A Conversation for Trumpets
babelhorn Started conversation Jan 9, 2004
The above harmonics entery is essetially true. As always the description of tightening the lips has always evoked the question "why" everyone seems to gloss over that bit of information.
So here is an explanation. And even though I think it is a revealing and helpful thought when I'm through you can still justly ask the question why.
Sound is energy that acts very much like five suspended balls that click back and forth when the end ball whacks the still balls and throws out the opposite end ball. Kinetic energy of sound propagates by the sound source banging air molecules together. No problems here. The trouble starts when we begin to discus the kind of energy that precedes the kinetic energy or when we "Wind" an instrument. My middle school students have always delighted in offer their theories on winding and instrument with astonishingly creative zeal. Even a few of my recent university students have stifled conjectures that I felt would have been just as entertaining.
OK here comes the prickly part: As you know the trumpet is a static instrument – it does nothing. We have to be the energy source, READ MY ENTRY HERE IS AN IDEA. Or RASP MY ASP.
Basically I’m saying that through winding the horn and accelerating the air with the help of the venturi tube we excite the air column defined by our trumpet and create a standing wave. Centrally to this discussion on harmonics when we tighten our lips this is what happens:
The embouchure really only focuses the air identically to the way a flute player focuses the air. Our embouchure plays the most important role in increasing or decreasing the intensity of our air stream or air velocity. A faster more excited air stream excites higher harmonics or higher frequencies. You must agree that the terms High Low are misleading. Sound frequencies are really understood in terms of Fast and Slow vibrations.
The horn (tube) length and shape literally discriminate against all other frequencies that are not appropriate for its length.
The point is that blowing hard will give you and your listeners a headache. Controlling the velocity of the air will free up your playing and give the listeners something pleasant to listen too.
It is most helpful for trumpet players to think of faster air rather than harder air. Give this a try and then as soon as possible dump all of this theory out of your head and think – imagine your most beautiful sound and let your mind dwell there as you play music.
Gnomon - time to move on Posted Jan 12, 2004
Your theory and mine are virtually identical, Babelhorn. Standing waves and all that are standard acoustical theory which I didn't bother to explain in the entry as I felt they were too technical. The only point we disagree on is whether the lip vibration is the cause or the result of the sound.
My understanding is that you need a noise generator, which produces sound of all frequencies. Those frequencies which are of the correct wavelength to cause standing waves resonate with the air in the tube. Those frequencies which aren't are supressed by the tube. In flutes and recorders, the noise is generated by the hard edge (labium). In clarinets and oboes, it is by the vibrating reed. In brass instruments, there are no sharp edges, so the lips are used.
babelhorn Posted Jan 14, 2004
I am out of my league as we go into woodwinds. I would humbly admit that even the descriptions of the brass extend my analytic abilities to the max. In the acoustical physics articles I have read I am absolutely pressed to the limit by the math. Working and developing an understanding of these principles has be a long and difficult task. From the best of my understanding (admitting humbly to you that I am not a scientist) all reeds in modern instrument vibrate in sympathy with the standing wave with in the musical instrument. PLEASE before you retort read the article in Scientific America.
This I know for a fact; when a student of the trumpet has a sound in their head they will achieve it. As teachers we need to direct them to the most useful and musical sounds possible. The sounds that are functional and musical come from a symbiosis between the player and their instrument. When anyone trys to force a tone (loud or Soft) the get into trouble. Allowing this to work freely and unhindered is my greatest goal as an instrument instructor. Getting your head into this kind of thinking is extremely helpful for wind musicians.
By the way thanks for not ragging on my poor use of punctuation and sloppy editing of homonyms.
Gnomon - time to move on Posted Jan 14, 2004
You're right about the reed vibrating in sympathy with the standing wave in the pipe. This is the case for all woodwinds that use a reed, but not for reed pipes in organs, where the reed is stronger, usually made of metal and vibrates at a frequency partially determined by the size of the reed itself. In free reed instruments such as the accordion, there is no pipe at all, and the frequency is entirely determined by the dimensions and rigidity of the reed.
Can I get that article from Scientific American on line anywhere?
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