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Friends, Just picked up a Conn 14J on eBay. Charming horn, but it appears to have received a lead pipe swap at some point in its life. The picture from the eBay ad shows the "double lyre" setup that suggests the prior swap-out. Best I can tell the lead pipe is not an original or NOS part, because the horn plays about a half tone flat will all of the slides pushed in and an appropriate sized mouthpiece in place. I've got a Bach Mt Vernon 22 that fits the receiver fine and sounds great if I don't mind being a half tone flat! It's an agile little horn and is a lot of fun to play.

What approach should I use to get the tuning back on track? Am I better off cutting the main tuning slide or finding a different (shorter) lead pipe?

Thanks for your kind assistance!

I don't think shortening the lead pipe will get you there if you are a half-step flat. It looks to me as though the main slide is waaaay too long.

BTW... a half-step would be about the length of your 2nd slide circuit if you want an idea of how much tubing would have to be removed.

BTW.... the 14J was a VERY short run but shares some parts with the 12J.

Here's the receiver



Lead pipe solder joint... this joint is moist as I play



and here's the lead pipe



"Crysteel" valves look OK to me.

Thanks to all for your kind assistance!

I dropped the horn off for a diagnostic eval today... results back soon. Initial look by the tech raised concerns. Here I was bragging up my beautiful pristine valves and he noted that they'd likely been re-plated at some point, and raised the additional concern that the lack of some scoring usually means poor compression. He accentuated this by demonstrating some "wiggle" of the valve within the valve casing... not good. I'll try not to worry TOO far ahead of the process, but if the valves are shot via the valve casings, I'll be facing a resurrection challenge. Given the overall cosmetic condition of the horn I'm not above a Frankentuba approach. Bore for this horn is 0.725... any chance that I could find a compatible 4-valve/tubing set that I could use to replace the existing hardware?

Will pistons 1 and 3 interchange? I have a King baritone that I swapped which resulted in a better average fit due to more wear in valve 1.

Pat S wrote:I dropped the horn off for a diagnostic eval today... results back soon. Initial look by the tech raised concerns. Here I was bragging up my beautiful pristine valves and he noted that they'd likely been re-plated at some point, and raised the additional concern that the lack of some scoring usually means poor compression. He accentuated this by demonstrating some "wiggle" of the valve within the valve casing... not good. I'll try not to worry TOO far ahead of the process, but if the valves are shot via the valve casings, I'll be facing a resurrection challenge. Given the overall cosmetic condition of the horn I'm not above a Frankentuba approach. Bore for this horn is 0.725... any chance that I could find a compatible 4-valve/tubing set that I could use to replace the existing hardware?

Building a Frankentuba is unnecessary. If it really needs to be done, the pistons would be plated larger, the casings honed straight and then the pistons would be fitted to the bores of the casings. A pretty standard approach. Not every shop is equipped to do such work but it can be done. The valve set needs to be removed to do this work but the cost of substituting a different valve set might be more expensive than having the present set refurbished.

Thanks for the insight... very helpful. Glad to near that there is a solution even if the valve casings are shot. I'll certainly try Hetman's thicker oil first. Tech thinks that the "new" lead pipe is simply too long and is going to cut it down to size before doing anything else (like cutting the main slide). He's also going to leak test the horn and check tolerances/blow-by on the valves. More updates to follow.

I have the same horn, with the same replacement lead pipe. When I got the horn, it had the original leadpipe, which had been mashed and repaired too many times. It had a small shank receiver, and even with a small shank MP, it played very flat. If you used a large shank euph or base bone MP, it would almost play up to pitch, but of course it sounded like a bad euphonium, not a tuba. I had the leadpipe replaced. The new one looks just like yours, and is an American shank. It still plays flat - probably a bit more so than before. With a Wick 5L, I have to set the tuner to A435 to center the needle.

I'm interested in your story, as I'm going to have to do something, too. I'm hesitant to shorten the leadpipe, as I will then have one eye mashed into the bell. I know mine needs new felts and corks, and heavier old. Needs to be checked for leaks, too. None are obvious. I'm going to do that before having it hacked.

Your main tuning slide is the same length as mine.

BTW: I've tried a bunch of MPs, and the Wick 5L works best for me. A PT-64s has a little better bottom, but the 5L works best through the whole range. We'll see if any of this changes after I get it worked on.

Keep us posted!

I'm thinking there might be a very good reason why the 14J was a very short production run.

I've never had an opportunity to 'work one of these horns over' and am curious.... how are the lengths of the valve circuits? Are they consistently flat in relation to the open bugle? If they are... simply cutting the open bugle (leadpipe and main slide) of the horn is just a portion of the job.

It's an agile, fun horn, so I don't mind having it tweaked to make it playable. That tweaking will likely involve smart repair folks doing public math to get the tuning as close to "OK" as possible. Since I'm not restoring it to sell, I have more patience... I'm more interested in joy than profit, and I have a contrabass tuba that's keeping my plenty busy right now. Will keep all informed as things go along. One TubeNet friend sent me a box of 14J parts. The lead pipe he sent my way is an original lead pipe, which measures 12 1/4 inches to my tape. I didn't measure the one on my horn before passing it along to the experts. More info to follow!

Update: Non-original lead pipe quite the problem. Looks like the prior repair tech used a pipe of a larger diameter and just "crimped" the end and soldered, causing a leak. Pipe also quite a bit too long. Also leaks in the first valve knuckle, requiring a patch, and a leak at the second valve knuckle joint, soldered and repaired. After this work the pressure checks are now fine. I brought along my mangled original lead pipe, and sure enough even the shortened lead pipe is too long. We're going to look for a replacement, rather than tackling the job of cutting the main slide... update to follow. There'd be no way to take enough length out of the nonstandard lead pipe to do the work and still have a playable mouthpiece position. Tolerances at the valve casings are "a bit broad", but there's hope that a thicker oil will suffice... won't know until the other problems are fixed. Quite a can of worms, but I'm not ready to throw in the towel just yet.