There are precisely two instruments on this world I would try to learn:
the bag pipes
Because, to my knowledge, it it the most annoying instrument known to humanity. It's loud, it's screechy, it's haunting, it's everything hateful in a music instrument and yet it is so damn epic sounding.
the hurdy gurdy
Silly sounding name for an instrument capable of sending shivers down your spine.
It is also ridiculously cumbersome and unless you know what it is, the basic reaction to it is wondering if a piano, an accordion and a jack-in-the-box had a threesome and nature decided to create the musical instrument equivalent of the platypus.
I like this instrument so much I created a character for a story that is a necromancer bard, that conveys spells through the music of the hurdy gurdy.
This makes me want to learn the hurdy-gurdy even more! I mean, in reality, I'm never putting in the time to learn to play it anyway. So, in the fantasy of me being dedicated enough to learn to play an instrument, the added fantasy of me maintaining a finely tuned instrument is just added appeal.