There's currently a track off of the PC Engine/Turbo Duo CD game "Dracula X" that I would like to get ("Poison Mind", for any of you CV music afficionados); however, the track is so small that it's not a CD track--like most of the other ones that can actually be heard if put into a CD player--but a track within the game data itself. I'm positive of this, both because I cannot find it anywhere in the easily ripable tracks, and because it will play at the final stage and at boss battles regardless of whether or not I have Hugo correctly playing audio tracks.

The most annoying thing is that the track probably isn't any longer than seven seconds (but man can it loop), so it doesn't seem likely that I'll be able to find it. But, assuming I can, how would I go about extracting it?

It's probably ADPCM data. I haven't really looked at the non-music track sounds, but Death's dialogue in Stage 0 is ADPCM data and it's played via the BIOS AD Play functions.

I don't know anything about converting ADPCM data into WAV format or anything, but it can probably be done. I'm not sure how you'd go about finding the data without trapping the calls to AD_WRITE and figuring out where the data is being pulled from. I think it's AD_WRITE. It's been a hwile since I've looked at Dracula X, and I don't remember for certain whether or not it's AD_WRITE  or AD_TRANS that's used to upload the data.

Or you could just read what Rich wrote while I was typing this.