TromboneChat

On my large bore (Yamaha 548G) I play a 51C4 - which I realize as I type this about 10 years after my parents bought it for me, that I've been using that mouthpiece mostly because it came with the horn, purchased used.
However, it's proven to be a fantastic mouthpiece for me, pure luck that it's such a good fit. I've experimented with others like a 6.5AL, 5G and 4G on this horn, couldn't really capture the zippiness nor get the same flexibility or feel as the 51C4. I also really like the flatter rim, it seems to produce less of a focused pressure point on the lips for me than more round-rimmed mouthpieces like the 6.5 or what I've experienced with #G-mouthpieces.


All that is to say: right now I've got a Yamaha 48 on my small bore (Yamaha 354), and I'm not completely satisfied - particularly with the flexibility which I feel is a result of a slightly-too-small rim (I'm practicing LOADS on this of course) and I could go for a little darker/richer sound. Would matching mouthpieces (rim sizes) actually be a good choice? Could anyone recommend some other brands/models that have similar characteristics? It seems like the 51C4 is a shallower version of the 51 - correct me if I'm wrong. Would it be weird using a deeper mouthpiece on a small horn?

I usually use this horn for lead/small combo playing. I've experimented a lot with mouthpieces on my small bore (Several 12Cs, 6.5AL, Remington, Ya 47, Yam 48, among others), but almost not at all on the large bore - I have the 51C4, and a Kelly 1.5G for psuedo bass playing.
The big thing keeping me from making a move is the cost of buying one mouthpiece these days just to try it for a few months. When I was in highschool, you could buy Bach or Yamaha mouthpiece for $40.. now they're about $70+!

First, the Yamaha 51 is quite different from the Schilke 51 - I think it's not quite as deep and has a smaller throat.

Second, yes, the Schilke 51C4 is shallower than the 51, but I believe it also has a flatter rim profile, which you seem to like.

Third, there is also a 51B which is shallower still (and also a 50C4, but I've never seen one of those so I would guess they are hard to find).

Schilke gives good information here: https://www.schilkemusic.com/products/m ... ard-series

FWIW, a friend I used to play with occasionally played a Yamaha 51 on his large bore and a Schilke 51B on his small bore.

Oh, you're talking about a Yamaha 51C4.

As I suggested, I don't think the Yamaha mouthpieces are exact copies of the Schilkes.

https://usa.yamaha.com/products/musical ... oduct-tabs

They also make a 51B and a small shank 51C4

“When I was in highschool, you could buy Bach or Yamaha mouthpiece for $40.. now they're about $70+!”

Wait until he checks out the costs of a Greg Black or an Elliott etc.

Yamaha mpcs are still pretty inexpensive. ~ $50.

As Gabe Rice has pointed out, Yamaha mouthpieces may have similar model numbers to s Schilkes, but they are NOT the same. Yamahas are typically a bit smaller than Schilkes (Rim and Cup) with different rim profiles.
I've never been comfortable with a 51B from either company; they are somehow just weird for me.
I like the Schilke 51C4 for large bore.
I'd be interested to try a 50C4 but they are rare.
You could eventually capitulate (as I have partially done) and switch to Doug Elliott pieces where you can get the ideal Rim I.D. and Cup depth (as well as Backbore) - but it.will cost some $ and take some trial & error.
Good luck.