Any musical instrument you just don’t like hearing? My vote is the vibes. Every time I’ve heard it, it’s just this annoying plinky sound. Play it fast, it’s plinky. Play it slow, it’s plinky. Plus isn’t it kind of pointless to have an electrical instrument that can’t distort or be played loudly?
I can live without bagpipes.
Bagpipes and most instances of saxophone. Harmonicas aren’t very pleasant, but they get a pass since my dad plays.
Guitar
Removes gloves
flute. Hate it.
Like the recorder, though. Go figure.
My husband’s hurdy-gurdy. He put it together from a kit.
I hate rock saxophone. Jazz, fine. But it ruins almost all rock, Springsteen included.
Joe
Brass. Played solo, I like them fine, but when it’s a whole section, I want to wrap my head in soft thick batting.
Saxophone unless:
For Jazz, Paul Desmond can play all day long. And for R&B/Rock, King Curtis is God. The rest of them can screw off.
One more exception - the guy that played on “Baker Street”
No, you just haven’t heard enough of them at the same time.
Your husband is an authentic Evil Genius. A regular, run of the mill evil person would just buy a hurdy-gurdy in a store or on-line. It takes a special sort to build one from a kit.
Does he have a newsletter, and can I subscribe?
For me, the sitar would be pretty high on the list.
Don’t think I’ve heard anything on a Theremin that appeals much, and that includes the Good Vibrations intro.
Steel drums aka steelpan
Fuzztone or solid-state distortion on a guitar. Either one will make me want to take an exploding chainsaw to my eardrums.
I would vote Theremin, but I’m not even sure if it’s a real musical instrument. More like sound effects. Really annoying sound effects.
No, it is a real instrument, played by real musicians, and written for by real composers.
You may not like it, but it is definitely real.
Ha! (He may have to come up with one, just for that. 
)
Aren’t those rosewood marimbas, rather than aluminum vibraphones?
Personally, almost every post here makes me think of music I love with that instrument.
Here is a track I like with a theremin (not shown; the radio is a joke). This may be for some a more familiar and more overt demonstration of what a theremin can do.
Drumming… just a high bass beat. No melody or rythym to accompany. Drumming is useless, and drummers are hacks. Don’t get this modern bass beat econo9my of rap. That’s a drium and somebody speaking… not melodious… not music.
Definitely bagpipes. Not a musical instrument, but an instrument of torture.