This player may not be up your alley, but have you taken a look at the Cary 306/200. With this player, you have the option of playing your HDCD discs through the Pacific Microsonics PMD-200 HDCD digital filter, or you can bipass the filter and upsample the discs to 24/192 instead. I'm not sure if there are DAC's or other players that have similar operations.
The following review of the 306/200 explains this process more specifically:
http://www.positive-feedback.com/Issue2/cary306.htm
The following review of the 306/200 explains this process more specifically:
http://www.positive-feedback.com/Issue2/cary306.htm