Which cable has most impact - IC, Spkr., power?

Definitely depends on the compatability of the equipment/cable link and the synergy between all of the equipment and cables. If you cannot establish a synergy between all of the cables, you will be changing cables frequently. Some people decide to change the equipment instead. I would focus on upgrading your speaker cables and build around them. If you build around the interconnects, it can be a lot more expensive to constantly be changing speaker cables. For me, speaker cables made the biggest noticeable change, which I feel also reduces the amount of noticeable change derived from the interconnects and power cables.

IMO, start with the power cable.

Joc3021,

You are making the mistake of attributing properties to ordinary wires. It is the quality of AC power and the choice of components which determine whether a cable will make either a large or negligible difference.

Think about it;
Poorly designed power supply => Power cord makes a difference
Extremely Dirty AC power => Power cord makes a difference
Poorly matched impedances between components => IC's make a difference
Ground Loops due to poor grounding or leaky power supplies => IC's make a difference
Speaker load extremely low impedance and highly reactive => Speaker cable makes a difference
Amplifier Output Impedance extremely high => Speaker cable makes a difference.
Unstable Power Amplifier => Speaker cable makes a difference
Underpowered poorly designed outputs stage of the Preamp => Interconnect cable and length can make a difference
Jittery Digital signal poor jitter handling/rejection => Digital Interconnect and length makes a difference

If you follow the logic you will understand that any cable anywhere in your system can make a difference but it isn't a specific property to the bits of wire but really has much more to do with the setup and components themselves.

So exactly the same cable/power cord/IC can make no difference in one system and a huge difference in another...

04-04-09: Jmcgrogan2
This is a common topic in these forums, and one with no absolute answer.

04-06-09: Joc3021
As the thread originator.....I'm still searching for an answer. Maybe this question is so system dependent that there is no definitive right answer, but it seems to me there should be.

I hate to say I told you so.......but I told you so. As in almost all audio related questions, there is no definitive answer. Probably because this whole hobby is so subjective.
If you're looking for definitive answers, you're in the wrong hobby. Don't bother with wine's, scotch's, or food either, as they also are all personal tastes related.

Try astronomy or physics as a hobby....you'll find more definitive answers.

Cheers,
John

I would think IC to source equipment would make the most differace BUT not if all your other cables were of low quality. Then I would think any one of them.