Any of the Resolution Audio CDPs (CD-50, CD-55, Opus 21).
Alternately, a pair of EVS attenuators. These have both a male/female RCA. Plug the male end into your amps inputs and the cables from any CDPs output RCAs to the inputs of the attenuators.
http://www.tweakaudio.com/Ultimate%20Attenuators.html
Alternately, a pair of EVS attenuators. These have both a male/female RCA. Plug the male end into your amps inputs and the cables from any CDPs output RCAs to the inputs of the attenuators.
http://www.tweakaudio.com/Ultimate%20Attenuators.html