Whats more important, source cables or amp cables?

Since you already have the cables, why don't you try them out and see which way you like better?

IMO there is unfortunately no way to predict the answer to your question, in part because there are many component-dependent variables that will influence the behavior of the cables in each location. A couple of examples, among many, being the output impedances of the components, and the susceptibility of the components to ground loop effects. A "better" cable will not necessarily provide better performance in any given location, depending on how its characteristics interact with the characteristics of what it is connecting. Also, "better" performance is not always subjectively preferable.

In your specific case, though, your connections are balanced, and I suspect that the components have low output impedances. Those two factors will in general tend to reduce cable effects, everything else being equal. So the answer MIGHT be that it won't make a lot of difference either way.

Disclaimer: There are those who believe that being further upstream (closest to the source) increases the importance of the quality of a cable or component. I do not subscribe to that philosophy, my philosophy simply being that a chain is as strong as its weakest link, regardless of where that link is located.

Regards,
-- Al

Al, I have read the same as your disclaimer for hours last night, and I tend to agree with you... The weakest link should rear it's ugly head, luckily a Serenade isn't a 25 dollar Monster cable, so although it's not as good as the Crescendo, its only a notch down.

Im just not sure where to place them for best effect. I guess unless someone has some experience with a similar system, and its too subjective at this point, there isn't much to do besides swap them in and out. I also read though that some cables can take time to recover, so A/B/A isnt the best unless I want to let it play for a day or two between sampling. I will eventually get another pair of Crescendos when I can find a deal on them, but until then Id like to maximize what I have invested.

Hope your ready for a slew of different answers. IME in two different Mcintosh systems with a least 3 different CDPs the pre to amp made the most improvement when using the better IC between the two. It is contrary to logic as one would think the source is the start of the chain and most vulnerable to IC changes. All I can conclude is that a source is a stronger signal than the preamp signal which is at a lower variable signal. If running at very high or full gain maybe it would be a different outcome, but who would want to.