Fix for intonation on old Conn BBb?

[Wilco]

I discovered with my melton 6/4 bb kaiser that it does not want to resonate the F at the correct pitch. When i give the F strongly as input the intonation is right on.

[iiipopes]

I recently bought a 1957 Conn 20j from Dillon Music. It plays very well, but has the typical 20j intonation. The bottom-space F wanted to come out 20 cents flat. To lip it in tune, I had to squeeze so much, the sound would thin out. Fingering it 1st and 3rd was out because I needed to leave the third slide out pretty far to get the low C's and B's reasonably in tune.

When I held that note, I felt around to see which part of the instrument vibrated the most. It seemed to be the main tuning slide. I bought a package of lead tape, 1/2" X 75", and wrapped it around the crook of the tuning slide. That F is now in tune. It may be that I'm just lipping it to where my ear wants it to be, but it is much easier and sounds just as good as the other notes, not pinched.

The rest of the horn's intonation does not seem to be affected. I cannot claim this is scientifically valid, but I believe it is a significant improvement to the horn. I would like to learn more about nodes and anti-nodes and if additional bracing can improve this instrument.

I just did that with my King bell-front bari/euph. Open 2nd line Bb was flat. I could really feel the vibration in the offside ferrule. Yes - out came the lead tape. The Bb is now almost in tune, and the entire instrument seems to have a little better depth of tone. Next week it is going to the tech to make sure there is not a leak there.

[Frank Ortega]

I've seen Martin Wilk do wonders with old Conn intonation by adding a tapered tuning slide.

There may be some other magic involved, but I do know that most horns play better when he's done with them!

My two cents,
Frank