The Role of the Lower Jaw when Descending on a Brass Instrument

For decades brass teachers have been teaching students to drop their jaw when descending. Many method books also recommend the same. Gradually, however, more brass instructors and authors have been moving away from this approach and instead recommend keeping the amount of space between the teeth more consistent when playing, for a variety of reasons. Before commenting on why I believe this is more correct, from a mechanical point of view, I'd like to address some of the arguments for dropping the jaw to descend.

1. It makes it easier to descend.

This is indeed true, but I feel it's important to understand why this is the case. Dropping the jaw is a replacement crutch for relaxing the embouchure formation, as what you do is loosen the amount of lip compression not with the embouchure muscles, but by pulling the lower lip down via the jaw drop.

2. It's necessary for the oral cavity to be larger to open up the sound in the low register.

While I'm not an acoustician, it's been explained to me by colleagues who do have a background in acoustics that this is a fallacy. The oral cavity isn't a resonating chamber, all the sound happens at the lips and beyond. What is necessary, however, is that the air pressure needs to be reduced and at the same time the amount of air needs to be increased. This should ideally happen not only in the breathing process but also through a lowering of the level of tongue arch inside the mouth. Dropping the jaw automatically lowers the level of tongue arch without needing to move the tongue at all, just the jaw. In other words, jaw dropping compensates for a lack of lowering the level of the tongue arch.

3. (Insert famous player's name here) drops his/her jaw to descend.

Your mother probably has already pointed out the flaw in this sort of argument. If famous player X jumped off a building does that mean you need to as well? Consider that not only has the traditional approach to playing a brass instrument changed over time as we gain better understanding of the mechanics of playing a brass instrument (for example, smiling to ascend used to be encouraged, but it is largely recognized as detrimental today), but famous exceptions to brass playing "rules" always have and always will exist. Watch videos of Dizzy Gillespie's cheek puffing or Miles Davis playing with his bell pointed straight to the floor for some easy to see examples. Always take what you see and read with a grain of salt (including me and this essay) and instead use logic and common sense to help you determine what is mechanically correct and what is potentially a problem.

Who among us has truly mastered our instrument? Can anyone here honestly state that he or she plays with absolutely no technique flaws? I don't think that even the greatest players alive are "perfect" players. Model your technique based on logical analysis, not blind imitation.

Here are some of my arguments for keeping the position of the lower jaw more stable:

1. It maintains consistent contact with your teeth and lip/mouthpiece rim, regardless of the register you're playing.

This equates as consistent embouchure sensation and helps you avoid twisting or winding up your lips inside the mouthpiece as you ascend from the low register (dropping the jaw to descend will necessitate raising the jaw to ascend back up). Doing so risks not only bringing the lower teeth back into an incorrect position but also the possibility of distorting the position of the lower lip while doing so. Why take this risk if you don't have to?

2. It avoids the risk of pulling the position of the mouthpiece on the lips lower when the jaw is dropped.

This can be particularly destructive to certain types of embouchures, as they often end up with a high register mouthpiece setting and a low register setting. Over time, using multiple embouchures can start to work against each other and cause all sorts of playing difficulties that appear to be related to the upper register, not the lower register. In truth, if these players develop the ability to descend with their high register setting without dropping the jaw they can eliminate or avoid their high register problems.

3. It's unnecessary to drop the jaw to descend.

I haven't worked with a jaw dropping student yet who couldn't significantly reduce or even eliminate dropping the jaw, regardless of whether or not it appears to be causing playing difficulties. At the very least I think all unnecessary movement should be reduced or eliminated. In many cases, perhaps even most, when a jaw drop is significantly reduced or eliminated the player's upper register actually improves.

4. If dropping the jaw to descend is mechanically correct, then raising the jaw to ascend should be correct as well.

Yes, jaw droppers must raise the position of the jaw back to normal when ascending back up, but after the jaw position is back in position it doesn't raise higher to continue to ascend. Watch a player slur from middle B flat to high B flat and you shouldn't see the jaw raise. Watch a player slur from middle B flat to low B flat and the only changes you should see are the same type of changes as the ascending octave slur, but in the opposite direction. These changes should also be the same amount of alteration, not more. Very often you see a much bigger change in the descending octave slur, which indicates the player is descending by collapsing the embouchure formation, not via relaxation and the proper amount of aligning the lips and mouthpiece to receive the air stream (an upward and downward sliding of the lips and mouthpiece together along the teeth).

How can you tell if a jaw drop is causing problems?

First of all, if you know you drop the jaw to descend I believe you're going to be better off reducing or eliminating that movement regardless of whether or not you notice any of the above mentioned difficulties associated with a jaw drop. Very often these troubles don't manifest themselves until years later, making it much more difficult to replace that habit.

However, here's a quick little test to help you determine if you might be in the early stages of allowing a jaw drop to interfere with your playing:

The above exercise is written for trombone or euphonium. Trumpet, tuba, and horn players should either transpose or play a similar pattern that starts in the high register and slurs down to the low register and then back up. What's important for the purposes of checking for problems descending is that the entire exercise be played on one breath and not allow yourself to reset as you slur back up. Play the entire phrase with no tongue, excepting the initial attack. If you have trouble ascending back up after playing the low E, or if you find it's more effort to play the second high B flat, you're doing something in your embouchure formation that is potentially going to cause some difficulties.

Keep in mind that just because you might be able to play the above exercise while dropping the jaw doesn't mean the potential still isn't there for future problems. Try playing it staccato, as sometimes we allow our jaw to move more when the tongue gets more involved. What I'm recommending isn't just for sounding good immediately, but to avoid problems down the road.

How do I reduce or eliminate a jaw drop?

Let's say that you've decided that you want to reduce or eliminate a jaw drop. How do you go about doing this? First, you only should pay any attention to this during your normal technique routine, never while working on music and absolutely never while performing. Practice slurs that start in the upper register or the high end of your middle register (where you're certain you're jaw position is ideal for you) and descend while keeping your jaw position consistent. At first you'll need to decrescendo and play in the low register softer and the tone may be thinner. Daily consistent practice of this sort, however, will teach you how to open up the sound and increase the volume without having to resort to changing the jaw. You just need to relearn how to line up the embouchure formation to receive the air stream, how to position the tongue arch, and how to use the air effectively.

Some players may find the following exercise helpful. Start on a middle register open pitch (middle concert B flat, for example) and attack the pitch as normal. Hold it out for 4 counts and slur down an octave while simultaneously exaggerating your embouchure motion (the natural sliding of the mouthpiece and lips as a single unit along the teeth) while puffing our your cheeks as far as they can go. Strive to play the low octave with as good a sound as possible. This makes it virtually impossible to descend with a jaw drop. Repeat this exercise down in half steps through all 7 positions or fingerings. While this exercise doesn't work for everyone, a couple of weeks of daily practice can often greatly reduce or even eliminate the jaw dropping habit.

Ideally, this should be done with the guidance of a good teacher who teaches technique with a logical, one-thing-at-a-time approach, not because that's how he/she thinks he/she plays or because some method book teaches a one-size-fits-all approach.

In closing, by no means am I suggesting that you should get fixated on your jaw position while playing. Practice daily for "form," but forget all about it when it's time to move on and focus on musicality or other materials.