I was reading a post in the FH forum regarding "if french horn is the hardestbrass instrument" It was an interesting discussion, and it sparked my curiousity...so..
What is the hardest brass/woodwind instrument to play?
Including oboe mussette, tenorassoon (is that how you spell it), etc.

Hmmm...The hardest brass instrument is the French horn by far!!! I play it in my school's band and I think it's easyat times, but other times I stop and think to myself: "Why God?! Why did you let me pick this instrument and not something easy like trumpet?!?" But, the French horn is sooo worth the the hardness when the moments come and you play this bitter-sweet phrasing in songs like the Harry Potter theme, or alot of other songs like that.

The hardest woodwind? That's a tough one for me to answer. But, from what I've heard and what people have told me, I would have to say the basson or the oboe. But, I'm not a woodwind person, I'm a brass and percusion person, so I'm might be wrong on that one.

I think the hardest woodwind instruments to play are the oboe and bassoon. I would say they are the hardest because they are both hard to keep in tune.

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I believe it is the "Tenoroon." I guess any double reed instrument (oboe, bassoon, english horn, oboe musette, tenoroon ect.) could be considered the hardest woodwind instrument because of the double reed.

All instruments have their hard aspects.

But I guess double-reeds are the hardest to be consistent. I can sound completely amazing one day and then the next (on the same reed) absolutely horrid. So learning how to get around the evilness of reeds is hard.

French horn! I love it, when in its tuned right. But when its not, (and most of the times its not) i'm always like " omg, i picked this? why didn't my teacher tell me this was going ot be hard!" but its totaly worth it when its played right ^^

and apparently oboe is hardest of woodwinds. my friend Ducky plays it, and it is like NEVER in tune. lol. its so squeky and difficult, fomr what i've heard.

I picked up a friend's bassoon one day (with her permission of course!) and was immediately able to noodle around in A minor for a little over an octave even though I was clueless about the fingerings. By far it's been the easiest instrument for me to get a good tone out of with the least effort. Of course, I was playing her reed... which of course meant it played. Most of the reason they say bassoon is hard is because the reeds are expensive and difficult to deal with - it's half the art that isn't actually playing the instrument itself. Fingerings are a pain to learn at first, though. Oboe has been the hardest for me - I'd say it's more difficult than the bassoon by far. Since when can you tune a toothpick? Furthermore, I'd put horn above that even. When you learn to blow a reed right, you've already overcome almost half the trouble of learning the instrument in the first place. With horn you are always learning to make you mouth do different thinks. I like to compare it to being an Olympic athlete in the manner in which you have to practice carefully everyday and build up stamina and flexibility little step by little step. My favourite... but GAH is it difficult to sound good on. So easy to crack notes until the time you're about a graduate student in horn performance.