Tuba tactics and false news.

[Donn]

One "?" isn't cause for any concern, it's when they start to pile up, or "pile on" maybe. Tubenet can come off like a gang of adolescent boys sometimes.

I personally thought the "large bells and huge bore tubas are deceptive" argument was way off the mark,

the "trombone bell material, plating etc made no difference" likely correct for the audience, and

"this venturi nonsense" we're innocent - that's trumpet players, isn't it?

[The Brute Squad]

I guess the partial anonymity of the Internet still affects some people so that they don't care about details.

The Greater Internet (bleep)wad Theory still holds true 15 years later.

[Matt G]

A thicker bell will be able to withstand higher volumes, but at the same time will in some ways be deader "feeling" than a thinner one.

As mentioned above, shape is the determining factor. A while back (probably over a decade ago) it was put forth that the bell shape alters the critical point for the impedance change that governs the resonating air column.

I also think that the reason the rapid taper bells often come with pitch quirks is that the impedance change region is sort of "locked in" to one harmonic series whereas a stovepipe bell has some wiggle room (the gradient of impedance change is less).

This could also be made up.

[Donn]

Our Original Poster comments about what I think is that same impedance effect, in another thread:

Yes, that bell width does make a big difference. The sound is, yes, ‘broader’ to our ears for good reason. The larger bore in last few yards also has an effect. And this not just because we imagine the difference.

The bell and the leadpipe control the physics as follows:

The vibration/push [sound wave] created by one single buzz [resonance] of your lips travels down the tube [air column]. [When you play the note A at 440 Hz your lips vibrate 440 times a second.] It then bounces back when it hits the ‘wall’ of the outside world air pressure AT THE BELL. The air pressure inside the tube is less than outside so the waves bounce back.
...
From all this, we see that the ‘bouncing back’ from the ‘wall’ at the bell is absolutely fundamental to each note. A bell will make the lower resonances respond better. This is why the fundamental harmonic is easier to play when the bell is larger. This is because the bell graduates the change to the outside air pressure and allows the sound waves to, conceptually, ‘slow down’ and bounce back with less interference.
...
So, yes, big bells make for easier fundamentals and a broader sound. However, they militate powerfully against a focussed clarity, immediacy of response, a ringing sound higher up and can produce an over-bearing, booming, un-brass-like sound when played as loud as possible.

... in short, it's why the tuba isn't a big trombone.

For a much more technical but very readable investigation, see "Rick Denney"'s The Tuba Sound article, wherein he looks at audio spectrum data from a wide bell York Master and a more stovepipe Miraphone.

[Matt G]

The spectra are interesting, but limited in scope. Rick points to the test being improved in terms of dynamics. I'd appreciate a sampling of players with their mouth piece of choice plus. Also be interesting to fiddle it the mouthpiece as a variable as well.

I was thinking the acoustic pressure inside the horn is really all that matters. Ambient should be similar otherwise. The change in surface area of the wavefront becomes too rapid at some point in the bell and it just wants to go home; that's the impedance drop. Well actually, it's a principle of least action deal, but that calculus is messy.

There's likely something going on with the idea that the tuba as a waveguide supports a higher number of (horizontal) modes depending on bell/throat dimensions. The wider the throat, the larger the number of modes supported, which would show in the spectrum as higher overtones, like Rick's experiment. It's somewhat contradictory in thought to the "bigger throat, more fundamental" concept, but acoustically and mathematically, it makes perfect sense.

[Donn]

There's likely something going on with the idea that the tuba as a waveguide supports a higher number of (horizontal) modes depending on bell/throat dimensions. The wider the throat, the larger the number of modes supported, which would show in the spectrum as higher overtones, like Rick's experiment. It's somewhat contradictory in thought to the "bigger throat, more fundamental" concept, but acoustically and mathematically, it makes perfect sense.

You lost me on (horizontal) modes, but he does talk about the perceptual issues around "more fundamental" in this context:

The principle overtones in the Miraphone sound are two or three dB lower than the York. But the high overtones, starting with the 8th and going up from there, are much lower than the York. On the face of it, we would assume this meant the Miraphone had a darker sound than the York. Yet, the York's sound is deeper to my ear and those who have heard both instruments. By deeper I mean that it seems to have more depth or bottom to it.

I would therefore like to define darker as having less prominent higher overtones, and deeper as having an overtone series that reads to the ear and brain as a deeper note. And now, at last, I understand why some orchestral players love the big American-style instruments. They praise their depth and color, and that color, with its more even range of overtones, is interpreted by the listener as deeper. And why others praise the dark, focused sound of the German-style instruments, which less emphasis on the overtones, and more of the sound coming from the core frequencies--those closer to the fundamental.

Unfortunately, while that seems to be a fairly central point to the whole discussion, I don't see where he really nails down how its overtone series makes the York Master sound "deeper." He focuses solely on the higher overtones, and you could infer that he sees that as the deep factor, but he doesn't really explain how that could make sense - and as I read the figures, its 2nd partial is significantly stronger than the Miraphone, which would be such an obvious explanation that it isn't very interesting. Where did the big 2nd partial come from - is it, too, a function of the big bell? Maybe along with the more dynamic levels, players and mouthpieces, we need a couple more tubas. I think it's fair to say the large tubas of the world don't all sound the same.

[Matt G]

You lost me on (horizontal) modes...

Just to clarify: the tuba bendy parts instill particle motion that isn't uniform; not only is the air column vibrating longitudinally down the axis of the bugle, it's got some transverse motion as well. That's what I'm labeling as a horizontal mode. I think those are helping support the upper harmonic structure as well.

The "deeper" timbre is likely a misnomer. It's got a lot more presence of upper harmonics.

I think the same issue would show up on other instruments as well. Bass trombones that "sound bright" are probably lacking upper harmonic levels as well. They, too, usually have smaller throats in the bell.

[2ba4t]

Just caught up on Tubenet. Well, I did write, “I would be grateful to be (yet again) put right.”

And boy, did I get put. Many thanks.

It certainly would have been clearer to have entitled the post ‘Fake news: Are we too suggestible?’ and added some link material between the paragraphs. Sorry to have again raised so many hackles, especially those of the pachyderm. And I one hundred percent agree with:

“ by the elephant » Fri Jul 12, 2019 10:15 am
I just hate careless writing. I hate intellectual laziness in general. I guess the partial anonymity of the Internet still affects some people so that they don't care about details. That says a lot about them as people, though.”

Sorry.

The idea was that:
1) Trombone bell material is a proven deception (– yes, unless you want a particular bell just for its colour.)
2) This suggestibility idea applies to tuba size and bell size – with respect ONLY to the effect in tutti fff passages, out in the auditorium or at the recording mixing desk.
3) Obviously huge tubas sound different from tiny ones and low tubas are much more effective down the bottom, high ones less hooty at fff up the top.

Still the total effect on the general orchestral colour may IMHO not relate to size or pitch alone. But, following this idea, a clever player can use tactics – not brute size or volume. This is what the best guys I know did and even I also tried this.

Bloke kindly posted on this and mentioned recording bells. I had the same experience of hearing an entirely different sound. Obviously practising right up against a smooth hard wall helps at first. But because the sound (standing) wave actually completes itself only about one to two feet beyond the bell, before the bounce back, I left a space of about the size of an inverted tuba mute. But, thanks, bloke, I loved ‘rhinovirus’. Please explain PWWP. What is not PWWP? I am now deeply concerned about my trousers - as we call them here.

Kpen mentioned other suggestions for ‘tactics’. That would be a wonderful separate thread IMHO. I will now again anger the world by doing just that – unless I have been locked out of Tubenet for not yet grasping its culture.

I note that I was dubbed a ‘lurker’ but now am a ‘bugler’. If the answer can be legally printed, what do these epithets mean? In England, ‘lurker’ would be deemed libellous probably – unless proven to be true, in the public interest, expressed as a personal opinion etc. But I just love it: I have always crept around in a mask leaping out at people late at night.

[Donn]

If the answer can be legally printed, what do these epithets mean?

I as I'm sure you've guessed, they're assigned by how many times you've posted. Common feature of bulletin boards like this. Here the grades are presented as a number of valves, from 0 (bugler) to 6. "Lurker" is a common term for those who read but don't post, and has been used enough in that sense that it even appears in my dictionary.

[2ba4t]

I am slightly confused when reading the following two bloke posts together:

ONE

Re: Tuba tactics and false news.
Post by bloke » Fri Jul 12, 2019 9:47 am
I - for one - am SICK and TIRED of all the nose-pickin' (now: not just computer viruses, but rhinovirus as well) that goes on here, along with other lack of decorum - which, among other things, includes PWWP (posting without wearing pants).

TWO
the beautiful and decorous artistic portrait accompanying - "by bloke » Sun Jul 14, 2019 10:17 am ... If the thong fits ...".

I would have also asked that the latter does not explain PWWP because it does not show whether the young gentleman depicted is or is not wearing said item of apparel unmentionable in polite British society - but I shall not do so as this would probably invite an avalanche of similar and perhaps too instructive pictures which may get tubenet banned, or make it the most watched site in the ether or put on the dark web. Please, I am fully enlightened, so no more pictures (especially as it so resembles me).

Hey, guys, subject for new post???? - "Do all tuba players look like that?" Or perhaps "Is it justified to ban all skinny tuba players?" or, returning to original post - " Should your bell size be more than half your waist size?"