Recommendations for used CD player


I'm looking to improve my sound by adding a CD player to my system.  I'm currently now just using a Yamaha DVD player along with a Yamaha Aventage home theater receiver (which uses ESS Technology ES9006 SABRE DACs).  I use the receiver as a pre/pro with a Threshold S500/II amp and B&W 802 Series 2 speakers.

Right now I really like my sound and I've read these DACs are fairly high quality, but wasn't sure if I could get improved sound by adding a used, higher end CD player and possibly outboard DAC.

No SACD needed, my budget is about $400-500.

Thanks.

dastro
I just purchased a new Cambridge CXC Redbook CD transport for a headphone system new for $400.00 and am very satisfied with it check these out for a new solution as apposed to used.
To improve the sound I would look into an external dac and a low cost cd player for a digital transport.  To complement your ESS dacs, look for something that has Burr Brown or AKM dacs that way you can have a variety because each has their own sound signature.  
An external DAC will provide better SQ than a receiver's built-in unit. A home theater receiver contains a preamp, amp, a shared power supply, circuitry for multiple channels and functions, and oh yes, a DAC.

The design of a dedicated DAC unit is more than just a dac chip, it will provide better jitter reduction, a quality power supply, and an analogue output stage which provides tonal characteristics superior to that of a receiver.
There are multiple inputs for CD, computer audio, streaming and accepts many different sample rates. A DAC in the $500 to $1000 range would take your Yamaha DVD player to a higher level in sonics.
I agree that an external DAC would be the way to go. Use the DVD player as transport. There is a SCHiit Bitfrost w/uber analog upgrade for sale here on AG, $290 I believe. Since you don't require USB input, you could search for an older very high quality DAC which could be purchased for a fraction of the original cost.