Best CD player under $500 used?

I like Sugarbrie's suggestion for a used CD6 and a power cord upgrade. The CD4-CD4a-CD6 series was good value for the money.

I also like the Shanling CD-S100 / Music Hall CD25 player. You can get it new for under $500 and it will sound better than a great many older players selling used at that price.

I agree with foreverhifi. I've been using an RCA5223P DVD player with a 24/96 DAC for the past few years after a serious comparison revealed it was better than my Arcam Alpha 8SE, which I sold. The RCA, from what I understand, is a re-badged Panasonic (has a headphone jack I've never used, volume control, etc.) and with some basic tweaks has been a very good performer.

The player I'd look at today is the Philips 963SA, available for under $400. I've had e-mail correspondence with someone who owns one who says it is substantially better than his Sony SCD 777ES on redbook and better (with the 192 upsampling on) than a Muse 296 DAC (rated Class A by Stereophile) that he also owns. Plus it does SACD and is a DVD player as well.

I'm not sure what sort of electronics you are going to use your CD player with; but would highly recommend the Music Hall MMF CD-25 CD player. Unlike a number of the other units mentiones above; this is a current model CD player. Has decent build quality, provides very smooth yet detailed sound (which improves with time) right out of the box, has HDCD decoding, and operates very quietly. With a little shopping here on Audiogon, you should be able to get a demo unit or a little used unit in your price range.
Also, when you get a chance - upgrade the stock power cord. It improves the already decent sound even a bit more. I did so a week ago and am delighted that I did so.

How about a NEW NAD C541i for $400?

HDM, would you recommend a DAC with the Philips, and, if so, what would you recommend?

Thanks