HDCD compatible?

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 ;--)
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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.

www.referencerecordings.com
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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 ;--)
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