TubeNet

Bruno Tilz WH-B2.

Give it a try, it's a large mouthpiece, but it can do anything on BBb (at least Walter Hilgers can )

Wim

Try one of the Mike Finn mouthpieces: MF3 or MF3B or MF3H, depending on your bowl and rim style preference. I use these in my 6/4 BBb's with good results in both ends of the range.

lot of good MPs out there....MF 3 series are great, but wider than what you are acclimated to...try the 3H , it s a little edgier and feels "smaller " than its measured size.
Doug Elliot makes great MPs and of course Mr Blokes symphony is perfectly suited to large BBb or CC horns .
Alot of guys in this forum like the Perantucci mouthpieces. The PT 48 seems particularly popular, but again, its wider @ 33 or 33.5mm-

I like the PT88 in my 192 clone.

I presume the PT-90 does not work Kurt? How does it sound with that?

The Bach 18 does have a larger throat than you spec'd, but it doesn't really play any larger.

I have found for mouthpiece recommendations that Matt Walters or Roger Lewis can most often nail what a person needs first time out. I recommend you contact one of them. Caveat: you have to be painfully honest about your playing: what you're reasonably wanting to do, repertoire, strengths, and most importantly, weaknesses.

Everybody else will give you their favorites, including me, which may not fit your breath support, embouchure, technique and repertoire.

To get an idea of what is out there in your preferred cup diameter, here's a great chart:
http://www.allbrassradio.com/tubampccharts.htm" target="_blank" target="_blank

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