Posted by Alex C on April 09, 2002 at 14:31:48:
In Reply to: Air Pressure / Air Flow etc posted by Jim Andrada on April 08, 2002 at 01:00:46:
Keep in mind that this wasn't Jacobs' opinion but (as all of his teaching was) based on scientific reasearch. In this case, if memory serves as a source, it was a graduate paper the CSO players participated in. The results were surprising to him, at the time.
Inter-oral pressure was measured for all of the orchestral brass instruments (each playing his own instrument), using a simple tube inserted into the corner of the mouth. (I guess they must have rejected the idea of a surgical implant.)
Flow rate was measured between the mouthipiece and leadpipe (again, if memory serves). The result was that flow rates and inter-oral pressure on the same pitch was nearly identical for all of the instrumentalists.
For the tuba player, this study helps show that extreme amounts of pressure and muscle tension are not needed and can be counter-productive.
My recollection is that the trumpet's inter-oral air pressure for high c, played at a high volume level(FF) was --- 28 OZs./psi(!). My guess is that most tuba players are hitting that pressure level and more on C two octaves lower.
Our "opinion", or our "experiences" don't help us grow as brass players if we refuse to accept such possibilities as this. The question about mouthpieces, in light of this, is really immaterial until you talk about pitches which are ledger lines above the treble clef staff.
Food for thought anyway.
Good post! Thanks.