy zip cord instead of one of the popular brands of speaker wire. Instead of listening to the McIntosh speakers and electronics, they recalled "bad" things they had been told about "common" speaker wire and this promoted questions about the "inferior" wire being used. When we changed the wire to a popular brand of wire, customers were happy with the setup, and directed their attention to the McIntosh equipment.
The demand for high quality speaker wire was increasing and appeared to be a new marketing area for several companies. McIntosh did not make or sell speaker wire. The solution seemed very obvious--rather than spend time and effort to create negative sales for dealers who were beginning to sell speaker wire, it seemed best to encourage the speaker owner/customer to consult with the dealer about what speaker wire to use. Consequently, I no longer recommended the kind of wire or wire sizes in the speaker manuals.
By 1988, McIntosh no longer supplied audio interconnects with the electronics. Again, many kinds of special audio cables were available to the customer/owner. The dealer could also be consulted about what cables to use.
I credit the success of the speaker wire industry to their expert sales and marketing ability. However, it is my experience that ordinary copper wire, as long as it's heavy enough, is just as good as name brands.
Stereo Review Dares to Tell the Truth
A 6-page article by Laurence Greenhill titled "Speaker Cables: Can You Hear the Difference?" was published in Stereo Review magazine on August 1983. It compared Monster cable, 16-gauge wire and 24-gauge wire. The price at that time for a pair of 30-foot lengths of monster cables was $55.00. The cost for 16 gauge heavy lamp cord was $.30/foot or $18.00 and the 24 gauge "speaker wire" was $.03/foot or $1.80
"...So what do our fifty hours of testing, scoring and listening to speaker cables amount to? Only that 16-gauge lamp cord and Monster cable are indistinguishable from each other with music and seem to be superior to the 24 gauge wire commonly sold or given away as 'speaker cable.' Remember, however, that it was a measurable characteristic--higher resistance per foot--that made 24 gauge sound different from the other cables. If the cable runs were only 6 instead of 30 feet, the overall cable resistances would have been lower and our tests would probably have found no audible differences between the three cables. This project was unable to validate the sonic benefits claimed for exotic speaker cables over common 16-gauge zip cord. We can only conclude, therefore, that there is little advantage besides pride of ownership in using these thick, expensive wires"
Needless to say there was a strong letter to the editor in the October Stereo Review from Noel Lee, President of Monster Cable. "...was not the conclusion of nearly three thousand Monster Cable purchasers who participated in a warranty/response card survey in 1981-1982. Among those responding, 56 per cent indicated 'an overall significant improvement, '42 per cent attested to a 'noticeable improvement,' and only 2 per cent wrote back that they heard no difference in system performance."...
Yes, some of this claim is believable but for the wrong reasons. If the wire used previously had resistance that was too high, there would be an audible difference. If the wire connections at the amplifier or speaker were loose or corroded, installing the new cable tightly would make an audible difference.
Then we get into the more subjective evaluation. Suppose you're already using adequate size wire and have good connection at the speaker and amplifier. If you're then told the new wire will make an improvement, you will be looking for it and truly believe that you hear an improvement. Some people might go as far as saying "If I spent all that money for these cables, you can be sure I'm going to hear a difference." (rather than admit I wasted my money or have bad hearing).
There are other factors as well. If you listen to the system with the old wires and then replace them with the new ones, it could take 5 or 10 minutes to do this. By then you will have forgotten what the old sound was like. How many of the customers made an instant and more reliable comparison like what was done in Gordon Gow's demonstration or in the Stereo Review test? I wonder how the customers would fare in a test where they didn't know which wire was being used.
Stereo Review Gets More Conservative
A 5 page article by Rich Warren titled "Getting Wired" was published in Stereo Review in June 1990. It devotes 4 and a half pages to the creative claims and descriptions by the various wire manufacturers. Near the end of the article reference is made to an Audio Engineering Society paper by R. A. Greiner published in the JAES in May 1980 and titled "Amplifier-Loudspeaker Interfacing." The conclusion is that speaker cables do not behave as transmission lines, the theory subscribed to by many, if not most, esoteric cable designers.
This time the conclusion in Stereo Review was extremely conservative. Perhaps this was due to the influence of speaker wire advertisers who pay for their magazine ads. As in Gordon Gow's wire demonstration, wire sales, advertising and dealer profits were hurt by the truth about speaker wire.
"Are there real sonic differences between audio cables? We leave that up to each individual to decide. What we can say is that there are some valid reasons, described in the box on the facing page (cable pictures and manufacturer descriptions), to use good cables in your hi-fi system. Which theory you choose to subscribe to and how high a price you're willing to pay for cable comfort is up to you."
All contents are copyright © 1996-2000 by Roger Russell All rights reserved
by kronos98 » Sat May 31, 2003 3:56 pm 
