[sdiy] Converting rack mount to DC input?

[cheater cheater]

Hi all,
Beside my head I have my mic processing rack with a bunch of preamps,
voice strips, EQs, etc. I'm in a very quiet room, and the transformer
buzz is audible, which is undesirable for my kind of work. I've been
wondering if anyone ever tried converting their analog racks to DC
input, and how that went. All the racks I'm talking about are
internally running at +15,0,-15V rails, so I could just have a single
linear (or even high quality SMPS) power supply, distribute it via XT
or XLR style connectors, and have simple filter boards inside each
unit that filter the incoming DC, with switch to disconnect the mains
PSU and connect the DC board. I was wondering if this is a good idea
in general and in particular how this relates to issues like ground
loops and EMI pickup. My run from the DC power supply to the rack
would be about 2-3 meters long, but it would be running parallel to
some digital cabling. I would also be interested in suggestions on
connectors to use, especially if I want to make daisy chain cables
that go from device to device.

I would appreciate suggestions / experiences on the topic.

Thanks!