I am curious why professionals wouldn't prefer transposed parts for F
horns.
The way you read, or rather think of, a part that is, for example, in D is different from the way you think of a part in F. The D horn had a darker sound, so, reading a horn in D part, one tries to adopt that sound. Likewise for parts in other keys - each key has its own characteristic sound and its own "feel".
When I read a transposed part in F which was obviously written for a horn in Eb, it is very difficult not to transpose it again because the feel is different - my head goes into the original key with everything this implies.
In addition to this, an original part is much easier to pitch - it is, in most cases, clear whether you are aiming for the tonic, the third or the fifth for example.
I and most (all?) of the horn players I know, would much rather read an original part than a transposed copy. Transposed copies are good only for kids who haven't learned their craft yet. :-)
All the best,
Lawrence
