If you’ve been reading my blog long enough you already know that I’m interested in the science of music and pedagogy. I feel that since so much of our art form is very subjective, whenever we can take an empirical look at bass playing and teaching it can offer objective insights into how we practice and teach. So I was very interested when I discovered an article, reprinted from the Utah Music Educators Journal, titled “Practical Brass Physics to Improve Your Teaching and Playing.” Unfortunately, I’m not very certain that the physics are practical, or even necessarily true.
The article is written by either Steve Oare or Shannon Roberts, it’s not clear. The byline states Oare, but then there is a photograph of Roberts prominently displayed at the top of the article and other photographs in the article show Roberts. Regardless, the author wrote that after witnessing a master class by Allen Vizutti that his teaching and playing were transformed by what he heard. He decided to investigate the ideas further to see what physics had to say about the concepts Vizutti discussed regarding “smooth air” and “no buzz techniques.”
But even with these successes, I still harbored the following burning questions. How does this technique actually work? What are the physical mechanisms that make this work for brass players at any level? How can I teach this to students and colleagues and support it with evidence? These questions subsequently led me to investigate tube physics, air jets, oscillators and any topics that could provide answers and evidence for the smooth air and no buzz techniques. What follows is a summation of this scientific information and some practical applications to teaching and performing.
The first issue to discuss here is the author’s research methodology. He had some questions and tried to find answers that supported his preconceived notions. Right from the beginning, his research is biased. While one could argue that his “research” was informal, when you look for evidence that supports your hypothesis you’re going to miss evidence that contradicts it. This is why the null hypothesis exists. If the author wanted to learn more about the hypothesis that “smooth air and no buzz techniques” works because of physics, he should have looked for evidence that falsifies the research question. If none exists, then he’s on to something. Any evidence that he presents now is tainted by researcher bias.
But that doesn’t mean, in and of itself, that the evidence isn’t correct, just that we need to really take a much closer and skeptical look at it. He lists three basic topics of misconception in brass playing, embouchure mechanics, mouthpiece function, and tube mechanics.
1) Embouchure Mechanics:
- Buzzing is the technique that produces the best sound on a brass instrument. False
- Buzzing the lips to match pitches translates into pitch accuracy in the instrument. False
- Buzzing is the only way that one can make musical tones on a brass instrument. False
All three of these “misconceptions” rely on the belief that the lips don’t actually buzz inside the mouthpiece when playing. This is explicitly stated later in the article.
- The formation of the lips creates a natural opening (aperture), similar to vocal folds that act as frequency oscillators.
- As air is forced through the lips, the lips never touch each other. Instead, they oscillate because of the shifts in air pressure, turbulent eddies in the mouthpiece and elasticity of the skin.
The first bullet point is more nuanced than the author acknowledged and the second is wrong. The lips do in fact touch each other, otherwise there would be no sound. At this point anyone who states the lips don’t actually open and close while playing isn’t paying attention, there is just too much evidence (both theoretical and observational).
There are many more you can find, but the idea that the lips do not buzz while playing is false, therefore the “no buzz technique” the author is advocating for is highly questionable. We can discuss whether the playing sensation of not buzzing the lips to play is helpful or not, but the reality is that no buzz=no sound. Buzzing is the only technique that will produce a sound on brass, not just the best sound. Whether or not the lips actually vibrate at the frequency of the pitch is irrelevant to his hypothesis, but again, it’s much more nuanced than the author presents.
In general, I think it’s fair to state that the lips do vibrate at the frequency of the pitch being played, with a caveat. The research I’m familiar with on this topic often show that the lips vibrate at a frequency that’s typically just a touch above of the pitch frequency.
The players normally played at frequencies about 1.1% above that of the impedance peak of the bore, but could play below as well as above this frequency and bend from above to below without discontinuity.
Trombonists normally play at a frequency slightly above a bore resonance. However, they can “lip up and down” to frequencies further above the resonance (more compliant load) and below (inertive load).
– Trombone lip mechanics with inertive and compliant loads (“lipping up and down”)
All measurements revealed a strong mechanical resonance with “outward striking” behavior; the played note always sounded above this frequency. Several measurements also showed a weaker second resonance, above the played frequency, with “inward striking” behavior. The Q values of the dominant resonances in human lips were lower than those typical of artificial lips.
– Mechanical response measurements of real and artificial brass players lips
The results show that with extreme efforts the players can generated playing frequencies both lower and higher than the corresponding air column resonance, but that the playing frequency under normal playing conditions (the “most comfortable note”) is almost always higher than the corresponding air column resonance. This supports the view that human lips function as “striking outward” reeds.
From a practical standpoint, I feel it’s fair to say the lips do vibrate at the frequency being played, or near enough. Certainly it’s not something that we can feel or hear while we’re playing, it’s something that can only be checked with special equipment. What this information doesn’t support is a “no buzz technique.”
Some of the author’s argument conflates feeling with reality.
For example, one’s lips feel like they are buzzing when they play. It is intuitive, then, to conclude that the buzzing is the cause of the tones being produced. But it will be shown that the lip buzz sensation is not a cause but an effect of several factors: air jets, pressure changes in the mouth cavity, strong turbulent eddies in the mouthpiece, a frequency feedback loop to and from the lips, and mouthpiece cavity resonance.
In order for a tone to be produced on a brass instrument the lips must oscillate (opening and closing) before the standing wave reflects back and helps to support the lip vibration. Again, one can discuss the benefits of feeling like the standing wave sets the lips to vibrating, but without the lips oscillating to start with, no tone can be produced. Certainly if we want to attack a pitch cleanly the lips (and air, tongue, fingerings/slide position, etc.) need to be set correctly for that pitch. If the author’s hypothesis were correct, how does the instrument know the musician wants to play a low C or a high C?
Another example is the technique of placing and sealing lips into the mouthpiece. It naturally seems that the cup “captures” a pitch created by buzzing lips. It will be illustrated that this is false. Instead, smooth (laminar) air flows between the lips & into the mouthpiece, which produces Aeolian tones and maximal resonance of the mouthpiece cavity. These actions excite the harmonics of the standing airwave in the instrument to sympathetically resonate. In effect, the air column resonates in a similar fashion to a string on a piano.
Getting into the weeds of the acoustics is not in my wheel house, so I’m a little unsure about the above. Best as I can tell, the flow of air into the mouthpiece is not a “smooth (laminar)” flow, the air is pulsed into the mouthpiece cup as the lips open and close. After the air passes the lips it swirls inside the cup before it gets blown into the shank. An Aeolian tone is created when air passes a solid object and generates an oscillation of the air stream, such as a flute tone or whistling. Brass playing are sustained lip-reed oscillations, not Aeolian vortex tones.
Now it is true that the brass tone is the air column inside the instrument oscillating, which strings do as well. Where the piano string analogy breaks down for brass is that we only rarely play the fundamental of the air column, we are almost always playing on the harmonics of the vibrating column of air inside the instrument. On a piano the string length determines the pitch. On brass, the frequency of the lip vibrating influences the column of air to develop nodes and oscillate on the harmonic series.
When the author “puts it together” he included a graphic representation. Take a look at it.
Now take a look at the graphic I created way back in 2010 when I needed an image to spice up a blog post.
It’s a pretty poor job of graphics, to be honest. I just wanted an image that depicted a brass musician playing with the tongue tip touching the bottom of the lip (as something to avoid, by the way). I don’t know why the author took this crappy image for his graphical representation, since it really doesn’t add anything. I might have even granted permission to use it, if I had been asked.
In short, buzzing has no positive effect on tone production. It is merely a sensation felt on the lips due to air pressure changes. An effective experiment one can try is to simply blow air into a mouthpiece while inserting it in a brass instrument. The result is the Aeolian tone Mouthpiece Effect. No buzzing is ever needed. One can also try the opposite. Buzz into a mouthpiece while inserting it. Do not alter the buzzing in any way. The resultant sound is kazoo-like and uncontrolled. A comparison of the muscular positions and tensions of the buzz and smooth-air techniques yields some interesting results. The photo and spectrographs, which follow, illustrate those results.
Yeah, not really. If one were to conduct the above experiments utilizing artificial lips I suspect that the results might be different. Trying to do this with a human being will result on the musician making micro-adjustments, perhaps even without realizing it. Blowing air into the mouthpiece while inserting it into the instrument does, in fact, alter the conditions and the resulting back pressure can indeed make it feel as if the lips begin oscillating on their own, but that’s just the player making enough adjustment to get the tone started. Try doing this with a high C, instead of the low pitch that you end up with this experiment.
Likewise buzzing the mouthpiece and then slotting it into the instrument requires some adjustments. The lip position and blowing activity is different between mouthpiece buzzing and playing the instrument. The author pointed out that the mouthpiece itself has a natural (very high pitch) resonance. Buzzing on the mouthpiece alone requires the player to lip the oscillation to the desired pitch and this is quite easy to do on the mouthpiece. Adding the instrument then adds the resonance of the air column inside of the instrument and influences (not creates) the frequency of the lip vibration. So by mouthpiece buzzing and slotting the instrument you’re going to need to make an adjustment or else you will get an uncontrolled and kazoo-like sound.
The author does eventually get down to brass tacks (no pun intended) with some practical suggestions.
- Always incorporate breathing exercises into every practice session. This promotes more lung capacity and the ability to produce steady laminar air.
Straw Blowing to achieve laminar (smooth) air. This is one of the most beneficial exercises a brass player can perform. Place the straw between the lips. The straw should make no contact with the teeth. Simply practice blowing long phrases/tones into the palm of the hand. Concentrate on steady smooth air. Follow this immediately by blowing into the instrument. The results are remarkable. One can see and hear immediate improvement. This is very beneficial for students who are currently having difficulty with tone production.
- Make an “M” for embouchure formation. The “M” position of the mouth, as in the word “mom”, is the most natural brass embouchure. It places the lips in a very relaxed and supple position for smooth air production.
- More closed M for higher notes, open for low notes. This is a productive method for register change. Tighten the “M” as if one is squeezing a straw between the lips. This can be practiced with the straw ahead of time. Emphasize steady air when shifting to the next overtone.
Breathing exercises are fine, and probably to be encouraged. The idea that one can increase lung capacity is a myth on its own, but not worth going into right now. Laminar air flow doesn’t really apply to brass playing, which has the pulsating and varying jets of air.
Straw blowing might make for a way to lead a player towards a particular playing sensation, but doesn’t recreate the way the lips actually vibrate. It might also lead to the student going too far in that direction. Use that exercise with caution.
Setting the embouchure formation with an “M” syllable is fine, I use that analogy all the time. However, I prefer not to describe ascending as “squeezing a straw between the lips.” My concern here is that the squeezing action results in bringing the mouth corners in from their position as ascending, rather than keeping them lock in the same place for the entire range. Sure, if a student has difficulties with pulling them back with a “smile embouchure” the sensation of bringing them in like you’re squeezing a straw between your lips might help. But some brass musicians have the opposite problem, their mouth corners get pulled in towards the mouthpiece rim, which can choke off the sound and make it difficult to ascend from the upper register without resetting the mouthpiece (I speak from personal experience here).
Conclusion
If something in the article speaks to you and helps you with your playing and teacher, that’s just fine. Don’t mistake the playing analogies and playing sensations the author is claiming to be actual fact. I find his claims that the lip vibration is merely a playing sensation ironic. The physics he covers have just enough truth to them to sound legit, but not enough to be objectively helpful. Is the article inspirational? Maybe, but I was just disappointed.
