Posted: Sun Nov 19, 2023 7:44 pm Post subject: One for the physicists
To be clear: I'm not a physicist...and I'm not trying to start a wildfire here. That said, I would like to know in layman physics terms how the parameters of mouthpiece sizes (ie. cup volume, depth, etc.) influence the resulting timbral colour and volume of sound.
All I've understood from various discussions here is that 'energy in' excites various standing waves to various degrees...if that's even close to being correct(??). But wouldn't any mouthpiece do that? Is it that the parameters of the mouthpiece directly influence the resulting characteristics of the output waveforms...and therefore the resulting timbral (overtone) spectrum?
If this is more-or-less the case, then the horn is in large part more or less an amplifier? (I'm thinking power amp in hifi terms here). And the mouthpiece is more like the preamp? (with built-in 'tone controls').
Any physicists or acousticians out there?
Thx. _________________ Bach 239 C
Kanstul 700
Getzen Proteus 907S Bb
Bach Strad 37 Bb (70s)
ACB Doubler flugel
Getzen Capri cornet
Vibrations of lip aperture will include more overtones if the motion is non-sinusoidal/non-harmonic (e.g., approaching a square-shaped wave). This can be helped by reducing the depth of the mouthpiece. In the extreme case, lips will bounce away from the shallow mouthpiece surface, and the sound, rich with overtones will be very bright ("lead mouthpiece").
In contrast, a deep mouthpiece will facilitate a sinusoidal/harmonic vibration, making the sound dark (typical for flugelhorn or brass band cornet setup).
Joined: 24 Dec 2018 Posts: 3308 Location: Endwell NY USA
Posted: Mon Nov 20, 2023 6:10 am Post subject:
This is my layman's view -
Trumpet does not function as an amplifier - it 'concentrates' (not like an electric condenser) and 'refines' the air pressure vibrations to produce its sound.
Mouthpiece rim shape and inner / outer diameter affect how the rim interfaces with the players lips, and can affect how the player is able to adjust their lips. And lip positioning affects how the vibration / pulsation is produced.
The size and shape of the cup / throat / backbore affect how the vibrations get reflected and 'bounced around'. The amount of interior space acts somewhat like an automobile shock absorber of the interior pressure and how that pressure affects the lips. _________________ Most Important Note ? - the next one !
KNOW (see) what the next note is BEFORE you have to play it.
PLAY the next note 'on time' and 'in rhythm'.
Oh ya, watch the conductor - they set what is 'on time'.
If this is more-or-less the case, then the horn is in large part more or less an amplifier? (I'm thinking power amp in hifi terms here). And the mouthpiece is more like the preamp? (with built-in 'tone controls').
The instrument is a resonator, not an amplifier of any sort.
The mouthpiece properties affect the acoustics of the full instrument.
Joined: 09 Aug 2019 Posts: 409 Location: SE Louisiana
Posted: Mon Nov 20, 2023 8:09 am Post subject:
See the below link to a paper Matt Frost wrote. It’s long at 383 pages, but look through the contents and you will likely locate some information you seek.
Ron
Joined: 24 Feb 2008 Posts: 2642 Location: vista ca
Posted: Mon Nov 20, 2023 9:15 am Post subject:
I usually like what Kalifa brings to the conversation, but this one:
“ The instrument is a resonator, not an amplifier of any sort”
Seems to be a good example of something the layman can take issue with, and maybe lead to developing a bad attitude about science in general.
If you buzz a mouthpiece and then while buzzing insert that buzz into a trumpet, it gets way louder. Therefore it has to be an amplifier of SOME sort. perhaps all it does is resonate, but if its louder, it’s an amplifier of some sort.
Joined: 23 Mar 2003 Posts: 9033 Location: Hawai`i - Texas
Posted: Mon Nov 20, 2023 9:46 am Post subject:
"Would it help?" Rudolf Abel's character in "Bridge of Lies".
Just curious, why do you want to know? Are you going to start working on mouthpieces? _________________ "If you don't live it, it won't come out of your horn." Bird
I am defining ‘amplifier” as something that makes sound louder.
Amplifiers use external power not provided by the performer to increase the sound power out. He even added this context:
Quote:
(I'm thinking power amp in hifi terms here)
Adding the trumpet to a mouthpiece makes a much more efficient resonator, resulting in relatively much more output for the same air power input to a mouthpiece alone. But, sorry, still not an "amplifier".
Kehaulani asked: "Just curious, why do you want to know?"
I wuz curious whether there was any real truth to what I'd read (as opposed to opinions); and am always on the lookout for an (easily) implemented advantage to make the horns sound as good as they can. Am still not clear whether or how a larger backbore and/or throat would change the sound... _________________ Bach 239 C
Kanstul 700
Getzen Proteus 907S Bb
Bach Strad 37 Bb (70s)
ACB Doubler flugel
Getzen Capri cornet
Joined: 26 May 2006 Posts: 1808 Location: Toronto, Canada
Posted: Mon Nov 20, 2023 12:27 pm Post subject:
lipshurt wrote:
I usually like what Kalifa brings to the conversation, but this one:
“ The instrument is a resonator, not an amplifier of any sort”
Seems to be a good example of something the layman can take issue with, and maybe lead to developing a bad attitude about science in general.
If you buzz a mouthpiece and then while buzzing insert that buzz into a trumpet, it gets way louder. Therefore it has to be an amplifier of SOME sort. perhaps all it does is resonate, but if its louder, it’s an amplifier of some sort.
I am defining ‘amplifier” as something that makes sound louder.
I get your point, but I think there's a good reason for kalijah's distinction here. As many teachers and theorists have demonstrated, you can release air through your lips and into the mouthpiece while in the playing position and not get any sound at all, but once that airstream meets the resistance of the trumpet, a trumpet tone results. The trumpet is not functioning as an amplifier here - there was no sound to amplify until the trumpet entered the equation. Good playing is (consciously or not) about working with the physics of the instrument, and treating it as something that makes mouthpiece buzzing louder (IE - where you buzz the mouthpiece first and plug that same input into the trumpet) is wasting a ton of energy, and compromising the quality of the output.
Another distinction is that an amplifier would ideally have a "flat" frequency response. Showing no favoritism of amplified frequency. Obviously not a quality of the instrument.
The resonator, in this case the trumpet has very distinct, defined and STRONG resonances. A quality that would be a nightmare for an actual sound power amplifier but is essential to the trumpet or any brass instrument.
Joined: 12 Feb 2004 Posts: 6130 Location: Des Moines
Posted: Mon Nov 20, 2023 2:57 pm Post subject:
William Adam did a behind the screen session where he played excerpts ranging from Brahms to Brandenburg to Beethoven. Everyone was gassed at how great he sounded on all of the excerpts. He played them all on a Bb trumpet and one mouthpiece. Draw your own conclusions. _________________ Bill Bergren
Joined: 16 Jul 2004 Posts: 1102 Location: Sacramento, Ca
Posted: Mon Nov 20, 2023 3:46 pm Post subject: Re: One for the physicists
Proteus wrote:
To be clear: I'm not a physicist...and I'm not trying to start a wildfire here. That said, I would like to know in layman physics terms how the parameters of mouthpiece sizes (ie. cup volume, depth, etc.) influence the resulting timbral colour and volume of sound.
All I've understood from various discussions here is that 'energy in' excites various standing waves to various degrees...if that's even close to being correct(??). But wouldn't any mouthpiece do that? Is it that the parameters of the mouthpiece directly influence the resulting characteristics of the output waveforms...and therefore the resulting timbral (overtone) spectrum?
If this is more-or-less the case, then the horn is in large part more or less an amplifier? (I'm thinking power amp in hifi terms here). And the mouthpiece is more like the preamp? (with built-in 'tone controls').
Not exactly in "layman's" terms, but the information is explained well with graphs and diagrams to show the timbral differences occurring when various mouthpiece parameters are changed. It also covers the effects on intonation which has been a big help, at least for me, in selecting mouthpieces for different instruments. _________________ -Tom Hall-
"A good teacher protects his pupils from his own influence."
-Bruce Lee
Joined: 24 Feb 2008 Posts: 2642 Location: vista ca
Posted: Sun Nov 26, 2023 10:08 am Post subject:
“The trumpet is a resonator, not an amplifier of ANY SORT”
Come on, the trumpet makes the mouthpiece louder. If it’s louder, it’s been amplified. It’s crazy to say that it has not been amplified. It’s an amplifier of SOME SORT.
How hard is that to wrap your head around?
Resonator:
“ A resonator is a device or system that exhibits resonance or resonant behavior. That is, it naturally oscillates with greater amplitude at some frequencies, called resonant frequencies”
Joined: 24 Dec 2018 Posts: 3308 Location: Endwell NY USA
Posted: Sun Nov 26, 2023 10:26 am Post subject:
lipshurt wrote:
... It’s an amplifier of SOME SORT. ...
---------------------------
The 'trumpet sound' is louder to our ears, but there is not any additional 'physics energy' beyond what the player is producing.
In technical writing, an amplifier produces more 'output energy' than the 'input energy' - and consumes more energy to operate the amplifier than the amount of additional energy it produces. _________________ Most Important Note ? - the next one !
KNOW (see) what the next note is BEFORE you have to play it.
PLAY the next note 'on time' and 'in rhythm'.
Oh ya, watch the conductor - they set what is 'on time'.
Joined: 26 May 2006 Posts: 1808 Location: Toronto, Canada
Posted: Sun Nov 26, 2023 2:11 pm Post subject:
lipshurt wrote:
“The trumpet is a resonator, not an amplifier of ANY SORT”
Come on, the trumpet makes the mouthpiece louder. If it’s louder, it’s been amplified. It’s crazy to say that it has not been amplified. It’s an amplifier of SOME SORT.
How hard is that to wrap your head around?
So, does that mean that a bathroom is also an amplifier for shower singing?
Joined: 03 May 2005 Posts: 8951 Location: Monument, CO
Posted: Mon Dec 04, 2023 6:56 am Post subject:
The trumpet is not an amplifier. The trumpet resonates at certain frequencies, making it easier for the energy to be concentrated at those frequencies Power (energy) comes from the player. Despite what we may feel, neither the trumpet itself nor the mouthpiece add any energy to the system; some is necessarily lost through the instrument. The mouthpiece and horn help concentrate and focus the energy through resonance and dispersion control.
Your water hose and nozzle is not an amplifier either, though you might think so when you constrain the nozzle's aperture so the stream narrows and shoots farther. All the energy for the system is from the water source, nothing is added and in fact some is lost through the hose and nozzle.
Physics is often at odds with what people "know" by observation. _________________ "After silence, that which best expresses the inexpressible, is music" - Aldous Huxley
Last edited by Don Herman rev2 on Mon Dec 04, 2023 8:04 am; edited 1 time in total
Also, if the trumpet were an amplifier of the mouthpiece only, then the tone would sound like a buzzed mouthpiece but louder and its "amplification" would be consistent regardless of the pitch played.
A typical trumpet with 3 valves is actually seven resonators. (or technically eight)
Quote:
Physics is often at odds with what people "know" by observation.
A poster once wrote that he checked my explanation with a competent physics expert he knew. He now disagrees with both of us.
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