Do materials alter frequencies and speed?

Sean -- sorry, buddy, but you know I don't care about your "roll-
off" that happens outside the range of audibility so it doesn't matter
how many times you bring it up, it ain't like fine wine and it doesn't get any
better with age.

In fact, it is the exact kind of half-truth I am talking about.

I challenge you to present the facts honestly and do not leave anything out.
Every time you talk about this "roll-off," I challenge you to post
the truth -- that it is outside the range of audibility. I think that is a pretty
important point.

I posted a reference to a whole chart of cables I do not own, but I am not
allowed to mention the Zip Cord listing? Not allowed to say anything good
about Zip Cord? Who made that rule? You?

Finally, next time, don't just reference what YOU wrote last time -- try to
recall what *I* tell you each time you bring up the bogus "roll-off" -- that
way, you can expect me to have the same answer as before.

Save us both time.

Rsbeck - you can see plots of measured and computer simulated response of ZIP cord versus my speaker cables at this website:
http://www.empiricalaudio.com/frclarity7_electrical_performance.html

The simulated and measured are both obviously rolling-off with ZIP and have different phase response. The only issue is whether this is audible or not, and based on my listening tests, it is. My cables must be doing something right as they were favorably reviewed in April Sterophile, and I might add that I have never put any ads in Stereophile.

Steve N.
Empirical Audio
Manufacturer

>>The only issue is whether this is audible or not,<<

I appreciate this bit of honesty -- you seldom see this mentioned.

The graph on your web-site confirms that this "roll-off" happens waaaaay
outside the range of audibility.

If you have DBT or ABX listening tests to back up your claim that people can
hear this, I would be most interested in seeing that data because it would
shock the scientific world.

I also appreciate that you've identified yourself as a cable manufacturer.

I suspect there are many people in cable sales who frequent sites such as this
and do not identify themselves as such.

Some reality ---

The psycho-acoustic data shows that for pure tones at 16kHz the smallest average detectable difference in level is 3.05 dB. The findings were based on individuals 20 to 24 years old that had normal hearing to 20 kHz.

"Speaker cables: Measurements Vs Psycho-acoustic data," Audio, July 1994

Rsbeck: The measurements that you initially referenced showed roll-off starting at appr 22 KHz if i remember correctly. This frequency is based on an 8 ohm load. Using a 4 ohm load, roll-off would occur at half that frequency i.e. 11 khz. At a 2 ohm load, roll-off would occur at appr 5.5 KHz. With a 1 ohm load, roll-off would occur at appr 2.75 KHz.

Given that impedance varies with frequency on most every speaker known to man, the associated roll-off's and phase shifts are quite audible when one has both good listening ability and a reasonably transparent system. It should be noted that there is a BIG difference between having "good hearing" and being a "good listener". For the record, i have several sets of speakers that drop below 2 ohms, hence my concern over such matters.


Obviously, the zip cord only works "acceptably" with a theoretically non-reactive speaker that maintains an impedance of 8 ohms or higher. It should also be noted that not all zip cord is of the same inductance level or nominal impedance, so these figures are based on best case scenarios. As length of the cabling is increased and / or the inductance climbs higher, the effects will become even more pronounced and severe in amplitude. The fact that the nominal impedance of the cable is 100 ohms or more, and will negatively effect power transfer characteristics from the amp to the speaker, is true regardless of the length used.

As to what you've told me, i forgot all of that. If it was true or factual in the least, i would remember it. You keep painting pictures but you leave out the most important details i.e. the ones that discredit your point of view and the message that you are trying to promote. The fact that i've refuted your past arguments using your own reference materials shows that those you rely on to do your homework for you also paint "half pictures".

Like i said, put your money where your mouth is. If zip cord works as well as you've said, you'll hear no difference, can continue to enjoy your system as you know it and can actually put a few dollars in your pocket from the sales of the "snake oil" cables that you're currently using. Until you actually do as you suggest that others do, you will be thought of as the boy who cried wolf. Over and over again. Sean
>

PS... Nelson Pass demonstrated that different cables affect power transfer, transient response and even the ability to make or break a system in terms of operating or shutting down simply by changing speaker cabling. He did so 25+ years ago and that evidence is still posted today. The fact that Nelson does not market ANY type of cabling and only did this because of the differences in how amplifiers were responding to specific loads doesn't seem to phase those that wish to promote a specific agenda i.e. that such things can and do alter what we hear and how the system responds.