I have been experimenting with various small shank mouthpieces on my Besson 2056-2 4V compensating baritone.
The bundled Alliance 6 did not work for me at all. Too dark and muddy. That MP found a good home in Doug Ruby's collection. Then I acquired a Wick SM6B, which was slightly better than the Alliance 6, but still not right.
I was looking for something significantly brighter. My preferred genre is traditional New Orleans brass band music (VERY different from the British brass bands!). The Wick SM9B has a V cup, and was much closer to my desired tone.
Also tested were several custom "tweaked jazz trombone" 6.5AL variants: the Loud LM52, G&W Harry Watters, and Monette TS6. All three of these MPs were closer to the desired tonal response. However, low end response and overall slotting suffered with all of the 6.5AL variants. My rusty embouchure is also part of the problem. I will be posting these three MPs in the "For Sale" section soon.
One thing that bothered me about the Wick MPs and the 6.5AL variants was the amount of main tuning slide pull. All required 1.125" to 1.25" of slide pull, which is way too much in my opinion. Not enough pull to blow out the tuning slide, but too close for comfort.
I dug into my old MP box and pulled out a small shank Shilke 51D that had been used with my Conn 24-I. Slide pull with the 51D was only about .50". It was almost as if the 51D should have been the original bundled MP!
Shank lengths were also measured. The Shilke 51D shank is about .25" longer than the Wicks and 6.5AL variants. The difference in slide pull appears to be a combination of the longer shank and deeper cup on the 51D.
I am currently practicing exclusively with the 51D as I slowly build up my chops. The 51D is still too dark for my taste, but overall seems much better acoustically matched to the horn. Slotting is noticeably better, especially on my lip-slur exercises. My next step is to test a Shilke 51C4 to brighten the tone just a bit. Any other suggestions?
Also, does anybody have an explanation as to why the Shilke has a longer shank than the other small shank MPs?