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VERTICAL MOUTHPIECE POSITION AND RANGE

Deciding on a vertical mouthpiece position is fundamental to playing the trumpet and a decision that is made, sooner or later, by all trumpet players. The trumpet can be successfully played using a variety of mouthpiece positions. These can range from positions having very little of the mouthpiece on the upper lip to those having very little of it on the bottom lip. Half on each lip is a frequently seen position. Arban (ref. 1), suggests that we place one third of the mouthpiece on the top lip with two thirds of it on the bottom lip, the so called "1/3, 2/3" position. Some players prefer more of a French horn position having as much as two thirds of the mouthpiece on the top lip. The position a player ultimately selects seems, in many cases, to be strongly dependent on his initial training and comfort level. Students frequently get their first exposure to the trumpet from primary or secondary school band directors who may not be trumpet players and who may suggest a "half and half" position (half of the mouthpiece on each lip) based on what seems logical to them. And, many players are reluctant to change this initial position after having acquired some success with it. This is all the more reason to give careful consideration to this aspect of playing, should there be any reason to think that all positions do not perform identically! Some expertise has been attained with all of these positions; but we might still ask, "Why play one way, and why not some other?" This brief note will attempt to address this question by comparing two typical positions and providing a rationale for selecting one over the other, while keeping in mind that successful performers can always be found who use various positions, and that the selection of any position must, of course, be left to the player. In order to do this, a brief review of embouchure mechanics is necessary.

The sequence of events that takes place when we blow into the trumpet and attempt to sound, let's say, a middle C, is as follows. First, as air pressure builds in the mouth behind the tensed lips, one lip, the top one, will deform (move) more than the other, the lips being of unequal strength, possibly elasticity, and tension, due to differing musculature and contractive effort (ref. 2). This movement is ultimately sufficient to cause the lips to separate at the aperture, at which time a tiny puff of air rushes into the mouthpiece. Immediately following this, the air pressure in the mouth, behind the lips, being thereby relieved, falls slightly, allowing the top lip to return to its contractual state just prior to the lips opening, and thereby closing the aperture. This can be thought of as the upper lip "snapping back" into its original position. The air inside of the mouthpiece now contains a pressure pulse followed by a relative rarefaction, the aperture now being closed. This pulse propagates as a wave at the speed of sound (about 1100 feet per second) through the mouthpiece throat and into the horn. The process then continuously repeats, and we find that the requisite compressions and rarefactions necessary for sound are present in the air in the horn bore. (The mechanics of the development of reflected pulses into standing waves is of no interest here and will not be discussed.) Simultaneously, a relatively slow stream of air is passing through the mouthpiece and into the horn as these pulses are being generated. When the pulses occur as frequently as 440 times a second, the sound produced is A; when they occur with a frequency of 512 times a second, the sound is C and so on. We refer to this continuous, repeated "pulse generating" activity as "vibration" of the lip.

We note that throughout most of the trumpet range (say middle C and above for example), essentially only the top lip is "vibrating" (ref. 2). For the lower notes, the bottom lip may or may not possibly also enter into the process. At what point the bottom lip may contribute significantly to the vibration (opening and closing) depends somewhat on the player (his muscular contraction, mouthpiece position, physical condition of his lips, etc.). This is hard to detect by feel because the top lip is always vibrating against the bottom lip; this gives the sensation of vibration in this lip. Sound intensity is also obviously important. For fortissimo low-register playing, for example, significant movement of the bottom lip is likely, the lips being in a comparatively flaccid state and air flow relatively high. The point is, that for the relatively higher range (say middle C and above), the top lip is "vibrating" more or less exclusively; the bottom lip remains essentially stationary. Henderson (ref. 2) described the procedures and equipment he used to demonstrate this, most of which are easily duplicated. He also showed the manner by which the embouchure is manipulated to raise pitch.

Contrary to what is commonly thought, lip tissue tension is a much less important factor than upper lip mass, when raising pitch (ref. 3). Henderson found that the principal method for raising pitch is to reduce the effective vibrating mass of the upper lip. This is accomplished by an upward push of the bottom lip. As the upward pressure exerted by the bottom lip on the top lip increases, the amount of top lip tissue available to vibrate (its effective vibrating mass) becomes progressively smaller, the top lip becoming more and more "immobilized" as those parts of it, especially nearest the mouthpiece rim, become relatively stationary. Stated a little differently, as the bottom lip pushes progressively upward, the effective size (vibrating portion) of the upper lip becomes progressively smaller and restricted to tissue that is nearer the aperture as the outermost tissue nearest the rim becomes increasingly immobilized. The smaller the effective vibrating mass of the upper lip becomes, the higher the pitch that is generated. There is also a resultant increase in lip tissue tension due to the increased bottom lip upward push, which contributes, but to a lesser degree, to pitch increase (ref. 2).

With the above in mind, we now consider two mouthpiece positions as shown in the following diagrams:

The circles represent the inside edge of the mouthpiece rim. The horizontal lines through these circles represent the juncture of the lips for a "half and half" mouthpiece position (diagram A) and for a "one third upper, and two thirds lower" mouthpiece position (diagram B).

If we reasonably assume that, due to musculature limitations, a player is capable of only so much (and no more) upward push with his lower lip in either case (A or B), it is apparent that choosing the mouthpiece position depicted in diagram B gives him a "head start" when he attempts to elevate pitch, i.e. because there is less upper lip mass (to immobilize) to start with (when using the "1/3, 2/3" position), his bottom lip "upward push" capability will be acting on a smaller initial vibrating mass and will not be partially dissipated (used up) by top lip tissue that has been removed from the system by virtue of this selection (he would have to immobilize this extra tissue first, to get to the same point if he had selected the "half and half" position). Thus, for the same amount of upward "push", the force per unit of effective vibrating upper lip mass, will be greater with the "1/3, 2/3" position, and his ability to disable upper lip tissue will be enhanced thus easing his high register and extending his range potential. We might say that he is using the same weapon (or possibly a larger one) on a smaller adversary!!

Approximate calculations show that about 40% of the upper lip mass is removed (and thereby immobilized a priori) by changing from the "half and half" position (diagram A) to the "one third upper and two thirds lower" position (diagram B). This is not to say that any specific note will become exactly 40% easier just by changing positions. It is more to say that the whole problem of raising pitch may be eased somewhat. This problem is complicated by the additional question of the tension effect (albeit a second order one) as well as peculiarities of individual players (lip condition, dental formation, etc.). Modeling the lip mass by assuming uniform upper lip thickness (as was done here) as well as other possible intrinsic simplifications, that I am sure some astute readers will note, may also contribute, somewhat, to the uncertainty of this analysis. At best, however, we can probably say that the first order discussion presented here appears instead to suggest that (a.) more than a little thought should be given to mouthpiece positions, and (b.) there is a good chance that we may be able to improve our high register by moving the mouthpiece down a bit; it's certainly worth a try.

References

1. Arban, J. J. B. L., Complete Conservatory Method for Trumpet (Cornet), p. 7, Carl Fischer Inc., 1982.
2. Henderson, H. W., An Experimental Study of Trumpet Embouchure, Journal of the Acoustical Society of America, Vol. 13, pp. 58-64, July 1942.
3. Lynch, J. H., The Asymmetric Trumpet Mouthpiece, International Trumpet Guild Journal, Vol. 20, No. 3, pp. 52-55, February 1996.