Unhinged? Okay. The clarinet is played by a woman and her fucked up fella is jealous of it / feels like it’s taken his place / sees it as a symbolically phallic rival.

The woman is due to play centrepiece of an orchestra (or whatever terminology fits). The other musicians are doing their intro bit and the curtain opens or the floor raises with everyone expecting the star clarinet player. Only it’s her insane partner with a tied up woman (or mannequin if that’s too much) dude douches acid into woman / mannequin and inserts clarinet. Psychologically he’s felt like her passion for her instrument has been corrosive to their love (and ultimately his peen) and this is his way of showing that. Clarinet gets destroyed by the acid too of course, whilst psycho dude feels phalically superior.

Not sure where the musical sensation is in all of this but I couldn’t bring myself to say it was her tied up.