Super Castlevania 4? Still has the best soundtrack (not without hefty competition mind you) of all the CV games in my opinion.
That type of CV game has unfortunately fallen by the wayside over the years, replaced with the Symphony of the Night style (metroidvania) template.
Those are still great despite being different, so if you have a means to play SOTN, or any of the GBA & DS games, definitely recommended!
Particularly because now, that style of game isn't being made anymore either, since they moved the series away from the creators in Japan.