Speaker cable gauge and amplifier power


Based on my limited understanding of electricity, sending electricity through a wire is like sending water through a pipe. Using a larger cable gauge or bi-wiring will increase the amount of current required from the amplifier.

It seems like there must be a way to optimize speaker cable gauge and length based on an amp's current and watt ratings. Lower powered amps would mate best with narrower gauge speaker wire, and a powerful amp would benefit from thicker wire.

Am I oversimplifying, or are there established guidelines based on calculations of current, capacitance, etc.?
jpbach
One thing that I found interesting is the wire guage used INSIDE speakers from the terminals to the drivers. We hook up our 8-ga hoses to speakers that use 16 or even 18-ga internally. This renders anything larger before it moot. So unless you need 25-plus ft of speaker cable, then the issue of voltage drop (not current delivery, BTW) should not be a factor in the size of the speaker cable.
The resistance of a conductor depends on the length use and the cross sectional area. More precisely, it is computed this way: R=p(l/a)
p=resistivity of the material(ie. a constant for copper, silver, etc.)
l=length
a=cross sectional area

In theory, if the length is short and the cross sectional area is large, the resistance comes out low.

In audio, the response of the resistance value of speaker cables are greatly enhanced, reduced, or in general influenced by the interaction of their characteristic impedance(because we are talking AC) to that of the passive crossover use which can result in either purely resistive (preferable), inductive, or capacitive in nature.

IMO, this is the reason why we hear difference in wires and nothing else. Unless of course you can teach electrons where to go and what to avoid.

In the end, no one can tell you what will suit your ears better. If measurements is the bread and butter, then the shorter the wire and the bigger the cross sectional area the lower the resistance of a wire which leaves the cable electrical parameters negligible and the speaker crossover to be the one who dictates the nature of the impedance seen by the amp.
Here is my opinion on this.....as Albert Porter said, the gauge of most speaker wire is overkill - strictly considering the insulation breakdown point. I other words, 16 awg wire can easily pass 15 amps of current without melting the insulation and causing a short or even a fire. However, from an audio perspective, wire needs to pass a lot of transient signals to sound good (fast, short-term power demands). I my experience I have found that the series inductance of the wire has the most influence on sound. Inductance resists current flow, so wires with lower series inductance values will pass short-term, transient signals better, resulting in better sound. That said, I agree that the results should be audible, which is the ultimate test of any component. :o)
If you believe "pipe size" is that important, giving a cable like Audience AU-24 Speaker cables a spin can be very surprising. I used them with a Pass X-250 driving Revels for a couple of years and STILL remember my shock at how they outperformed the garden hoses I was using at the time.

It's like Albert said- MANY factors go into cable design.