Show off your theory chops with my weekly challenge! You’ll find a new question here every Monday. Please comment to post your reply.
This week’s challenge:
If an orchestral piece is in the key of A major, what key signature would the B-flat clarinet have? If it’s an A clarinet?

Reply to post your answer, and check back on Friday, August 6th to see if you’re right!
ANSWER for 8/2/21

Clarinets, like all transposing instruments, come in different sizes, and this affects their sounding pitch. If a Bb Clarinet plays a C on the page, a Bb is heard. The instrument transposes down a major second, so its part must be written a major second higher to be at concert pitch. So, if the piece is in A major, the Bb clarinet part will be written in the key of B major, with five sharps. The purpose of transposition is so that the player can learn the music on one size of clarinet, then play it on another without having to change fingering.
Wind and brass players generally dislike reading in keys with many sharps, and the five sharps of B major are certainly a lot. In the key of A major, it’s therefore more convenient to play on an A clarinet, whose part must be written a minor third higher than concert pitch. This lets the player read in C major; no sharps there!
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I’m a clarinetist so I know these intimately–will avoid commenting to help the others. LOL! 😉
I knew this one would be way too easy for you!
1) B, 5 sharps. 2) C
A) up one full tone, so the Bb instrument would play in B.
B) up one and a half tones, so the A instrument would play in C.