what do I upgrade?


Current system
wadia 302
marantz vc 5400
krell showcase pre/pro
krell kav 3250
adcom 5400
wilson sophia
wilson cub II(as center)
snell sr30 surround speakers
all nordost red dawn cables

System originally started as HT but I want to improve on the 2 channel side. What would be optimal path in upgrade? Should I start in pre amp or upgrade amp? What models should I be looking into?

Thank you in advance for your advice.

allenc
I just ran dedicated circuits today along with Albert Porter's ports and am so happy. I was replacing 60 year old stuff so I expect an improvement but still find the amount of improvement completely amazing. The heightened palpable quality, real presence and low level detail. I find the midrange fuller and the bass tighter all with a sense of the music being more simple and clean.

I will find out in a few weeks how they really sound after everything has settled down but if they get even better it will be the cheapest tweek ever...
How do you compare the cub as a center channel against others that you can try at home? I have a pair of watt/puppy 6 and aerial cc5 as a center but I want to exchange the aerial for one cub trying to match as close as possible the "wilson sound"; my surrounds are Aerial also(Im VERY happy with them)but they are not so critical in HT sound. Thanks