John Dunlavy On "Cable Nonsense"


Food for thought...

http://www.verber.com/mark/cables.html
plasmatronic
Nelson Pass measured, charted, documented and published measurable differences in speaker cables 20+ years ago. He even notes that some specific speaker cable / speaker combinations caused some "well respected" brand name amps to shut down / go into thermal overload. The same speakers and amps with different cables DID NOT act up. Obviously, the amplifier is seeing a COMPLETELY different Z ( impedance ) at it's output terminals and is simply responding accordingly. Obviously, the only variable would have been the speaker cables !!!

Besides Nelson Pass, Moncrieff of International Audio Review measured, charted and documented differences in speaker cables. He even went so far as to publish frequency response charts for many that he tested.

Due to the differences in physical layout, gauge of conductors and dielectrics used, the characteristic impedance of the cable, the total length of the cables in use, etc... the amplifier can see VERY different conditions at its' output terminals. Some cables will act as "impedance transformers" and make suitable speaker loads "unsuitable" and vice-versa. Simply altering the length of an "unsuitable" cable CAN change the feedpoint impedance that the amp sees when trying to "load up" AND alter the amount of reflected EMF that the amp has to deal with. Since Mr Dunlavy is WELL versed in RF transmission line theory, this should not be news to him.

Since this IS the case and it has been documented time and time again, you would think that he might acknowledge that the stability of the amp MIGHT come into question BEFORE making "generic" and rather BOLD statements about speaker cables being "relatively un-discernable" from each other. After all, it is well known that amps change output levels when the impedance is altered. Why couldn't their frequency response or transient characteristics be affected also ???? Those specs ARE load dependent also.

PLEASE don't get me wrong. I am not defending "the wire bandits". I think that the mass majority of this stuff is WAY overpriced. While i can understand that there is a LOT of research involved in making any REAL product, the actual costs involved in most of these "wires & cables" is phenomenally low. As such, i have bought MANY different "manufactured" cables but have also made more than a few of my own ( with pretty excellent results overall ). Like i said, i just don't like the fact that Dunlavy talks out of both sides of his mouth with a different message being heard as the situation changes. Sean
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Whoa Ezmerelda, Since scientists cannot explain all phenominon that occur, why deny the possibility of their existence. As far as these wires being overpriced and the money better spent on amplification, I am in your camp on that, if you have read my posts on wire.
Where I run into trouble with "scientific" types, is the steadfast hardheaded implication that "There exists no means by which a difference could occur sonically, so no difference can exist".
The example of plating above that I mentioned, was in my own experience as well. Here is the story. In 1990, I purchased the brilliantly engineered WELL TEMPERED Turntable and arm for use with my reference system. I had never before heard sound so correct, so right, so master tape like. It was a breakthrough in my mind. I could also discern which rooms were using this new marvel, at the shows, from the hallway!! I am not kidding. The price vs performance were so sky high, that the following year I bought another one for use with a different cartridge. I decided to remove the reference Cello MC from my current unit and put it on my newly aquired one. The two units were IDENTICAL, but the new one (1991),was about 25% better sounding in all areas. I immidiately called the factory and wanted to know what was different. "Oh nothing really, just the jacks on the termination box. They are now Cardas".
The fact is that the special copper/plating process that yields only marginal measurement changes, if barely any, was enough to change my system drastically for the better. I'm not picking a fight with you, just pointing out the truth of the subject, to MY ears, and a number of many other reliable ears that I confirm my findings with.
But I must say, regarding cable prices, I find them obsene and completely ridiculous, but their contribution to our musical present cannot be denied. I am quite certain that in actual materials, most of them could cost a fraction......Frank
Frap's post is interesting and points out a real issue.
There are two intersecting factors in his turntable story. The first is that since phono has the lowest signal levels that you are likely to find in any system, they seem to be most sensitive of all. People who use my Silver Lightning product between the turntable and the phono pre often report rather significant improvements in almost every aspect. I take it to mean that the low level signals are most likely to be effected by *anything.* The second factor is that most people have really *never* heard, or had an opportunity to hear the effect of a single, simple change (assuming it had an effect at all)! So, it is obvious that they will be very skeptical to say the least.

I had a really wierd episode with sonic effects of materials at one time, which made me really scratch my head and wonder if I wasn't hallucinating. To make it brief, I thought my big Symphony No.1 amp, one just built and being listened to for the first time, was distorting badly in both channels. I was really worried that I had made some stage on the PC board non-linear by inserting the identical wrong parts on two boards! It really sounded odd, the highs were "lifted" above the speakers, and they sounded oddly strident as well. Wrong as far as I was concerned. I am sorry to report that the problem was cured by changing the binding posts. The binding posts that were "bad" were of another manufacturer and were the standard 30 amp 5-way style, and *identical* in every visual respect to the "good" ones!

No, I did not (this is now 12 years ago) save the bad ones, and run comprehensive tests to see what the technical differences were - I wish I had. But, since the problem went away immediately, there was nothing much to think about.

If you never had this sort of experience, you'd think I was completely wacky in the head. Indeed, the experience is/was wacky, and I can not explain it. It was certainly not a mass delusion or some sort of sighted bias at work. The last thing that I wanted was to have completed an amp at 2:00 in the morning, and have to trouble shoot it because it sounded like dog meat.

So, there are those who have had these sorts of things happen, and those who have not. Some of the have nots simply don't have gear that would permit them to discern what was going on (like if your amp has those brand binding posts on it all the time! :- ) ) or simply have just never been in a situation where it simply HAPPENS. They, with good reason, tend to be very skeptical about these reports. I understand.

_-_-bear
I had great difficulty in blending bass and midrange in my admittedly complex system. I got most of it right by experimenting with speaker placement and room treatment but the final touches on bass rendering were only achieved by finding the right interconnect and speaker cables. I don't care if its against the law of physics or if I am hallucinating as long as my ears keep on telling me, that it sounds right now. As Greg so aptly put it: Cables are both personal and system dependent!
Geez...

It's hard to follow threads on a non-threaded heirachy site!

Anyhow JHunter suggested the pink noise method for testing cable "differences." I certainly do like to use pink noise for discerning very small effects. You can use pink noise when tweaking a crossover, change a *very small* resistor value and *hear* a change. You can forget about hearing the change using any sort of music.

So, does it matter if you can't hear the change when using music? You bet! The resulting sound when the improvments have been made are almost always subjectively better sounding and most often objectively test better with test equipment.

this is a follow up to Jhunters post back 5-31-01

sorry for the delay! :- )

_-_-bear