whats a good older hdcd cd player?

FMJ-23 used RINGDACs same Dacs used in expensive Elgar. (ARCAM got license for them). Because of production problems (low yield) they switched to regular DACs in next generation. Get one if you still can. Ringdac has 4 current sources built-in that randomly add noise (16 levels)to increase resolution in filtering. As for HDCD - it is 16-bit compressed format where least significant bit 16 switches dynamic range od remaining 15 bits. Some studio engineers say that it sounds weird and was introduced to promote media with very strong copy protection. I would stay away - it's dead format.

Another vote for the Rotel RCD-971. I've put it up against many players costing many multiples of its price. Never once was it embarrassed.

As said before, you can't beat the Arcam 23T. I've held onto one even though I have the AudioAero Capitole. The HDCD's sound great on it. In fact, a friend just purchased a sealed left-over 23T for $1100.

Arcam dv27. The HDCD performance is great. I mean really great. It's a big difference compare to when playing non-HDCD disc. Everything just comes out more lively; deep bass gets deeper and even image gets sharper. Used can be had for less than $500. Whereas, I've tried the same test on a Linn Genki and the sound was pretty lame. No big difference between playing HDCD or non-HDCD.