nordlandstrompet

Don't shoot the pianoplayer. I am the responsible inventor (and exclusive owner) of "the world famous mouthpiece trick"!

I need a few points claryfied:

Proven fact: Air goes through the instrument. Inputvolume = Outputvolume

If the air inside the instrument is AC, does it move/flow a different way than if it was DC?

Why/how?

What kind of influence has the "standing waves" to the air?
Will the air "melt" and become softer/lubricated with the "standing waves" added, so it can pass through narrower points without increase of resistance?

Why are people discussing different leadpipes, round tuning slides, reverse tuning slides, valvesections when they are talking about "freer blow" aka less resistance?

Why do Taylor's Vulcan flugels and trumpets work?

"Standing waves" might also be a wrong visualization? The consept might come from how the frequencies occurs on the screen of the measuring device? I guess that the waves goes in a 360 degrees circle, but may be I don't have a clue at all....

But, I am very curious

nordlandstrompet

mrtrpt

.

tedh1951

Lads and Lassies,

I suspect we are all over-complicating the whole process. Buzzing causes the sound, big buzzing causes BIG sounds, little buzzing causes LITTLE sounds - this will also be the mechanism to vary frequency. Tubing shapes, lengths, materials, thickness, coatings etc all alter the sound output either to your liking or not - end of story (I think).

ROWUK is correct (in my opinion) in that blowing allows us simply to breathe, and to create the buzz.

BTW - standing waves are a function of supersonic airflow - that is air travelling higher than the local speed of sound and the shock wave that stands at the point where the speed of sound is achieved (a bit of a simplification). So this too is probably either a misnomer or some other concept misunderstood or "poorly" described - we certainly don't want, and are highly unlikely to achieve supersonic airflow with our breath. A sneeze, for example, gives an output of about 120 mph (from memory).

Once again, I hope this helps. Interesting thread though, keep asking questions, it staves off Alzheimers.

Regards,

Schilke player

Hvordan har du det? I know some folks that live in Fevik. Where are you?

tedh1951

Sorry All, mind in neutral again, standing waves occur in normal airflow patterns like in musical instruments, car and bike exhaust pipes and so on. Shock waves exist in supersonic airflows.

nordlandstrompet

Jeg har det bare bra!
I live on an island between Stavanger and Haugesund.
A few kilometers from the place where the viking King Harald
gathered Norway into one kingdom, and not very far
from the copper mine which delivered the copper to the Statue of Liberty!

nordlandstrompet

it staves off Alzheimers......

I could really not resist this one

tedh1951

Touche!

rowuk

standing waves occur anytime that there is oscillation due to impedance mismatch. The impedance mismatch on a trumpet comes from "imperfections" of the horn. The bell does not provide optimal coupling to the air and the mouthpiece does not provide optimal coupling to the chops/breathing apparatus. By "optimal" I mean most efficient according to horn theory. If we constructed a "perfect" horn, we probably could not play it in tune or have a sound that was considered "acceptable".