John Q. Ericson
Outside of the horn world there are a few concepts and terminologies we could stand to adopt. David Hickman in his recent publication Trumpet Pedagogy defines two types of embouchures. One is the fixed-jaw embouchure, a type that won’t work well on the horn at least in the lower register. The other type, of more interest to us, is the floating-jaw embouchure.
The mental image of the jaw floating as we play in and out of the low range is an excellent one. The whole topic of jaw position and horn playing is a big one and actually one with some variety of approach. Farkas in his publications described in general a type of very square jaw position and other authors have described a more receded or downstream position without directly addressing the question of why their approach differed from Farkas. The truth is most players play in general somewhere between those extremes in the upper register but into the low range the jaw position must change and it is more complicated than just dropping the jaw (although I do like the simplicity of that image).
This fall I had an interesting experience as one of my TMJs (we all have two of them—the TMJ is actually the joint at each end of your jaw, it is not a condition) was bothering me. It is feeling better now (whew! TMJ issues are a separate topic) but when it was bothering me I could feel clearly just how much the jaw floats, something I was not nearly as aware of.
It is not something you want to over analyze but let us take for example low C. I found that my jaw was in a different position for loud and for soft playing and also in a different position if I was tonguing the note or if I was slurring. The motions of the jaw as it floats into the place required for any given dynamic or articulation are subtle but actually pretty amazing.
The main thing to focus on as a player is to let the jaw be where it needs to be to get the result. If you are not getting the result it may pay off to try floating to positions that include more of a drop and a slight forward motion. For sure I do both, and the combination is what gets my tongue and lips into the positions they need to be in.
Consider the idea of the floating jaw. It would be a good terminology to adopt into the vocabulary of the modern horn teacher