Mouthpiece Taper for old Conn small-bore tenor trombones

[Posaunus]

Mouthpiece Receiver for old Conn small-bore tenor trombones

I recently purchased a Conn trombone on eBay. The seller was uncertain of the model, but said the serial number identified it as from 1937. He thought it was a Conn 6H (which I was seeking) – but noted that it had a 7" diameter bell (not typical of a 6H), and uncertain engraving. He admitted that it had “dents and dings and some wrinkles on the bell flare” but claimed that it was otherwise in decent condition. The starting auction price was low, so I bid on it ... and won it at a very favorable price.

Sure enough, when I received it, the case was shot and the trombone had obviously had a hard life. I brought it to John Sandhagen at The Boneyard for restoration. John not only did a great job refurbishing the trombone, but he identified it as not a 6H but a Conn 30H “Burkle” actually from 1936. This is a tenor trombone, 0.494"/0.507" dual bore, 7" bell. Tapered bore through bell, tuning slide, bell taper, hand slides, and hand slide bow. Designed by “Jake” Burkle at Conn.
https://cderksen.home.xs4all.nl/Conn30H1940image.html

Now fitted with a little better case, this is a nice instrument, though a little unusual, so I’m not sure where I’ll play it after we can start rehearsing again together. (Lead in a big band, chamber ensemble, trombone choir, jazz combo, … ?)

One unusual feature is the mouthpiece receiver. The only mouthpieces I have that fit the receiver are a Conn 3 and a Conn 2. [Fortunately, these mouthpieces play quite nicely in this trombone.] All my other small-shank mouthpieces (Bach, Schilke, Yamaha, Wick, Marcinkiewicz, Doug Elliott) “wobble” when inserted. So apparently this trombone has (or all small-bore Conn trombones of this era have) a different taper in the leadpipe / mouthpiece receiver. I know this was the case for Elkhart-era Conn large-bore tenors, which had a “Remington” taper. I was not aware that this was true of the Conn small-bore tenors.

Is this feature typical of older Conn small-bore tenor trombones, or do I own an outlier?

[BGuttman]

Dunno. I have a Conn 40H from 1930 and my small shank mouthpieces fit fine. Including a Doug Elliott LT 102/E/E2.

Maybe the receiver part of the leadpipe is worn?

[Doug Elliott]

Some old horns, not just Conns, had unusual receivers - or the leadpipe and receiver could be damaged. If it's not damaged, i can make something to fit if you can give me enough details- or you can try my "s" taper which is likely to be about the same as the Conn mouthpieces that fit.

[Nobbi]

Actually I have a Conn 4h from 1940 here at home to test.
My only small shank mouthpiece, a MT Vernon 15C fits perfectly.

You may post an image of your refurbished 30h ... at least I am curious.

[jacobgarchik]

I have 4 20s Conns. I also have 8 or 9 20s and 30s Conn mouthpieces. All the horns fit modern mouthpieces and all the mouthpieces fit modern horns. So not sure what's going on here.

[Posaunus]

Thanks, all, for your replies.

Apparently my 30H from 1936 is indeed an outlier. I can certainly imagine that the leadpipe could have been damaged over its 84-year lifetime. What I don't understand is both my Conn mouthpieces seem to settle in without any wobble!

Is it feasible / reasonable to replace the leadpipe on this trombone? Is it worth it since I have two Conn mouthpieces fit well and play well? (I don't expect I'll be playing this trombone as my daily driver.)

[dukesboneman]

I had a 30H years ago and My Bach 7C fit fine It was a very open playing horn for it`s size

[Doug Elliott]

Compare the way those two Conn mouthpieces fit in another horn.

[Posaunus]

Doug,

I checked the mouthpiece fit into some other small-bore trombones.

Conn - as well as Bach, Schilke, and Doug Elliott - mouthpieces all settle into the Conn trombone receiver so that just about 1.0-1.05 inch is buried. (I think that's the ideal?) At that point, the shanks are in the vicinity of 0.480"-0.490" diameter. (This is true, by the way, of a Conn 6H as well as a Conn 30H.) But on other small-bore trombones, both these Conn mouthpieces (Conn 2 and Conn 3) only sink in ~0.80"-0.85"

[I don't have an ideal mouthpiece measuring system. And unfortunately, all measurements here are approximate. My inexpensive digital caliper is acting up.]

The tip diameters of these varied small shank pieces are obviously different. The Conn mouthpiece tips are about 0.429"-0.434" diameter, whereas all the other small-shank pieces have tip diameters of ~0.421"-0.425"

Summary: the shanks on these older (uncertain age) Conn mouthpieces are indeed different from my other small-shank mouthpieces. The Conn shanks are a bit larger, and have a different taper. They do not settle into other small-bore trombones as far, but are still usable. Non-Conn small-shank mouthpieces wobble in my Conn 30H; my Conn mouthpieces do not. But all the small-shank mouthpieces I've tried, whether Conn or other, settle in to other Conn small-bore trombones just fine, and play perfectly well.

Since the "wobble" I observed only occurs with the Conn 30H trombone, I guess its leadpipe must indeed be damaged or different in some way.

Conclusion:
I like the way both Conn mouthpieces play in all my Conn trombones, so will save them for that use.
For other small-bore trombones, I'll take something suitable out of my mouthpiece drawer – or use the DE setup I've just acquired from John Beatenbough. (Thanks, John and Doug!)

[Doug Elliott]

The receiver in the 30H gets smaller just past the end of the Conn mouthpiece shank. Other mouthpieces hit that smaller place or ledge, and don't seat all the way. It could be wear or expansion from having used those particular mouthpieces over a long time. I can make a shank that will work, if you want.