In the past (as quite a few of my betters - ie. people who play better than I do), I worked out embouchure "shifts", because - with "dynamic" tuba playing, the teeth range from being apart over a quarter inch (the loudest and the lowest) to closed down, as if playing a trumpet. Shifts allow the skin (and the muscle under the skin) to not be pinned down in position to play in one range with the player looking for logistical spots in the music to "shift" to re-centering the mouthpiece (typically, a new spot in the indention below the lips and above the chin.
My narrow rim (as a result of experimenting with ideas - I'm no engineer nor any type of scientist...just someone who attempts to think) and the contour of it (as an XY chromosomes person) offers even more of its benefits when I shave around my mouth before I play (whether it's noon-shadow, 3 o'clock shadow, 5 o'clock shadow, or 7 o'clock concert shadow) which allows this particular NOT-wide and NOT-sharp-turned profile of rim to SLIDE across that indention whereby I affect GRADUAL (rather than sudden) shifts from one range to the next. Shaving also slows down micro-scratching of (very easy to scratch) plated brass rims, which I why I tend to prefer stainless steel rims (which are much more scratch-resistant, so they - as they remain smoother - slide all the easier).
- trumpet mouthpiece rims are narrow
- trombone rims are mostly narrower than most tuba mouthpiece rims, so..
...as tuba rims involve so much more metal against the face regardless - why do we put even MORE metal against our faces with wide rims?
Wide rims are no more of a "cushion" to our faces than "sousaphone pads" add actual cushioning when carrying a sousaphone (as all the weight of the sousaphone is still concentrated in the same spot, yet we've added even MORE weight by installing a pad).
OK...The immediately-above is a very imperfect analogy, but still somewhat valid.
I also don't buy into the idea of dished rims on brass mouthpieces (a very old idea, abandoned, yet brought back several years ago). Again, that's something that creates even more contact area and less opportunity to reposition the mouthpiece on the skin-over-muscle as (particularly with tuba) we affect these epic opening and closing of out teeth spacing (unlike trumpet and only slightly required when playing tenor/baritone brass) to play across the range of the instrument...and the more gymnastic the passages we are individually required to play, the more noticeable a wide rim (or a sharp interior turn rim) can become a hindrance as we epically open and close our jaws (teeth).
At first, some who try this rim profile tell me that (regardless of donut size) they feel uncomfortable, because the mouthpiece feels to "big".
I suspect that what they are feeling is the LACK of all of that contact, and what they are feeling (rather than "big") is "next to nothing" (ie. far less contact, vs. the rims to which they are accustomed).
I don't use the same very rim for all of the tuba-family instruments I play, but I DO use the same rim PROFILE (rim width and curvature) for all of them, whereby there are three different "donut" sizes" (which translate to "cup openings") that I personally choose to use with different tubas and with different cup shapes and throat sizes. The consistency in rim PROFILE is for all the reasons expressed in the above screed.
bloke "not only does the mass of a mouthpiece have no discernible effect on the way a brass instrument mouthpiece performs (as claimed in another thread - just to irritate y'all
, but - additionally - I suspect that "all that metal up against one's face - at least, with a large percentage of players - might be detrimental. I can personally barely play most wide-rimmed mouthpieces (not just because they don't glide nicely across my skin, allowing me to avoid sudden shifts, but) because most of those - with all of that unnecessary rim width - jam themselves up against the bottom of my nasal septum - as the space between my particular nose and lips isn't very tall (which is part of why I'm so butt-ugly)...and yeah - with my threaded steel rims, I still offer a bunch of profiles to which many players are already accustomed, and Dave offers several others as well...but - at least, on my one-piece silver-plated brass "new" mouthpieces - I'm going to only offer the rim profile described above."
