Posted by Jay Bertolet on March 24, 1999 at 11:52:54:
In Reply to: Intonation question posted by Tom on March 24, 1999 at 09:59:14:
I think you're on the right track but I can make a suggestion you may not have considered. You mention pulling the valve slides to correct intonation. Obviously, this is a very common technique. But the down side is that you have to switch valve slides every time you change whichever valve combination you are using. Not to disrespect the post by "Alan" but I completely disagree with the notion of "fighting" the tendencies of an instrument. The implication is that if you're not pulling slides, you're "lipping" pitches into correct intonation. I would strongly discourage you from doing this! Anytime you change the embouchure, you change the quality of the sound. By lipping pitches up or down for intonation purposes, you risk producing a non-centered sound that neither projects nor is consistent with other sounds you make.
In my playing, I have operated under the premise that the only suitable way to adjust intonation is by pulling slides or by using alternate fingerings. That way, hopefully, my sound is characteristic and consistent. I use on all my instruments a main tuning slide stick that allows me to adjust the main tuning slide either in or out. That way, I can leave all the valve slides in a "neutral" position, seal all the vents on my rotary valves, and only have to adjust one slide for all notes. Also, this allows me the possibility of adjusting open notes which I couldn't do using only valve slides. And I never have to adjust pitches with my lip which makes it easier for me to maintain sound quality and consistency. It does take some time to learn the use of the stick but in the long run, it is the easiest and most flexible system I know of. I've also noticed that my accuracy has improved since I've made a conscious effort to keep my embouchure consistent.
Good luck!