I suggest the use of flutist Keith Underwood's system of Jurassic breathing to make an aural connection between inhaling with an open throat and mouth and inhaling with the interior of the mouth and the throat too closed.
Balance is everything. Clearly, there are tonal problems associated with too little and with too much lip pressure. The pressure must also be balanced in relationship to the mouthpiece/reed combination and the amount of mouthpiece in the mouth.
I saw Dr. Donald McGinnis demonstrate the ideal lip/reed fulcrum point at an OMEA clinic several years ago by placing a thin business card between the reed and the mouthpiece and moving it down to the point at which it could no longer easily be moved; this is the point at which the mouthpiece curve ends and represents a nearly ideal reference point for lip/reed contact.
Voicing is the one category covered in the clinic that is least frequently discussed in college woodwind classes; therefore, many non-clarinetists are unaware of its importance. I suggest that teachers work with students to help them gain flexibility in voicing by having the student finger low E, place the bell of the clarinet so that it is almost completely closed by a fairly soft fabric, and experimenting with the harmonica-like sounding overtones that are produced. Note that when the clarinet is played in this way, the entire harmonic series is produced, not just the odd-numbered harmonics usually associated with the clarinet. The student might find that they are able to produce bugle calls in this manner. A former teacher of mine, Kenneth Grant, taught us this in college -- it is fun and teaches a valuable lesson!
An important point to keep in mind is that there is no ideal reed strength for the beginner, the intermediate player, or the player at any level. The proper reed strength is largely determined by the mouthpiece facing design: how open the tip of the mouthpiece is and how long the curve is. Again, it is a point for experimentation.
I suggest the use of clarinets with polycylindrical bores or reverse conical bores, and urge students to stay away from those with cylindrical bores. The first two types provide for a little more built-in air resistance and generally sound better timbre and intonation wise.
I usually recommend a medium tip opening for a mouthpiece and like the mouthpieces with a medium-long curve. Since mouthpiece preferences vary so much from region to region or town to town, it is probably best to consult a professional clarinetist in your area for specific recommendations.
Note that at the clinic, I demonstrated on a Artley 72S clarinet, with a Hite Premiere mouthpiece, Pyne 1+ barel, and Vandoren (regular cut) 3-1/2 reeds. Even with something of a mixed bag of equipment, and with an intermediate clarinet and inexpensive plastic mouthpiece, a good basic clarinet tone can be produced. I feel that we clarinetists (probably like golfers!) sometimes get too equipment oriented. By the way, my regular performance equipment is either a Buffet R-13 or Selmer 10-G clarinet and either the Pyne "JXR" or Johnston "W" (German blank) mouthpiece.
Another issue that came up in discussion with several band directors at the clinic and in informal conversation later was the problem of excessively flat pitch even when the student is using a correct embouchure, good air support, and a firm enough reed. Sometimes there are clarinet or mouthpiece problems that can cause this. I own three professional mouthpieces by a well-known maker that all have the same model designation, yet one does just what several directors described: it is more or less consistently 20 cents flat. All three mouthpieces, by the way, have about the same facing and look to be almost exactly the same length. These mouthpiece-related tuning problems are sometimes caused by the tenon joint being excessively short, causing a big gap in what should be a smooth bore transition from mouthpiece to barel. This often can't be noticed by the player unless they look inside the clarinet. Sometimes, though it is a problem with the internal dimensions of the mouthpiece. My suggestion if you have a student who is consistently flat, even with a beautiful tone, is to use a process of elimination -- what happens when he/she uses the same mouthpiece/reed combination on a different clarinet; what happens if a different mouthpiece is used on the student's regular clarinet, etc.
Probably the biggest problem we have as teachers is the balancing of all of the above areas. As shown in the clinic, some of the common tone-related playing errors can produce similar results. Fixing a sound, then, becomes a matter of eliminating possibilities. And, remember, the tendency when something is identified as a problem area, is to go overboard -- balance is everything!
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