HDCD compatible?

What does this term mean? I'm looking at a cd player which is described as HDCD compatible with onboard HDCD decoders. Does this mean that it will play HDCD discs in HDCD or just play them in redbook like players that only play the redbook layer of the sacd hybrids?
High Definition Compact Disc was (is) a way to squeeze a little more information onto the digital coding on a CD. It involves slightly modifying the standard CD encoding and does not require extra layers like hybrid SACDs. The CD can be played normally through a non-HDCD player or played in HDCD if the player has the decoder to extract this extra detail. The player you are looking at will probably play HDCD discs in HDCD automatically. See if there's a switch to enable/disable. Microsoft bought the rights to HDCD six or seven years ago. Not many albums were released using HDCD; it was obsoleted in the SACD/DVD-Audio war.
I might add that you can set your windows media player to play HDCD discs as well.

Actually there were quite a number of HDCD encoded CD's released, some of which didn't stamp the HDCD logo on the jackets. I'd guess there are many times more HDCD's available than SACD and DVD-Audio discs combined.
HDCD recordings do not involve an additional layer, otherwise standard Redbook transports couldn't play them (which they can.) If a DAC, however, doesn't have the HDCD decoding chip, it just throws the extra HDCD information away and decodes it as if it was standard Redbook.

Wadia DACS, on the other hand, because of their unique algorithm software, DO look at the extra HDCD information (because thay can look at ALL the information) and so they incorporate it into the analog output signal -- and I might add, quite stunningly! (Ya jus' don' get da little logo ;--)
My cdp doesnt play HDCD but my Rotel pro decodes it, but I use my tube pre for music so the benefit of HDCD is negated by the Rotel not up to par with my Sonic Frontiers pre, I do check for HDCD and I have discs not marked wich the Rotel displays they are infact HDCD.
Actually there were quite a number of HDCD encoded CD's released, some of which didn't stamp the HDCD logo on the jackets.

Unsound, how does one find this information if it's not on the disc? Is there a code, a numeric prefix? A flag? A color? Or is it just random luck? I'd buy more cds if I could pull the gems from the junk.
When one inserts an HDCD encoded disk into an appropriate player, an HDCD light glows on the player. I guess that doesn't help much if you aren't already in the know, sorry. There used to be a website that listed most HDCD titles including some that weren't labeled as such. I wish I could remember the URL, there's a good chance it doesn't exist anymore. It might have disappeared around the same time that Microsoft bought HDCD.
Check out www.hifimusic.se/hdcd/ Click the icon for the English language version, then click on 'The Database' to get an alphabetical listing of HDCD titles.
Thanks. I've had a hdcd player for many years, but not enough damn discs to make it seem worth the money I paid. The discs sound terrific.
It should be mentioned that there are new recordings continually being released in HDCD. One reason is that many artists are not crazy about digital to begin with, and want the very best (Redbook playable) rendering of their performances.

And I'm guessing the lack of the HDCD identifier on albums will be corrected now Microsoft is handling things ;--)

Third, the HDCD process is improved, and Keith Johnson (the co-inventor of HDCD) has ressurected Reference Recordings, which has a large catalog of new releases using the ugraded process.

Thanks. The cdp I was referring to is the 5 disc marantz vc 6001. Does anyone know specifically what compatible means as it applies to this particular player? The Grateful Dead still release all their vintage live shows in HDCD and that alone is reason enough for me to need it. Thanks for all of the informed responses guys.
I happen to like HDCD and think it a big upgrade to standard redbook. Certainly I have bought new releases that still have HDCD. It's my impression that although HDCD discs are being produced, fewer players seem to contain the Pacific HDCD chip these days, which is a shame.
David, you are very right on all points. There are a few high quality units available, particularly from Mark Levinson (who BTW make their own HDCD decoding chips with permission). Then there's Wadia DACs and players which don't specifically decode the extra info, but unlike most, don't throw it away -- instead incorporating the additional data into their software decoding process. And HDCDs do sound terrific through a Wadia 27. I know, I have one ;--)
I agree it is a shame more mfg's don't support it and more labels don't produce the discs or at least make it known that they do.