I think you are looking at it incorrectly.
Typically trpt 3 is not higher than trpt 2 and difficulty is not assigned by chair.
Melody is often times easier to play than harmony and the further you get from the melody or common harmony the more difficult it can be. As far as technical ability all players should be able to play anything the person next to them can.
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Go on line, or go to the library, and study some scores. Scores for study are not very expensive.
Thanks for you reply. Sorry, I got confused about some stuff I read about french horns. But going back to your comment that all the trumpeters should be equal in ability, surely that can't be right? I mean, don't the hardest parts usually go the principle (tpt I)? So surely it follows that tpt II would get the less difficult music and tpt III and IV the least taxing?
Often the trumpets will all be playing the same rythms. The 1st trumpet getting the melody and higher notes. The 2nd will get a good basic harmony and the 3rd will get the lower notes in the difficult range of the instrument to project.
That being said; yes there are some composers who compose for hgih school or middle school bands that do make 2nd and 3rd parts more simpler believing the talented musicians will be on these parts.
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Of course you are the composer, you can write whatever you want. If you are doing orchestra, get a hold of the score for Mahlers, 6th symphony. I think he uses 7 trumpets in that piece. That would be a good study for you and give you some good ideas. Mahler is a good music painter and he does a lot of stuff with his 6th symphony.
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