If u are talking about tenors only and not comparing it with the sop, then i too do not believe that the curvature of the horn affects the horn. The curvature only changes the direction in which the sound comes out. Be it the to the top or side. Not touching on the octave key, from C down, u may have already realised the more holes u cover the lower ur sound. So, in order to cover the full length of the enclosed tenor body, u have to put in more air. Like when u play a low C on an alto, a tenor, a bari. Therefore, the longer body, the longer the distance the air must flow, the more air u need. Correct? Wat do u mean by 'if I put too much it will jump to the next harmonic series.' ? Do u mean the sound will go higher? Sorry, because we dun usually use 'harmonic series'. If u mean that the sound goes higher, it is because of the direction ur air hits ur reed and how much u open ur throat. Whether is it hot air or cold air. (i may have errors, so correct me if found) -Kerqt