1 pair of good interconnects- which 2 components should I use them on?

Hi all,
I just picked up a set of 3' BlueJean LC-1 interconnects, which are much nicer than the others I currently have. Im wondering if they would be most valuable used between the phono preamp (Cambridge Azur 551p)---->tube Preamp (Cary AE-3) or should they be used to go from the Cary preamp---->McIntosh 2125 amp?

maybe this is a stupid question, but 2 fundamental things I know are that interconnects matter in the acoustic output, and also the signal output from a Cambridge phono stage vs Cary tube preamp are not the same. So with those things in mind I figured placing the interconnects in one spot vs. the other would matter based on the different output signals of each device.

I could listen to both configurations for a while and eventually gauge if I hear any difference (which probably won't be the case), but I wanted to see if there is a "right answer" first :) 

thanks for any feedback!