Looking at a variety, they all seem to have a certain amount of internal cupping and funnelling.
For example which is the PT-48? I am having trouble deciding



Neptune wrote: For example which is the PT-48? I am having trouble deciding
So that's what they say. As you noticed, though, it's relative. Especially with deeper mouthpieces, it seems to me, a deep mouthpiece with a distinctly funnel shape starting from the rim might be uncommon. The word "funnel" and the name "Helleberg" are widely used, but of a dozen or so ostensibly funnel shaped mouthpieces I have, three really are, and they're all made by Conn.Custom Music wrote: PT-48
CUP CHARACTERISTICS: 33.5 mm. diameter - Deep - Funnel-shaped cup - Rounded at bottom
RIM CHARACTERISTICS: Width 8 mm. - Rounded inner and outer edges
THROAT BORE: 8.5 mm.
Model PT-48 is a funnel-shaped mouthpiece which produces a full orchestral sound. It is recommended for players with strong embouchures and is designed especially for use with larger bore CC and BBb tubas.



Can you say more about it? I've never seen one, in person, and of course a picture of the outside of a mouthpiece doesn't give us much to go on.SplatterTone wrote:There is no doubt that this is a funnel.
http://tinyurl.com/ynvb9x

I have a green one. It's not as bad as it looks. I don't think it will inspire anyone to new heights of greatness, but it plays OK. I measure internal diameter at about 32.5mm give or take a bit. I does demonstrate how basic a mouthpiece can be and still work. It's just a plain, straight funnel with a rim.Can you say more about it?

What I see is that the MF3 and the MF4 are very similar at the shank end. The difference (it seems to me) is that the MF4 has a nearly-cylindrical section added.The Jackson wrote:Gaze here at cutaways of some Mike Finn mouthpieces.
You can clearly see the difference between the bowl cups of the MF 2 and 4 and the funnel of the MF 3.
(Thanks to Mr. Finn for these cutaways and making awesome mouthpieces)


Exactly, and if I had a cut-away of my MF3B you would clearly see this compared to the original MF3.Neptune wrote: Presumably cup would provide a higher volume to diameter ratio?
Only if my photo is used to show something other than what it was originally intended for.This leads to the conclusion that "cup" = "shallow" and "funnel" = "deep".


I love these cut-out photos! But I'm not going to saw my Conn 3 in half, just to show a shallow funnel.Mike Finn wrote: For my purposes, a bowl-shaped cup has a sharper, more defined entry to the throat, providing a little bit of resistance to the airflow, and possibly making it easier to control or "steer" the tuba. A funnel, like my original MF3 (or the Helleberg after which it is patterned) will have a smoother entry to the throat providing a little less resistance.
Why would that be? It seems to me that you'll get all sorts of reflections and cancellations within the cup, and that the interior shape will affect which frequencies are reflected and cancelled and to what degree. The cancellations might affect only the highest frequencies, but that is where the mouthpieces differ most in sound, it seems to me.sloan wrote:In my opinion, the only thing that affects the *sound* is the volume of the cup.

Remind me: what is the range of WAVELENGTHS that you consider relevant, and what are the interior dimensions of a tuba mouthpiece?Rick Denney wrote:Why would that be? It seems to me that you'll get all sorts of reflections and cancellations within the cup, and that the interior shape will affect which frequencies are reflected and cancelled and to what degree. The cancellations might affect only the highest frequencies, but that is where the mouthpieces differ most in sound, it seems to me.sloan wrote:In my opinion, the only thing that affects the *sound* is the volume of the cup.
Don't know of a controlled study, but the differences between some mouthpieces and others are unsubtle enough and consistent enough among different performers to support some conclusions based only on anecdotal and empirical data. They won't explain why, but they will demonstrate what.sloan wrote:Remind me: what is the range of WAVELENGTHS that you consider relevant, and what are the interior dimensions of a tuba mouthpiece?
In my opinion, the range of existing mouthpieces is far too limited and the number of significant differences between any two mouthpieces is far too large to be able to confidently put forth any valid model of bowl vs funnel.
Is anyone aware of published data reporting anything like a controlled study?


Or it wouldn't, since we don't know how to match the throat and back bore. Should they be the same size, or do those parameters vary with volume?Rick Denney wrote: I agree, to a point, with your second statement above, but it contradicts your earlier statement that I disagreed with, namely that only the volume affects the sound. Is there a small funnel that sounds like a stereotypical funnel compared to a larger bowl that sounds like a stereotypical bowl? That would test your statement, it seems to me.


Why is it important to differentiate!?Neptune wrote:How can one tell if a mouthpiece is cup or funnel.
Looking at a variety, they all seem to have a certain amount of internal cupping and funnelling.
For example which is the PT-48? I am having trouble deciding

In extremis, you could pair a Conn Helleberg 5E (euphonium) with a PT-88 ... might be interesting.Rick Denney wrote:... Is there a small funnel that sounds like a stereotypical funnel compared to a larger bowl that sounds like a stereotypical bowl?
Indeed it would!MaryAnn wrote:It would be fun if someone out there with the proper equipment, mindset, and free time, would do a "continuum study" of various mouthpiece parameters. That is, define a set of parameters and vary them one by one over a reasonable range of differences, and log the results. It would be cool.
