Rehabbing a Conn 20J

[royjohn]

Last Sunday I bought the Conn 20J offered for sale and pictured here:
viewtopic.php?f=4&t=57217&p=484940&hilit=20j#p484940

This horn is #294xxx, from 1934, the first year of production for the 20J. It has the "Lady Face" on the bell rather than the Naked Lady. As you may be able to see in the picture , the lacquer is mostly shot (about 50%, with lots of scratches), but there aren't many dents. The valves seem to be in pretty good shape. All the slides pull and there are new felts and corks on the valves.

I got a tuning bit and the horn plays pretty well. There is some flatting on the 3rd partial. I have read about 100 pages of threads here on this instrument. I'll get out a mirror and see how well lined up the valves are. The leadpipe is somewhat flattened from the receiver end for about six inches. There are also some small dents in all of the knuckles coming out of the valves. Other than those, there are no dents in the slides and there are few dents in the bell, the big bows or elsewhere.

I figure the things to do are to make sure the valves line up, and then have the leadpipe replaced with a new one from Allied and get the reachable dents taken out of the knuckles near the valves. Possibly this will help the intonation of the 3rd partial.

Other than lining up the valves, repairing or replacing the leadpipe and repairing the dents in the knuckles, I can't see a lot that has to be done. I'm considering stripping the lacquer and polishing up the horn in raw brass, but one poster said taking the lacquer off a 20J ruins its sound.

Interested in any comments about this plan. I'm enjoying the sound of this BAT and finding it pretty easy to play. It appears to be pretty easy to play it softly, so maybe it is one of the good ones.

[royjohn]

I forgot to add that I'll clean the whole horn out well . . .

[Lew]

If you read all the threads on this instrument then you should have read how the third partial is almost always flat on these. It appears to have been a design decision. I have owned 4 of these, including 3 and 4 valve, side action and upright and recording bells. The third partial was flat to a certain extent on all of them. The side action horn was the one that was most in tune, and it wasn't so bad on any of them as to make them unplayable. It sounds like you are on the right track regarding repairs and, based on the ad, that you paid a reasonable price, but don't expect any of it to have much impact on the third partial.

[royjohn]

Hi Lew,

Thanks for the input. If the horn remains where it is on the third partial, I think I can live with it. Certainly it's true that most people experience a flat 3rd partial on these horns.

I read an interesting post by Lee Stofer on these. He says that they will play in tune if three conditions are met:
1. Valves have to be very carefully aligned.
2. The leadpipe and valve slides have to be dent free.
3. The horn must be played with one tuning bit.

It's because of Lee's post that I'm going to make sure to get the leadpipe replaced and the dents which might influence intonation taken out. Then we'll see if it will play any more in tune. When it comes back from rehab, I'll post here on how it plays.

[Lew]

I know Lee said that, and he is a much better player than I will ever be, besides being a great instrument technician, so I value his opinion. However, that has not been my experience. I always used a single tuning bit, had well aligned valves and dent free slides, and still had a flat third partial. I even had one that had previously only had one private owner who bought it in 1934 and it came with the original bit. Even so, as I said, the partial wasn't so flat that it wasn't manageable by someone who is aware of their intonation (unlike so many other amateur tubists, or is it tubaists I have run into).

[Tabor]

I say go for it.



http://s1213.photobucket.com/user/miraf ... eshow/tuba

[GC]

Most folks who play 20J's (and the rest of the 2XJ family) commonly play that F 1-3 (or 4 if available). It just comes with the territory.

[Heavy_Metal]

I say go for it.

http://s1213.photobucket.com/user/miraf ... eshow/tuba

+1

[royjohn]

Thanks for the interesting comments. Playing the F with 1-3 doesn't seem a great price to pay for getting the glorious BAT sound for under four figures (which means less than $999, for the folks who didn't get this terminology last time). If most folks with a 20J have a flat F, that makes you think that maybe fixing the horn won't fix the F, so I'll just have to see and report back.

[GC]

Keeping the leadpipe and valve tubing dent free will make a huge difference in the response of the horn because you'll have less intonation problem with the other open tones, too. The D in the staff can be a particular problem.

And never forget that there are badly flat F's and slightly flat F's. You know which one is better.

[royjohn]

Thought I would resurrect this thread and tell what happened. After considering shipping this monster for repairs, I ended up using my local tech at Rush's Music. He asked all the right questions and wanted to realign the valves and clean the horn in addition to working on the leadpipe, which was the right way to go about it. He was able to get the dents out of the leadpipe and take some of the other dents out of the slides and bottom bow. For $150 I got back a horn that looked considerably better than before and a leadpipe that looked nearly new.

Playing the horn before repair, the problem F at the bottom of the staff was over 20 cents flat and was almost impossible to lip into tune with certainty. After repair I tried six different mouthpieces and that F was still about as flat as before. The rest of the horn seemed to play more in tune, but the F, no. I even tried chamfering the leading edge of a few of the slides and that may have helped a little or it may have been my imagination.

I was beginning to think about trading this monster for something with better tuning when I tried it with no tuning bit. Without the tuning bit I have to pull the main slide to get in tune and I pulled the first and third slides to the witness marks which this tuba has for A=440, about 3/8 to 1/2 inch each. Presto! The problem F ended up slightly flat, maybe 5 to 10 cents, and easily lippable. I ended up with the first and third slides about half as far out as the witness marks indicated and pulled the second valve slide, too, for notes using that were s/what sharp. All that done, the tuba seems do-able, intonation-wise. I'm pretty relieved.

I don't understand why this 20j would play best this way, when the received wisdom is to play it with one tuning bit. I have the required single 20J/20K tuning bit, but the horn just doesn't play right with it. I tried changing the gap, too, with the paper trick, but that didn't work either. Could it be that the part about the tuning bit applies to the later horns, but not to my 1934 model with the screwy pigtail on the third valve slide?

I guess if the horn plays right, it doesn't make any difference how or why, but it's puzzling. The Kellyberg I have seems to work a little better, intonation-wise, than other mpcs, so I'm thinking about auditioning one of the Conn Hellebergs, too, to see if that works even better.

Any comments are welcome. Thanks to Jim of Rush's for his very nice work and one week turnaround time.

[Untersatz]

When I had my 24J it played in perfect tune without using a tuning bit.
I wish I had kept it just for outdoor gigs if nothing else

[b.williams]

FWIW, I play my 20J without the tuning bit.

[Lectron]

I played my 25J both with and without bit.
Intonation was maybe a bit better with, but not by much.

It amazes me thou that people can have large conical horn, cylindrical for that matters,
that play spot on in tune. That is against every law of physics.
Not saying 'can't be played in tune', but that is a different story.

Mine was a fun tuba, but took some time getting used to
Reasons I sold it was being top action and wanting a 5th valve

[Lee Stofer]

I need to clarify a couple of my comments. First, at least the vast majority of these instruments were built with a slightly short leadpipe, and were designed to be played with one tuning bit, which gives the added ability to adjust mouthpiece angle at will. That said, I have over the past few years encountered a number of these instruments that have had the leadpipe replaced with a longer one, so that they play in-tune with no bit. I have also encountered one or two that may have come from the factory with the longer leadpipe.

As for playing in-tune, I am not referring to an instrument that every person on the planet can play spot-on with a tuner on every note, regardless of the environmental conditions, as I do not think that brass instrument exists. I have found that a 2XJ in proper repair plays well-enough in tune throughout it's range to not adversely affect anyone who uses air support and listens. The partial in question is a little flat, but that is the case to differing degrees on a lot of instruments, including York CC's and 5/4 BBb's, and no one questions the usefulness of these instruments. The well-known owner/player of a York 5/4 CC tuba told me that he plays the bottom-line G 1-3. The Conn-Meinl 5/4 CC that I built has a slightly low bottom-line G, and when playing a sustained G at mp volume or less, I use 1-3. It is not an unusual thing. With the big Conns, I think that if you play one enough to really get used to it, particularly if you have played a European instrument that has that partial a little high, any issues will just go away. I have not played one in good repair that I couldn't play the F in-tune, but then I've played them a lot and am probably used to them. The human body is capable of an amazing amount of compensation in many ways, and compensating for the intonational wiles of a given instrument is just one of them. Remember, people used to play ophicleides and serpents (!!!)

I wish you all the best with your first-year 20J. I played a 1934 34J for years, the 4-long-action-valve version of your horn. I personally like the 3rd valve double-wrap at the top, since it brings the slide at the bottom up out of harm's way. The "lady face" you describe is indeed the naked lady engraving for the tuba. The full-body engraving was not used on the tubas and euphoniums, and only rarely on saxophones. The mid '30's engravings tend to be the most beautiful that Conn ever offered.

[royjohn]

Hi Lee,

Thanks for a very interesting and illuminating reply. Now that I'm playing the horn without the tuning bit, I agree with you that getting it to play in tune is a matter of support and a little practice.

The leadpipe on this horn was so beat up before the repair that I thought it had to be original, but with a school horn that old, who knows. Measuring from the middle of the collar where the leadpipe attaches to the stub coming out of the valve casing, around the front (longest part of the curve) of the leadpipe, I get 15". In an old thread, someone measured a 25J leadpipe at 13.5". I wonder what length other people measure on their 2XJ horns.

I set the horn on my lap and lean it at about a 30-45 degree angle, so I can easily reach the main slide to pull it. I buffed it tonight and cleaned out the outer slides and it is about smooth enough for this. I even considered installing a kicker lever, but perhaps I'll just learn to lip all the pitches eventually. It's becoming a fun horn. It's just too bad that it doesn't sound like much at home. It sounds glorious at church with the 20 foot ceilings, but I can't get there to practice all the time . . .