Do materials alter frequencies and speed?

>>the broadest spectrum be derived from the use of all three?<<

Are you looking for the broadest spectrum? Or, the flattest response over the audio spectrum?

Are you talking about at audio frequencies?

You can get flat signal response within the range of audibility with the use of copper. Silver has slightly less resistance, but you can overcome that with the use of thicker gauge copper. No one has ever proven that silver has a sonic signature. Never seen a study that shows people can identify a silver cable versus copper in a DBT or ABX as long as they are precisely level matched.

Here's a chart comparing resistance, inductance, and capacitance between several popular cables -- you might be surprised to see which cables have the highest capacitance.

http://www.audioholics.com/techtips/audioprinciples/interconnects/speakercablereviewsfaceoff7.php

Gregm is right. Dynamics involves several things - not just dynamic range which is noise floor related. I was referring to slew rates but typically, cables have less impact on slew than p-n junctions and circuit bandwidth so the point is academic.

I took "combination" to mean configuration. It is meaningless to talk about just the materials since their configuration plays a significantly larger role than material resistivity alone.

"At what point does an increase in inductance and capacitance cause an audible impact on dynamics?"

No one knows for sure - there are simply too many variables.

Arthur

My perception of the impedance issues which have been brought up seems at least partially corollary...
Source components have unique reactive impedance characteristics comprised of a resistive component, an inductive component, a capacitive component. Terminating (load) components also have these characteristics although they typically don't match the source component's reactive signature. Then add the connecting cables' complex impedance (which is yet again different from source & load reactive component) into this complex impedance network. The source impedance doesn't match the load impedance, & the transmission line impedance matches neither.
These mismatches are a guaranteed formula for signal-reflections which result in standing waves. Propagation delay of various frequencies within the bandpass differs significantly. The result is a smearing of the signal throughout the transmission process of simply coupling a waveform from one box of components to the next box.
Considering the radically varying complex-impedance network of everyone's own unique combination of audio componentry & interconnecting cables, it's not too hard to understand why (obvious differences aside) no two rigs sound quite alike, and why a cable moved from one system to another system can sound so very different.

My impression is that people like to throw myths and wive's tales together
with things that are half-true and extrapolate from that into the land of the
hypothetical based on hypothetical on top of wishful thinking.

I had a strong feeling that no one was going to be able to tell me anything
solid about this affect on dynamics, how it is measured, or if there is anything
to back any of this.

What isn't in dispute in this discussion is that it is desirable to have low
capacitance and inductance. But, we also know that several very expensive
cables exhibit far higher inductance and capacitance than 10 guage Zip Cord
(See table referenced above). If there *was* any solid proof that higher
capacitance and inductance -- at the levels exhibited by these expensive
cables -- degrade the performance of these cables with regard to dynamics
-- that would be interesting. Especially, perhaps, to the owners of those
cables. But, since there apparently isn't anything solid, "No one
knows for sure -- there are a lot of variables." We don't really have
anything.

Yes, we do know that the configuration matters most if one is attempting to
manipulate inductance and capacitance, but this just supports the counter-
point that materials -- silver versus copper -- matters least. And that's the
answer to the original question. If capacitance, resistance, and inductance
matter most with regard to dynamics, a whole lot of expensive speaker cables
do not measure as well as 10 guage Zip Cord (see table referenced above) nor
do they provide more linear frequency response (see frequency response
charts included in referenced article).