JK 6B mouthpiece

[modelerdc]

In an earlier thread I asked if anyone had information about how the depths of JK mouthpieces compared to some of the better known mouthpieces in the US. The only real comparison I could find was that some of the JK models were listed on the mouthpiece comparison charts on Doug Elliott's site. Unlike most mouthpiece comparison charts Elliott's compares depth as well as rim diameter.
This was important as I had come across a JK 6D with bass trombone shank for use on a contra bass trombone. I had been playing the dreaded 24AW on tuba and the 6D had a nice rim size for me. So I wanted to get a JK mouthpiece with the same rim but with a cup more fitting for my Boosey 3+1 E flat tuba. I've also use the Helleberg 7B and the Conn 2. After looking at Elliott's charts I decided to order a JK 6B. Dillons had it in stock and in a few days I had it. The B cup is similar to the cup on the Conn 7B, just a little shallower (not much) perhaps a little more bowl shaped, and a larger throat. My 24AW measures 31.25mm, the JK 31.5, and the Helleberg about 31.6. But the JK feels a bit larger than the Helleberg, probably because the rim on the Helleberg is so flat. The JK rim is more middle of the road, a little more rounded than the 7B but less so than the Schilke Helleberg. For me the Schilke and the 24AW were comfy, but the 7B promoted accuracy better. The JK seems to be a good compromise that does both well.

Other than comfort and accuracy how does it play? it's easy to play with a bit of color to the sound. Helps give the Boosey/Besson some personality rather than just sounding all the same. I can play a bit louder on it although in the lowest tessitura it will bark just a bit, no surprising as it is shallower than the 24AW I was using. I believe it may be just the thing for solos, brass quintet and such. For large ensemble I've gone ahead and ordered the next deeper size, the 6A. It's not in stock as yet so we'll have to wait and see.
With the JK line I may have found a line of affordable mouthpieces that are well made and available in a good range of rim sizes with a very useful range of cup depths for those rims, all as stock items.

[Donn]

Interesting!

The B cup is similar to the cup on the Conn 7B, just a little shallower (not much) perhaps a little more bowl shaped

I think the same could be said of every other current production tuba mouthpiece, though. At least, my 7B is more funnel shaped than anything else I've seen.

[Søren]

When I was a teenager and bought my first tuba (Conn 14K sousa), my teacher (trombone guy) brought a few tuba mouthpieces for my to try, and the JK 6B was the best one. I then used that mouthpiece for everything the next 6-8 years on all kinds of tubas and music styles. I eventually found some mouthpieces that I like slightly better (different helleberg type mouthpieces), but that JK 6B never held me back in any way and is still the one I go back to when everything else fails....

I think that you are correct in that it is slightly more bowl-shaped than a standard Conn 7B, and the edge is certainly more rounded than a Conn 7B.

Good luck with your purchase!