Can speaker cables be too thick?

The question is not whether one can hear differences between cables: this subject has been discussed so many times. The question is: do we need very thick copper cables (that is the conductor, not the insulation) for proper transmission of signal, because according to a well respected Swiss manufacturer..., etc. And if one is using "too" thick speaker cables, let's say 4 AWG or thicker, would that give negative impact to the sound? According to Muralman thick speaker cables do have negative impact on his system, but he didn't specify what is getting worse. What is relevant here is not the total speaker cable size due to insulation (it might be as thick as a wrist) but the cross sectional area of the (copper) conductors. Have any of you used 4 AWG or thicker speaker cables btw?

Chris

I would like to add my two cents, for anyone that's interested.
First, the impedance of the cable and amplifier combination (resistance plus inductance and capacitance) needs to be low relative to the speaker to maintain control - this establishes damping factor.
The resistance of the cable, which is a factor of the wire gauge, will affect the voltage/power of the signal to the speaker. The effect however, is constant for all frequencies, so it affects overall loudness but does not roll off the sound at either frequency extreme.
Next is the capacitance and inductance of the cable. In my experience, cable capacitance is not really a factor at audio frequencies, but inductance is. The inductance of a cable resists the flow of current through it, thus affecting the ability of the cable to pass high frequency transients and affecting the sound. Therefore, cables with lower series inductance will pass the musical signal more faithfully. If you look at Shadorne's link you'll see that it supports this.
I do listen to cables, and my experience has supported my conclusions.
It's unfortunate, but I think if more cable manufacturers published the electrical parameters of their products, more people would be able to associate the differences they hear with the electrical properties and much of what appears to be cable snakeoil would disappear.
This is just my opinion, based on my knowledge and experience, but it does drive the decisions I make when I select audio parts and components, and I am very satisfied with the results I've achieved. :o)

Just to confuse things further, I've found that changing power cords and related power-related "components" -- outlet/receptacles, conditioners, IEC/AC connectors, even fuses -- makes more difference in my system than speaker cables do. More than interconnects and substantially more than speaker cables. Two years ago I would have thought this to be COMPLETELY crazy. FWIW. Dave

Oh, I didn't know the copper conductor was the issue. When Dazdax mentions Cardas and MIT in the same line, I naturally thought he was talking about the visual size.

I do not have an opinion on thick cables. I will try that on my bass panels. I found very thin works wonders on the mids and highs.