What makes a Cd player a Great cd player

Arcam FMJ-CD23 was great because of use of DCS licensed RING-DACS (rotating its divider components to get accurate average value). They had problems with production yield of DAC chips and stopped using them. Next model had regular DACs. I've never heard this player but judging from reviews it is great bargain - good sounding and solidly built.

So in this case sophisticated DAC ICs (used by DCS in very expensive DACs) make this great CD player.

Wow, didn't realize the DCS DAC architecture could be had for that price! I'd jump on that deal if the Arcam sounds anything like the DCS gear I have heard!

Mapman - I could be wrong about reason (production yield) - look here: http://forum.audiogon.com/cgi-bin/fr.pl?ddgtl&1186749514

The main problem with DACs is how to get better than 16 bit linearity. Most you can get in traditional architecture is around 18 bit. Sigma_Delta DACs can deliver much better linearity but it is only in specifications. Fast Sigma-Delta has timing issues (inaccuracies)that effectively translate to noise and limit resolution perhaps to the same 18 bits. Ring-Dac allows to get a little more by rotating components to get accurate dithered average current on the output of the DAC. Original CD data is only 16-bit but digital filtering increases resolution.

Yes, the ring dac architecture for applying dither from what I have read strikes me as a very practical way to achieve higher resolution yet retain a smooth response and full dynamic range. When I've heard the DCS gear, what my ears heard was consistent with what I would expect having investigated the technology in more detail a bit later after the fact.

That DCS sourced system produced some of the most natural sounding massed orchestral strings I have ever heard from a CD source. I attribute at least part of that to the unique Ring DAC design.