The signal will degrade over distance but as long as you use low loss 75ohm impedance cable (like RG59 cable or the better RG6 cable) in a single run with no kinks or tight radius bends you should be fine. At the SPDIF frequency I would think there wont be much loss at all anyway.
Edit: one benefit if possible would be to fit the correct BNC sockets and plugs to the cable and equipment, this would terminate the cables correctly and minimise signal loss further.
Last edited by NRG; 14-09-2009 at 10:50.
Listening in a Foo free Zone...
Only a Sith deals in absolutes.