Question about Transposing: Score vs. Midi Output

[Robert Schmaus]

Hello fellow Lilyponderers,

I'm currently typesetting a score for Bigband, i.e. lots of transposing 
instruments. I'm writing everything in concert pitch, so I can check 
everything with the midi output. My initial idea was that I would 
transpose the individual instruments into their desired key, once I have 
finished the concert pitch score.

Recently, I discovered the \transposition command, and had hoped that 
this would actually be an elegant solution: still writing everything in 
concert pitch, but the engraver would set each voice in its correct key. 
So, in the example below, the Tenor would play the same note as the bass 
(modulo octave) but the notes for the Tenor would show d. The Midi file, 
however now has the tenor play b-flat.
So, I still would have to write every instrument in its own key, but 
would have a correct midi output.

My question is: is there an "inverse" command to \transposition, where I 
can write everything in concert pitch, s.t. the midi output will also 
remain in concert pitch, but the score is actually correct?
An alternative would be to use the right \transpose command for each 
instrument but suppress all \transpose directives for the midi output - 
is that possible?

Thanks a lot.
Have a nice sunday,
Robert


\version "2.14.1"

Tenor = \relative c'' {
        \clef treble
        \transposition bes
        c c c c
}

Bass = \relative c {
        \clef bass
        c c c c
}

\score {
        <<
                \new Staff \Tenor
                \new Staff \Bass
        >>
        \layout{}
        \midi{}
}