DAC is one place where price has nothing to do with sound quality. See if you can find out which DAC chip they use, as all DAC using the same chip sounds alike.
Looks like Del Canto uses PCM1796, which is a 6bit R2R + rest Delta Sigma. This chip sounds pretty nice. Ross Martin Audio would be a budget choice if you like the sound of this chip.
Looks like that Marantz uses CS4398, I have never heard of this chip so I can't comment. "multibit Delta-Sigma" so looks like it'll have similar sound to PCM1796, see if you can find out how many bits R2R it is, more bits sounds better.
Looks like Del Canto uses PCM1796, which is a 6bit R2R + rest Delta Sigma. This chip sounds pretty nice. Ross Martin Audio would be a budget choice if you like the sound of this chip.
Looks like that Marantz uses CS4398, I have never heard of this chip so I can't comment. "multibit Delta-Sigma" so looks like it'll have similar sound to PCM1796, see if you can find out how many bits R2R it is, more bits sounds better.