pjv wrote:Doesn't putting a bit in between your mpc and the leadpipe mess up the fragile mpc+horn relationship?
In the case of Martin, the "bits" are part of the leadpipe design. The earlier, original Martin bits are more like an "articulated leadpipe" as the pieces fit together with very close tolerances and are held in the desired position with set screws......similar to present-day Bundy bits.
The articulating part of the leadpipe very conveniently accomodates a variety of holding positions, player heights, or use with a stand. A friend played my Martin last night. First thing he did was adjust the bits a few degrees so the mouthpiece met his face the way he preferred. It's "too bad" more tubas aren't designed that way!
From what I've read, the Conn 2xJ series figured the use of one bit as standard setup.
I once owned a Miraphone 191 that played quite sharp with a mouthpiece I liked. Using one Conn sousaphone bit on it gave me:
1) more comfortable holding options,
2) focused the sound in a desireable way, and
3) played in tune without having the main slide pulled so far out.