Leaderboard

You would probably have him adjust the mouth piece to go offtune a bit, that might be your best bet.

Small thing: when you were writing out the intervals, I'm pretty sure you meant Bb in the sixth bar (F to Bb - perfect fourth) and B in the following bar (F to B - tritone); F to B# is still an augmented fourth (simply because, by definition, the interval between a note name beginning with F (F, F#, Fb, Fbb, &c.) and a note name beginning with B is always a fourth, if the F is lower); but it's not dissonant sounding, because B# has the same sound as C, which is a perfect fifth.