Well Castlevania hasn't ever really had a distinctive sound. I mean, you had the upbeat "halloween-esque' tunes from the first game, the darker baroque stuff from the second, SCIV's downbeat and ambient music, Rondo's very very 90's synth pop, CV64's slow ambient stuff, Harmony's experimental music...
Even Yamane mixed things up. SotN and Aria had orchestral rock and classical music, Lament had an operatic sound mixed with pop music, Curse had a more heavy metal sound mixed with electronic music, PoR was upbeat and arcade-y, and OoE was a sort of hodgepodge of pop, classical, symphonic rock, and even some SCIV-style stuff (Jaws of a Scorched Earth sounds like it could be an alternate track to SCIV's sunken ruins stage.)