Do materials alter frequencies and speed?

Frequencies and speed is not accurate to describe the effect. Geometries aside (spacings and wire gauge etc) , materials in cables have several effects, both insulation and metals. Lets start with metals:

The crystal lattice in the metal can cause reflections in the cable, because they are impedance discontinuities. These occur at very high frequencies, but this does not mean that they will not become audible. Depends on whether the driver reacts to these reflections or not. most of the time, this is audible and sounds like sibilance on top of the high-frequency information in the music. Metal purity, choice of metals, cryo treatment and other factors affect this.

The insulation has several effects as well. Besides the obvious effect on capacitance per unit length, the dielectric material absorbs charge and releases it when transients occur. Depending on the material, it is not completely released either. In general, if the time-constant of the material release is slower than the time-constant of the transient, smearing will occur. Dielectrics with a lot of air will usually have the least dielectric absorption effect. The effect of this is usually a loss of HF dynamics, often described as a roll-off, but technically it isn't.

>>most of the time, this is audible and sounds like sibilance on top of the high-frequency information in the music. Metal purity, choice of metals, cryo treatment and other factors affect this.<<

This is what I mean by myths and wive's tales. I predict no hard evidence will be offered to back the idea that any of this is true.

>>the dielectric material absorbs charge and releases it when transients occur.<<

Sounds like advertising from a cable site -- this has been debunked.

>>smearing will occur.<<

No one has ever been able to measure audible distortion caused by a speaker cable. No one. Zip, zilch, null set.

>>The effect of this is usually a loss of HF dynamics, often described as a roll-off, but technically it isn't.<<

This ought to be measurable. I predict we will not get any back-up for this, either. No way to quantify the loss of dynamics, no double blind listening tests to see if anyone can hear any such thing.

Basically, in the audio world, you can say anything you want about cables because standard of proof is completely absent. So people run around saying whatever they want, throw a few big words in there for good effect, people repeat it and pretty soon, you've got another urban audio myth -- and possibly another cable sale.

From Audioholics Web-site ----

Dielectric Absorption in Cables Debunked

Before we debate the relevancy of Dielectric Absorption relating to speaker cables, and commonly perpetuated by many exotic cable vendors and cable cult hobbyists, let us first define the roll of a dielectric.

According to Wikipedia (http://en.wikipedia.org/wiki/Dielectric) the definition a Dielectric material is an insulator. The ideal dielectric would be a vacuum or infinite impedance. However, real world dielectrics do NOT have infinite impedance and therefore are not perfect. As frequency increases, the Dielectric starts exhibiting shunt resistive losses which can be measured and quantified as signal loss across the termination load. Fortunately for our application (audio) these shunt losses don't begin to surface until frequencies much higher than the audio bandwidth.

At audio frequencies, even the worst dielectrics (IE. Polyvinyl Chloride, aka. PVC / plastic) used in cheap and many exotic speaker cables maintain shunt resistive impedances in the mega ohms or more. When dealing with a low termination impedance of a loudspeakers (usually in the order of several ohms) the dielectric shunt resistance is on the order of 10^6 greater, thus the parallel impedance remains virtually unaffected and we see no losses due to the dielectric at audio frequencies.

Cont'd....

http://www.audioholics.com/techtips/audioprinciples/interconnects/dielectricabsorptioncables.php

Perhaps this one of the reasons the 10 guage Zip Cord exhibits lower Capacitance and Inductance than many of the more expensive speaker cables in the chart referenced above and why none of the more expensive cables produce a more linear frequency response over the audio band.

Rsbeck: We've been through this before. The test results published for frequency response do not take into account impedance variations whatsoever.

As i've posted before based on figures extrapolated from the data that they provided, "zip cord" can introduce very measurable treble roll-off starting within the upper midrange / lower treble region on some speakers. Your refusal to see or acknowledge this potential problem, yet quote the same crap over and over again, makes me question your agenda.

The fact that you keep promoting zip cord yet chose other wires to run in your own system speaks volumes in itself. Make us proud and put your money where your mouth is. Doing so and selling your "fancy cabling" will buy you another couple of discs and tell us that you really do believe what you post. Saying one thing and doing something completely different doesn't set much of an example, nor will it sway anybody to believe what you are promoting. Once you swap those cables out of your system, you can keep telling yourself that it sounds exactly the same and that you are happy with your decision. Sean
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