Here's my opinion on buzzing the mouthpiece:
While recognizing that some reputable players/teachers do not reccommend buzzing, accept that some equally reputable players/teachers are staunch advocates (James Stamp, Jim Thompson and Vincent Chicowicz to name three). This is typical of brass pedagogy in general. As usual, you must check out both sides and decide for yourself.
When I buzz an accurate pitch on the mouthpiece and then slide on the horn (as suggested in Jimmy Maxwell's book), I get the identical pitch on the instrument. A great note on the mouthpiece will produce a great note on the instrument.
I feel identical whether playing a note on the mouthpiece or on the instrument. I advocate first learning to play the mouthpiece the same way as you play the horn, and then reversing that process: play the horn the way you buzz the mouthpiece. Then utilize the vibrations and slots of the horn to increase the efficiency of the buzz.
The highest note I can buzz on the mouthpiece roughly correlates to the highest note I 'own' on the instrument.
The more accurately I can buzz intervals on the mouthpiece, the more accurately I can play them on the horn.
The mouthpiece is a great revealer, both sonically and visually, of flaws in the embouchure. I've seen mouthpiece buzzing correct many bad embouchure habits.
Developing confidence in your approach to buzzing the mouthpiece helps to make the transition from horn to horn, as you are not relying on the instrument to do the job for you. It makes it easier to assess just what a given instrument is doing, making comparisons easier and more accurate.
One of the problems with buzzing that I have encountered with some students is the tendency to tighten up the embouchure too much. Buzzing the leadpipe, a la Bill Adam seems to help a great deal with this problem.
The Buzz-Aid is a great help in melding your buzzing and playing techniques. It addresses posture, mouthpiece placement, pivot and pressure, and allows you to coordinate buzzed pitches with your fingers. Following is some information on the Buzz-Aid.
The buzz-aid acts as an extension of the mouthpiece, allowing you to place it in the horn, while still buzzing normally. (It diverts the air through a hole in the side, instead of into the leadpipe). Because the horn is in your hands, you are encouraged to maintain proper playing posture. Also, you can coordinate your valve fingers with the change of pitch on the mouthpiece. (Much faulty articulation can be attributed to poor coordination between the fingers and the lips.) it may also be easier to achieve normal embouchure placement with the mouthpiece attached to the horn. Finally, some players just can't take buzzing the mouthpiece seriously enough to reap all the potential benefits. Holding the horn and fingering a passage while buzzing can provide the actual playing stimulus necessary to devote full concentration to buzzing. 'The 'gadget' aspect of the buzz-aid convinces many students, even beginners, to devote time to this valuable practice technique.
The Brass Tactics Buzz-Aid does not add any resistance to your mouthpiece. Buzzing with the buzz-aid feels essentially the same as buzzing without it. This promotes the free flow of air, so important to a clear tone. Playing a difficult passage on the buzz-aid first can help provide the feeling of blowing through the phrase, without getting hung-up on individual notes.
Consistent daily practice on the buzz-aid will provide improvement in tone, flexibility, pitch, range and accuracy of attacks. Use it to play scales, arpeggios, nursery rhymes, national anthems, lyrical phrases etc. Full mouthpiece routines can be found in books by James Stamp, Jimmy Maxwell, and of course, BRASS TACTICS.
As I continue to receive requests, I will repeat that Buzz-Aids are available from me for $10 US. Shipping is free.
You can never have too many toys.