Dated but still A rated DACs

Oops - just realised you are spinning cds (rather than playing files from a computer or streaming). I have only used the Convert-2 briefly for spinning cds -with an Oppo 83 and 105D with coaxial. While the Convert improved their respective sounds, playing downloaded red book files and streaming Tidal HiFi via USB is giving me much better resolution.

[Convert-2 balanced analog out to a pair of Geithain RL906 active monitors]

Ayre QB-9 DSD is still an amazing unit.  Digital doesn't get much better, and certainly not at the price point you can find a used one.

Thank you all for your recommendations... and yes, Redbook only

Redbook only..then possibly...buy a Adcom GDA-700, and have someone mod it out.

Tough to beat.

The assemblage dacs are also very hard to beat. rare. Assemblage 3.0 and 3.1. 24/96 r-2-r dacs. last of the best.

Years ago I bought a second generation Cambridge DacMagic from a dude who said he liked it but it could use a better power supply. I liked it because it had 2 SP/DIF inputs (used for cd player and streamer) and balanced outs, 3 filter options, blah blah...Soon  Audio Advisor started selling a Peter Madnick designed beefy low noise power supply called the P100 for this DAC and a couple of other things and, of course, I bought a couple of those (inexpensive). Sounds astonishingly great, or at least music going through it does. Seriously…Redbook upsampled for days (whatever upsampling 24/192 does…hard to understand as I'm not very smart), and in this case seems to work very well, and I've actually done an a/b comparison with a friend's MUCH more expensive and well regarded DAC and we agreed it was pretty much indistinguishable from his. I'm keeping the damn thing until it dies.

Weiss DAC2 or DAC202. No USB input though. Will not handle DSD but will do redbook and up to 24/192.
Firewire, optical Toslink, and S/PDIF inputs. Bal and SE output.
Both can be had under $3k used. 
Stunning built and sonic qualities.