Need opinions on boxing a dual mono line stage

[phrarod]

I'm wrapping up my year and half pre-amp design and now I need to think about the casing.

I decided to go completely dual mono with separate PTs and ground planes for each channel.

Several people suggested I make a two box set up with the supplies in a separate box. What concerns me about that is I did this with my dac project and the shorter the umbilical cord got the better it sounded. I'm thinking DC doesn't like long runs.

In the past I've put the final PSU cap inside the amp box thinking this would help but I'm not sure.

Otherwise I can just make one chassis with shield around the supplies.

Any thoughts by experts much appreciated.