Instrument=Amplifier or resonator ?
- Doug Elliott
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Re: Instrument=Amplifier or resonator ?
There are lots of different ways and configuratons of lip and teeth positions that can make your lips buzz, with or without the mouthpiece or horn, or create the necessary standing wave. Those kinds of demonstrations can show any point of view, for or against buzzing.
"I know a thing or two because I've seen a thing or two."
- harrisonreed
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Re: Instrument=Amplifier or resonator ?
If nothing else they serve to prove the point that you make often, something to the effect that you can practice buzzing the wrong way which is not helpful to the player, possibly to the detriment of the player.Doug Elliott wrote: ↑Thu Feb 29, 2024 3:02 pm There are lots of different ways and configuratons of lip and teeth positions that can make your lips buzz, with or without the mouthpiece or horn, or create the necessary standing wave. Those kinds of demonstrations can show any point of view, for or against buzzing.
- Wilktone
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Re: Instrument=Amplifier or resonator ?
It's not that I don't get Bergeron recommends against mouthpiece buzzing, it's all the other stuff he says that don't really address why. I mentioned my gripes with his demonstration earlier, and I agree with Doug's point that you can do these party tricks in different ways to say whatever you feel like.musicofnote wrote: ↑Thu Feb 29, 2024 2:47 pm So if two understood what he was on about, and one didn't, I don't think it was because Mr. Bergeron didn't somehow explain it clearly enough...
i don't want to go into it any deeper than that, because it's not about me and what I think or do. I just found it interesting, that another top player isn't a buzzer.
For the record, I really don't utilize mouthpiece buzzing in my own practice or teaching. There are a couple of situations where I find mouthpiece buzzing to be helpful, but my goal is usually to get away from that as quickly as possible. I think you can make your mouthpiece buzz and playing embouchure function very close to each other and get some value from it, but personally find it's better to get those results by practicing things on the horn.
Like Harrison reminded us, practicing things incorrectly, even stuff that is known to be helpful, can make things harder.
Speaking of Bergeron's demonstration, I had another thought about it earlier today.
If we just open our lips and blow, it feels like there's a lack of resistance. If we do the same thing on a mouthpiece, without forming an embouchure, we feel more resistance. Blow into the whole instrument similarly, there's even more. So when we blow air into the mouthpiece and then slot it into the instrument, I don't think it's the standing wave (which hasn't started yet) that makes the lips start to vibrate. It's probably more related to the increased resistance of the entire instrument.
Try blowing into your mouthpiece and then use your finger to cover up some of the shank to increase the resistance. Do you end up getting a mouthpiece buzz?
Dave
- BGuttman
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Re: Instrument=Amplifier or resonator ?
If I'm badly out of practice I can't get a buzz on the mouthpiece without the finger to increase resistance. When I'm in practice and playing at my usual level I don't need the finger.
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Re: Instrument=Amplifier or resonator ?
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- harrisonreed
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Re: Instrument=Amplifier or resonator ?
With respect to you, and as a fellow anti-buzzer, there are some cases where you should definitely interrupt someone when you don't think it can be done :musicofnote wrote: ↑Fri Mar 01, 2024 12:24 am Before anyone wants to say it can't be done, please read my signature.
https://en.m.wikipedia.org/wiki/Franz_Reichelt
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Re: Instrument=Amplifier or resonator ?
Dave, this is what I've been saying for nearly a decade now, since I figured it out for myself. The standing wave and the resistance from the instrument are nearly the same thing. The standing wave is just the horn's natural resistance (the air inside of it that has no where to go except out the bell) after it's been energized. Once energized, it will feel like more resistance, because the standing wave will have regular intervals of increased compression. It's been shown many times that the air in such a tube will vibrate as a standing wave just by blowing air into it with enough force, lips or no. Do the lips and oral cavity have an effect on the sound? Yes of course they do. But active buzzing without the resistance of the standing wave is training the exact opposite of locking into the slot and letting the horn do it's job.Wilktone wrote: ↑Thu Feb 29, 2024 9:08 pm
If we just open our lips and blow, it feels like there's a lack of resistance. If we do the same thing on a mouthpiece, without forming an embouchure, we feel more resistance. Blow into the whole instrument similarly, there's even more. So when we blow air into the mouthpiece and then slot it into the instrument, I don't think it's the standing wave (which hasn't started yet) that makes the lips start to vibrate. It's probably more related to the increased resistance of the entire instrument.
Dave
You mention putting your finger over the shank to increase the resistance, too, in order to get a more natural buzz on the lips. Plus everything above. You should just take the last, tiny, 1cm step and join the folks who look at all that and realize for themselves that there is no "correct" way to buzz without the resistance of the horn.
Obviously, even saying all that, people can buzz without it harming their playing. So many great players do it. I just don't know what it is that they are actually training or improving with the practice.
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Re: Instrument=Amplifier or resonator ?
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Re: Instrument=Amplifier or resonator ?
I’m rather new to a lot of the theory that’s being spoken about here, but this makes perfect sense. My first band director was a clarinet player and pushed free buzzing which produce a dying duck sound for me (and I say for me only in this post). The closest thing I have had to a trombone instructor was my father. He taught me the opposite, to form the embouchure, and then blow into the mouthpiece. The pressure of the mouthpiece then created the buzzing of the lips. Moving the air in the mouthpiece would then change the note. Maybe this is incorrect, I don’t know. I’m sure private lessons will help me as I continue to learn, but I know my sound and clarity improved greatly when I stopped fighting the horn.harrisonreed wrote: ↑Fri Mar 01, 2024 5:56 am
You mention putting your finger over the shank to increase the resistance, too, in order to get a more natural buzz on the lips. Plus everything above. You should just take the last, tiny, 1cm step and join the folks who look at all that and realize for themselves that there is no "correct" way to buzz without the resistance of the horn.
Getting back to what harrisonreed said, I have never tried to put my finger over the end of the shank to see what resistance would do for the buzzing sound. I know when I hold the mouthpiece at the cup, I get a horrible sound, but when I wrap my hand around the shank only, I can buzz and it sounds significantly better and I can hit ‘notes’ so to say…I will try this with the finger alone cause I’m really interested in this. Thank you to you all for your varied knowledge in this post, it is definitely opening my eyes to a lot of things and making me pay more attention to what my body is doing while playing!
- Wilktone
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Re: Instrument=Amplifier or resonator ?
musicofnote, I feel like we're discussing different things. I believe and agree with you that time spent mouthpiece buzzing is (usually) better spent practicing something different. Perhaps where I diverge from your opinion is that I think it *can* be done in a way that is beneficial, just that it takes enough effort that I personally don't think it's really worth my time.musicofnote wrote: ↑Fri Mar 01, 2024 12:24 am Again, if two people "got it" from once through the video, then it's not Bergeron's fault for not explaining it.
It would appear he's not giving you the rfeasoning you're expecting, which is not surprising. But it just what other "non-buzzers" have said and demonstrated. . .
Before anyone wants to say it can't be done, please read my signature.
What I am pushing back on is the rational that Bergeron (and others) provide for their opinions. It doesn't seem credible to me so I don't get how it relates to his point on buzzing. That doesn't mean the conclusions he's drawing is wrong, but if it's based on a false premise, I think it should be examined a little more carefully. There's a lot more nuance that he's not taking into account and the devil is in the details.
I don't believe you.harrisonreed wrote: ↑Fri Mar 01, 2024 5:56 am The standing wave and the resistance from the instrument are nearly the same thing.
Yes, as the standing wave is set up the lips should vibrate in tandem with it. Yes, it sound better when it does. Yes, it's easier to play when the body is working with the standing wave. Those points are correct.
In order for the standing wave to be formed it *must* be first activated at the lips. The lips have to open and close at least a couple of times in order to set up how many nodes are formed on the standing wave and what partial gets played. There is no way the standing wave knows without the player's lips (and other playing factors) telling the standing wave to play a low Bb or a high F first. The resistance of the instrument doesn't change on it's own to change pitches.
The Leno film I embedded in the last page shows the players' lips taking a split second to adjust to the proper frequency as they slur across partials. It is the buzzing of the lips that activates the standing wave, not the other way around.
No, I mentioned trying the finger over the shank as a way to recreate Bergeron's demonstration.harrisonreed wrote: ↑Fri Mar 01, 2024 5:56 am You mention putting your finger over the shank to increase the resistance, too, in order to get a more natural buzz on the lips
For those of us who didn't watch the video or forgot, Bergeron demonstrated blowing air into his mouthpiece and then slotting his trumpet over the mouthpiece. When doing so the standing wave got active and there was a trumpet tone. Bergeron explicitly states (2:27) "We don't want to make the vibration first, we want this to happen..." and "The sound is not starting until I add resistance."
Adding resistance after already blowing in the mouthpiece with a finger over the shank starts the sound, just like slotting the mouthpiece into the instrument. Again, the lip vibration *must* vibrate before a pitch sounds, even on the mouthpiece.
I'm really not defending mouthpiece buzzing. I do advocate free buzzing (with embouchure form that closely relates to the form while playing the instrument).harrisonreed wrote: ↑Fri Mar 01, 2024 5:56 am You should just take the last, tiny, 1cm step and join the folks who look at all that and realize for themselves that there is no "correct" way to buzz without the resistance of the horn.
But the arguments for practicing either are specifically *because* they remove the resistance of the instrument and the influence of the standing wave. Sure, it's not "correct" in the sense that playing the instrument requires the interaction with the standing wave. It's not "correct" for a baseball player to attach weights to the bat and practice swinging, but it apparently helps them hit balls further (I guess, I don't know baseball, that was the analogy I happened to think of).
The reason why *I* discourage mouthpiece buzzing isn't because the lips aren't interacting with the standing wave. It's because the way most people mouthpiece buzz is with an embouchure formation that doesn't work well on the horn (usually too open, lips blown too far inside the mouthpiece). *That* is what Bergeron is actually demonstrating when he buzzes on the mouthpiece and then slots it into the trumpet. All the talk about standing waves and how that's the big difference is a false premise.
Dave
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Re: Instrument=Amplifier or resonator ?
Might be helpful to add Bernoulli to the discussion. The air rushing between the open lips creates low pressure that "sucks" lip tissue into it, which elastically rebounds and repeats, creating a frequency. (I think Dave has before posted video that seems to show waves of flesh in an open aperture.)
It may be that Wayne's demonstration shows that the initial conditions required for mouthpiece buzz in this way are different from that required for horn buzz. So, his horn buzz may not mouthpiece buzz without the influence of the horn. And he may be showing that applying mouthpiece conditions to the horn results in a poorer sound.
If that's the case, then the disputes about how the buzz works make perfect sense to me. I'm pretty sure in all cases it is Bernoulli who will apply, but it may be initial conditions that make for the difference of opinion and understanding of experience.
It may be that Wayne's demonstration shows that the initial conditions required for mouthpiece buzz in this way are different from that required for horn buzz. So, his horn buzz may not mouthpiece buzz without the influence of the horn. And he may be showing that applying mouthpiece conditions to the horn results in a poorer sound.
If that's the case, then the disputes about how the buzz works make perfect sense to me. I'm pretty sure in all cases it is Bernoulli who will apply, but it may be initial conditions that make for the difference of opinion and understanding of experience.
- Doug Elliott
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Re: Instrument=Amplifier or resonator ?
If anyone truly believes that air going through the horn produces a standing wave with or without the lips, I invite you to put your lips AROUND the mouthpiece and blow.
It doesn't matter how soft or hard you blow, you're not going to get a standing wave.
It doesn't matter how soft or hard you blow, you're not going to get a standing wave.
"I know a thing or two because I've seen a thing or two."
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Re: Instrument=Amplifier or resonator ?
This guy does just that. It sounds terrible. The end is also not sealed off by lips. Not sure if it's proof or not, but he seems to think it is.
He concludes, however, that the buzzing lips are the cause of the standing wave.
- Doug Elliott
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Re: Instrument=Amplifier or resonator ?
"The end is also not sealed off by lips. "
Which means it's NOT a closed end tube and it's not resonating as one.
Details, details...
He says the sound is the fundamental. Which?
A closed end tube and an open tube have very different fundamentals.
He either doesn't know the difference or he's ignoring it.
Which means it's NOT a closed end tube and it's not resonating as one.
Details, details...
He says the sound is the fundamental. Which?
A closed end tube and an open tube have very different fundamentals.
He either doesn't know the difference or he's ignoring it.
"I know a thing or two because I've seen a thing or two."
- Wilktone
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Re: Instrument=Amplifier or resonator ?
Exciting the standing wave requires an oscillator. Our lips function in this capacity for normal playing. In Spellman's demonstration he's using fire as an oscillator. There are mechanical oscillators that have been designed to use with brass instruments too.harrisonreed wrote: ↑Fri Mar 01, 2024 1:08 pm
This guy does just that. It sounds terrible. The end is also not sealed off by lips. Not sure if it's proof or not, but he seems to think it is.
He concludes, however, that the buzzing lips are the cause of the standing wave.
But it's the oscillator that excites the standing wave in the first place, not the other way around.
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Re: Instrument=Amplifier or resonator ?
Yes there definitely is a difference in the way a tube open on both ends works vs one end sealed. I'm out of my depths here, I'm finding
- LeTromboniste
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Re: Instrument=Amplifier or resonator ?
This is not really germane to the broader discussion, but...Cylindrical closed-open pipe overblows at the 12th (i.e. only has the odd harmonics) and has a fundamental an octave lower than an open pipe of the same length. We get taught as trombonists that our partials correspond to the harmonic series (down to certain partials being a certain number of cents sharp or flat because that's how they are in the harmonic series), but that's actually not true. The reason we actually get partials that fit the harmonic series of a 9' open pipe is because the bell flare and the mouthpiece combine to shift and "compress" the partials. They are originally far off from that, but the bell and mouthpiece change them to (artificially) approximate the harmonic series. The true fundamental mode of our instrument is different than the pedal tones and is never actually used because it's not shifted anywhere near enough. Pedal tones are the result of the rest of the modes of resonance (which do roughly correspond to the overtones of the pedal note you're trying to play) forcing the production of a standing wave despite there being no actual mode of resonance at that frequency, mixed in with some psychoacoustics (our brains want to hear the fundamental because the overtones imply its presence and we "know" it's there even when it's not actually really there). That's why pedals on a cylindrical brass instrument feel and sound somewhat different than the rest of the notes, and why the same can't be said of true conical instruments.harrisonreed wrote: ↑Mon Mar 04, 2024 10:02 am Yes there definitely is a difference in the way a tube open on both ends works vs one end sealed. I'm out of my depths here, I'm finding
Back on the main topic, to some extent, this discussion feels to me a bit to-may-toe/to-mah-toe. It's both an amplifier and a resonator (and a filter). Clearly the horn is not just amplifying the buzz (or else you could play any note in any position and we wouldn't have a slide), it's amplifying the resonance. But whether or not we want to think conceptually about our playing technique in terms of active buzzing vs. passive buzzing (i.e. the lips only vibrate because air rushes past and/or because of the resistance of the instruments) – which I think can both be valid approaches – physically what happens at the interface and beyond is that there still is a buzz happening, it's still being filtered by the instrument, excites the standing wave (which in turns contributes into bringing the lips into a more stable buzz) and that standing wave is the sound we hear.
TL;DR: I agree with David:
The discussion as it pertains to how we play is worthwhile, but not because of whether our instrument is a resonator or an amplifier.All the talk about standing waves and how that's the big difference is a false premise.
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Re: Instrument=Amplifier or resonator ?
Maximilien,LeTromboniste wrote: ↑Tue Mar 05, 2024 7:28 amThis is not really germane to the broader discussion, but... ... pedals on a cylindrical brass instrument feel and sound somewhat different than the rest of the notes, and the same can't be said of true conical instruments.harrisonreed wrote: ↑Mon Mar 04, 2024 10:02 am Yes there definitely is a difference in the way a tube open on both ends works vs one end sealed.
...
TL;DR: I agree with David:The discussion as it pertains to how we play is worthwhile, but not because of whether our instrument is a resonator or an amplifier.All the talk about standing waves and how that's the big difference is a false premise.
Thanks for the physics lesson!
- Doug Elliott
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Re: Instrument=Amplifier or resonator ?
Yes, all correct and exlained very well. Thanks!
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Re: Instrument=Amplifier or resonator ?
I believe, after messurments and experiments with conical and cylindrical tubes of different lenght, that the differenc is not exactly an octav but a major 7th.LeTromboniste wrote: ↑Tue Mar 05, 2024 7:28 am
This is not really germane to the broader discussion, but...Cylindrical closed-open pipe overblows at the 12th (i.e. only has the odd harmonics) and has a fundamental an octave lower than an open pipe of the same length. We get taught as trombonists that our partials correspond to the harmonic series (down to certain partials being a certain number of cents sharp or flat because that's how they are in the harmonic series), but that's actually not true. The reason we actually get partials that fit the harmonic series of a 9' open pipe is because the bell flare and the mouthpiece combine to shift and "compress" the partials. They are originally far off from that, but the bell and mouthpiece change them to (artificially) approximate the harmonic series. The true fundamental mode of our instrument is different than the pedal tones and is never actually used because it's not shifted anywhere near enough. Pedal tones are the result of the rest of the modes of resonance (which do roughly correspond to the overtones of the pedal note you're trying to play) forcing the production of a standing wave despite there being no actual mode of resonance at that frequency, mixed in with some psychoacoustics (our brains want to hear the fundamental because the overtones imply its presence and we "know" it's there even when it's not actually really there). That's why pedals on a cylindrical brass instrument feel and sound somewhat different than the rest of the notes, and why the same can't be said of true conical instruments.
But a very post Maximilien!
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Re: Instrument=Amplifier or resonator ?
It's theoretically exactly an octave, but then in the real world, indeed, you have the effect of the bore shape and its size relative to length that cause inharmonicity, plus any conicity in the tube also skews things, so it winds up not being quite a full octave.
For anyone who's unconvinced of that concept, just look inside an organ. The stopped pipes are about half as long as the open pipes for the same pitch. And for small portable organs, you basically never have a principal 8' register that doesn't switch to stopped pipes for the basses or share the bass pipes of the bourdon, because you can't fit 8-foot-long pipes in that space. Switching to stopped pipes gets you the notes you need using only half the space.
Maximilien Brisson
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Hfk Bremen/University of the Arts Bremen
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Hfk Bremen/University of the Arts Bremen
- Wilktone
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Re: Instrument=Amplifier or resonator ?
Thanks for posting that, Maximilien. Here's a web resource that goes over the mouthpiece and bell effect on brass overtone series in some detail.
http://hyperphysics.phy-astr.gsu.edu/hb ... rassa.html
Regardless, I call "shenanigans" on Bergeron's demonstration of blowing air into the mouthpiece and then slotting the instrument and getting a tone. Contrary to what he is suggesting, there is no standing wave happening until the buzz starts it. You can't get the feedback loop from the instrument to the lips until the lips are already vibrating. That is the point I was hoping to get across.
Dave
http://hyperphysics.phy-astr.gsu.edu/hb ... rassa.html
Yes, thank you for pointing that out. "False premise" is perhaps not the best term here, "red herring" might be better.LeTromboniste wrote: ↑Tue Mar 05, 2024 7:28 amThe discussion as it pertains to how we play is worthwhile, but not because of whether our instrument is a resonator or an amplifier.All the talk about standing waves and how that's the big difference is a false premise.
Regardless, I call "shenanigans" on Bergeron's demonstration of blowing air into the mouthpiece and then slotting the instrument and getting a tone. Contrary to what he is suggesting, there is no standing wave happening until the buzz starts it. You can't get the feedback loop from the instrument to the lips until the lips are already vibrating. That is the point I was hoping to get across.
Dave
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Re: Instrument=Amplifier or resonator ?
Well, this is unimportant, but I think you get standing waves all the time. Even with no lips, as long as there is noise in the environment. That noise will enter one end or the other, travel the length, reflect off the open or closed end, return and repeat, and along the way it will be comb filtered by the overtone series in effect, either open or closed ended. Without new input, the waves will decay. You can actually hear these by holding your horn to your ear, like listening to the sea in a large spiral shell. Try pointing the bell to the white noise of traffic.
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Re: Instrument=Amplifier or resonator ?
Baileyman is right. You need some source of vibration to get standing waves. Whether vibrating lips or a rubber diaphragm "lip simulator", a bassoon reed and bocal, or even a pitch fork. The instrument has multiple functions based on your source of vibrations and its construction. The net result is a nice trombone tone (or maybe a sound like a wounded moose if that's what you play like). Resonator? Amplifier? Machts nicht.
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Re: Instrument=Amplifier or resonator ?
Again, I realize that a trombone has one end closed by your face, but in a general sense you do not need a source of vibration to get a standing wave. You just need moving air.
There is much more going on in the production of a tone on a brass instrument than just buzzing into it like you would free buzz, and obviously more to it than just blowing air into it.
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Re: Instrument=Amplifier or resonator ?
You do need a source of vibration. Just air moving won't do it if it's not also vibrating.harrisonreed wrote: ↑Wed Mar 06, 2024 11:42 amAgain, I realize that a trombone has one end closed by your face, but in a general sense you do not need a source of vibration to get a standing wave. You just need moving air.
There is much more going on in the production of a tone on a brass instrument than just buzzing into it like you would free buzz, and obviously more to it than just blowing air into it.
In that experiment, I would think just going through that mesh is probably enough to make the air vibrate. That or the air that's rushing in because of the void created does so in a way that causes friction at the entrance of the pipe (like a flute player creates vibration, or when you blow into a bottle – if you just blow straight into a bottle, you'll get some sound, but it will be the sound of air moving and bouncing around, no standing wave, but if the air hits the bottle opening at the proper angle, the friction thus created causes vibration, and voilà, standing wave).
Last edited by LeTromboniste on Thu Mar 07, 2024 7:54 am, edited 1 time in total.
Maximilien Brisson
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Lecturer for baroque trombone,
Hfk Bremen/University of the Arts Bremen
www.maximilienbrisson.com
Lecturer for baroque trombone,
Hfk Bremen/University of the Arts Bremen
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Re: Instrument=Amplifier or resonator ?
The organ pipes are open or closed. If you compare brassinstrument with cylindrical tubes the same lenght, both blown as lip reed instruments the differnce is a major seventh. A big differnce from the organ pipes is that both the cylindrical tub and the trombone are closed pipes, the conical part of the trombone makes the standing wawes shorter, not to a full octav though.LeTromboniste wrote: ↑Wed Mar 06, 2024 5:08 amIt's theoretically exactly an octave, but then in the real world, indeed, you have the effect of the bore shape and its size relative to length that cause inharmonicity, plus any conicity in the tube also skews things, so it winds up not being quite a full octave.
For anyone who's unconvinced of that concept, just look inside an organ. The stopped pipes are about half as long as the open pipes for the same pitch. And for small portable organs, you basically never have a principal 8' register that doesn't switch to stopped pipes for the basses or share the bass pipes of the bourdon, because you can't fit 8-foot-long pipes in that space. Switching to stopped pipes gets you the notes you need using only half the space.
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Re: Instrument=Amplifier or resonator ?
Subtle nitpick. The physical length of the tube is not necessarily the same as the length the sound wave reflects from. There is an edge effect. And without looking it up, I'm pretty sure it varies with frequency.
A sound wave will reflect at least partially from any impedance mismatch.
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Re: Instrument=Amplifier or resonator ?
You are rigth, Tim, it does varie with frequency. Maybe I will do another thread on this subject, it really does not belong in this thread.timothy42b wrote: ↑Thu Mar 07, 2024 8:35 amSubtle nitpick. The physical length of the tube is not necessarily the same as the length the sound wave reflects from. There is an edge effect. And without looking it up, I'm pretty sure it varies with frequency.
A sound wave will reflect at least partially from any impedance mismatch.
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Re: Instrument=Amplifier or resonator ?
delited
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Re: Instrument=Amplifier or resonator ?
Recorder technique requires the knee stop for some notes, and it's quite dangerous to the teeth. When I played more recorder I wished someone would invent a trigger key to close that end.
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Re: Instrument=Amplifier or resonator ?
I'm sure you meant conical.
I think there's math for a shape that will resonate vs amplify, thinking about old skool megaphones. Though in speakerland, any bounded shape around and in front of the driver changes how it couples to the air and thus its sound. So I'm not sure.
Some time I will post a little bit on bent pipes, which seem like they may be very interesting.
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Re: Instrument=Amplifier or resonator ?
Olofson wrote: ↑Thu Jun 27, 2024 4:09 am Well, since this thred is dead anyway, (I think) I like to ad a comment on the experiments on conical and cylindrical tubes. First, the tub can be closed or open (open means both ends are open, closed means one end is open the other closed) when the trombone, clarinett, saxophon, are played the instrument it is said to be closed (open-closed) when a flute is played it is open (open-open). When some organ pipes are played they are open or closed. When an cylindrical organ pipe is closed it is sounding one octave lower then when it is open. The clarinett is closed and cylindrical when played, the saxophone is closed and conical,according to the length the lowest tone on saxophone and clarinett are different. Also the harmonics line up differently when overblown from the lowest tone of the instrument. A fench horn is usually played closed (open closed) sometimes the horn is played "stopped" with the hand, if the hand stopped very effectly (closed-closed) the acts as being one semitone higher. In all of this cases this instrument are resonators. A amplifier is not dependent of the standing wave. You can easilly do the closed-closed effect on the trombone with a plunger when you close it effectly to the bell. It works especially good on a sackbut. When a flute is closed (with a knee or sombodys helping hand) the lowest tone dropp one octave, and the harmonics line up differntly. Sorry for ranting.
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Re: Instrument=Amplifier or resonator ?
Thankyou baileyman!baileyman wrote: ↑Thu Jun 27, 2024 9:12 amI'm sure you meant conical.
I think there's math for a shape that will resonate vs amplify, thinking about old skool megaphones. Though in speakerland, any bounded shape around and in front of the driver changes how it couples to the air and thus its sound. So I'm not sure.
Some time I will post a little bit on bent pipes, which seem like they may be very interesting.
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Re: Instrument=Amplifier or resonator ?
Yes a knee is nice for stopping. Since the recorder is conical it won´t be an octave difference. I mitgh try that some time.timothy42b wrote: ↑Thu Jun 27, 2024 7:20 amRecorder technique requires the knee stop for some notes, and it's quite dangerous to the teeth. When I played more recorder I wished someone would invent a trigger key to close that end.
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Re: Instrument=Amplifier or resonator ?
Bends are weird.
To the flow of air or any fluid, they look like additional resistance. When you're calculating pump power requirements you add up the resistances of all the pipe, valves, bends, etc.
But to the flow of sound, they look like a wide spot in the tube.
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Re: Instrument=Amplifier or resonator ?
Oh that's interesting. Bach might have gone the wrong direction then putting large slibe bows on small tubes.timothy42b wrote: ↑Fri Jun 28, 2024 8:16 am ...
But to the flow of sound, they look like a wide spot in the tube.