In Soul Reaver, one of the levels was The Silenced Cathedral. It had been built as a holy weapon against vampires, with a massive steam-powered organ built into it that would have blasted out holy music at incredible volume, powerful enough to kill the vampires infesting the world.

Instead, the vampires overran it, and a swarm of Spider-Vampires lived inside, keeping it safe and silent.

Isn't that cool? An epic-level Disrupt Undead spell with the Somatic component as music, using a massive massive organ.

Puzzles inside included operating the massive organ stops to produce different chords, stuff like that.

Also, if I was a bard lich, I would provided my favourite instrument and expect anyone trying to enter my sanctum to play my favourite song. There wouldn't need to be any clues, I'm not going to forget that.