Uhh... if the cables are only going to be 1/2 meter can't you just get a cdp with one set of volume controlled outs and use splitter 'Y' cable to the amps???
"halves the input impedance" True, but should be ok with reasonable amps and cd players and a short cable.
"halves the input impedance" True, but should be ok with reasonable amps and cd players and a short cable.