Conn 5J/12J/15J/3J bell trim and/or swap?

[joh_tuba]

These horns comes with a VERY pronounced 18" pancake to the bell even though the throat and everything else about them is *notably* small.

Has anyone out there trimmed these bells down to 16" or 14" and can comment on the result? Just looking at the one in front of me, it could easily be trimmed to 14" and would still have a perfectly reasonable looking flair and barely shorten the length of the instrument.

Are there other bells that mate up reasonably with the bottom bow of these horns and offer a 'punchier' more focused projection?

Thanks bunches!

Here's a picture from Horn-U-Copia to help folks visualize the situation:

[joh_tuba]

Follow up:

According to Bloke in this post: viewtopic.php?f=2&t=33942&p=299912&#p307523

It was common in the 1970s to swap the Olds 0-99(16" bell and probably the same as the Conn 4J which is VERY similar in shape and taper to the Conn 5J) onto a Miraphone 184.

Based on that nugget.. was it ever common to swap a Miraphone 184 bell onto a Conn 5J or similar? Or was this a one direction project?

[TheGoyWonder]

for a punchier sound a shallower/more bowled mouthpiece would be the thing...but these tubas need a decent funnel to extract much quality sound from them. The 16" olds is less likely to blat than the 18" conn, but who knows if the bell flare diameter has anything to do with that.

[Tubajug]

I put a 184 bell on a Bach 869 (same tuba as the Olds O99, etc) and it was really barky. I swapped it for a bell that Dan Schultz made for me from a Conn stack and a Blessing flare. I believe it was 15" across. I liked that one a lot. It had some punch for when I used it on polka gigs, but not nearly as barky as the 184 bell.

I found the thread where I posted about it:

Bach bell swap

[Art Hovey]

What you are looking for is called an 11J. They are not common, but they do exist. Mine plays very nicely.