For "Bit Perfect" conversion of PCM you need a dac that has R2R Ladder Multibit D/A converters. The better implemented the better the sound. many top dac are going back this way again.
EG: If you can afford them just some of the top ones
Trinity Dac
Ypsilon Cdt-100
Phasure
MSB Platinum
Total Dac
Audial (Peja Rodgic)
AMR top dac and cdp (Thorsten Loschec)
DaVinci Light Harmonic
Exasound
Reimyo
CH precision
EC Designs
Forget Delta Sigma based dacs, (bitstream,1 bit,Sabre ect) they just don't do PCM (RedBook cd,DVD-A,DXD.) like a R2R Multibit d/a converter can.
Cheers George