Schuller on the Embouchure

from Gunther Schuller: Horn Technique

​The position of the lips, or what is commonly called the embouchure, plays an important role in the production of a fine tone. Technically the embouchure refers to the position and tension with which the lips and surrounding face muscles are held, in order that air blown through the lips may cause them to vibrate at certain speeds and thus produce certain pitches. There are four ways in which pitches can be altered by the embouchure: one is by pressure upon the lips from without (the mouthpiece and horn); the second is by changing the size and shape of the lip opening; the third is by altering the degree of tension in the lip muscles; and the fourth is the angle at which the air is directed into the mouthpiece. The first approach is controlled primarily through slight pressures applied by the left hand, while the latter three are governed by the movement of the jaw, the lower teeth, and the lip muscles themselves.

Before we investigate these points further, we had better find out exactly how the mouthpiece should be placed on or against the lips. The most natural method for finding an embouchure that I know of is the following: relax the lips into an absolutely normal closed (not tightly closed) position. Take the mouthpiece and place the upper half of the rim on the upper lip, so that the rim catches the two slight curvatures found in most lips. This will put the uppermost curve of the rim into the 'white' flesh, and will guarantee that the mouthpiece is more or less well centered. Without changing or lowering the lip position (i.e. relative to the upper lip), tense both lips into a slightly pursed position. In most cases this will put the lower curve of the rim just within the 'red' of the lower lip. Blowing air with sufficient speed against and through the properly tensed lips into the horn will produce a pitch.

This procedure ensures the proper representation in the embouchure of both lips, and at the same time places the upper and lower rims of the mouthpiece on the lips in such a way that pressure is exerted on the teeth just inside the gumline-- assuming incidentally that the teeth are held apart at the proper distance of about a quarter of an inch. Some players prefer an embouchure in which the rim of the mouthpiece sits outside the red of both lips. In this case the centers of both lips are entirely inside the mouthpiece. Although some players are able to use this embouchure effectively, I have had no experience with it personally. But from my experiences with students, I would say that such an embouchure is problematic and unsuccessful in a majority of cases.

With the mouthpiece position I have suggested it is generally possible to negotiate with ease the entire four octave range of the horn. This is accomplished, as I have indicated earlier, through the simultaneous interrelated application of four procedures: for ascending pitches, slight pressure is applied on the upper lip, the lip opening is made smaller by a proportionate inward and upward movement of the jaw and lower teeth, the lip muscles are proportionately tightened, and the air stream is directed increasingly downward and closer to the mouthpiece rim. For descending pitches, slight pressure is applied on the lower lip, the lip opening is made larger by a proportionate downward and outward movement of the jaw and lower teeth, the lip muscles are proportionately relaxed, and the air stream is directed more horizontally at a point in the mouthpiece cup closer to the bore. It can not be emphasized sufficiently that all these movements, especially those which involve pressure on the lips, must be moderate and in proportion to the interval change desired.

The halfway point between the two poles in embouchure positions occurs where the teeth are more or less vertically in line (i.e. flush), and where all the other movements and pressures are at an equally mean position.  The horizontal as well as inner muscle tension of the lips is controlled by the muscles in and around the corners of the mouth. It is a salient feature of the embouchure I have thus far described (or for that matter any embouchure) that the corners of the mouth must stay, no matter how relaxed or how tense, in the same position (i.e. the corners of the lips should not under any circumstances pull up or down.) Special care must be taken not to 'spread' the corners (as in a smile) when going into the high register. The original corner position, which is halfway between that of a smile and a pucker, must be maintained throughout the entire range of the horn. If an analogy can be made, the lips and the mouth corners can be likened to a hammock swinging between two trees. The trees never move, while the hammock is free to pivot back and forth. If the corners pull away from the mouth centre, the lips will become too tight and thus will not vibrate properly. Imagine the trees suddenly leaning away from each other at a 45 degree angle. Equally negative results occur when the corners relax too much and come forward. The resultant lack of tension leaves the lips in a collapsed state; or as if our trees were to lean toward each other, making the hammock sag. The best way I have found of teaching this correct corner muscle tension is to think of these muscles as coiled upon an imaginary axis and anchored tightly against the teeth.

I have mentioned that the direction in which the air stream is projected into the mouthpiece is also of great importance. This aspect of tone production is seldom discussed or taught, and yet it is inseparable from the other three factors in producing a controlled tone on the horn. This idea is largely ignored because, in terms of palpable physical movements, it is the subtlest of the four pitch-altering procedures. In fact, differences in the direction of the air stream can be felt only between larger intervals or extreme register changes.

This concept of 'air direction' is based on an acoustical principle of wave reflection', whereby the air stream is reflected or bounced off the walls of the mouthpiece before it enters the mouthpipe of the horn itself. For a high pitch, the air stream must be reflected at a point relatively close to the rim and lip aperture. For a lower pitch, a correspondingly lower reflection point is necessary. The necessity for the air stream to be directed in this way will be understood and felt most readily if the player will produce the natural notes (overtone series) in an unbroken slur. The actual shift of direction becomes quite noticeable, especially between the larger intervals in the lower part of the series. On the modern double horn, the availability of pitch lowering valve action makes us less conscious of this directionality factor. Nevertheless, it is a fundamental aspect of the interrelated four-way process of tone and pitch production.

The direction of the air stream is controlled by the jaw and teeth positions. Obviously, a slightly forward position of the lower teeth will direct the air more horizontally, while a receding jaw position will point the air stream correspondingly lower. Such jaw movements also alter the angle of the mouthpiece in relation to the air stream. It is in this connection that I have found a slight 'riding up' on the upper lip for the extreme high register very helpful. It too helps to direct the air stream in a more vertical line, at a reflection point in the cup which is closer to the rim than to the bore.

The player should also guard against letting his cheeks puff or allowing air pockets to form behind either the upper or lower lips.  I am also an advocate of the moist embouchure. Although at a beginner's stage this makes the high register harder to attain, eventually, as the muscles strengthen and a niche for the rim is found on the lower lip, this feeling of insecurity disappears. It will then be found that a moist embouchure gives the player greatly increased flexibility, especially in slurring.