TromboneChat

I purchased this instrument lightly used in roughly 2019. Lately I’ve noticed vibrations and thought it might be something loose in the bracing. Turns out it’s coming from the slide. It’s almost like the outer slide has a weird fit on the inner tubes or something, but I’m sure that’s where it’s coming from after a lot of testing since I first noticed it. Usually in the range of 4th line F through most of the next octave. I’ve never played an instrument with this issue. For context, I’ve been playing for nearly 30 years, experience on all size trombones among all the major stock and custom instrument manufacturers.

Anyone ever come across something like this? Any thoughts/recs/suggestions?

While it's happening, have somebody else touch or hold different parts of the slide (and bell) to see what changes it. Also, on the spit valve, change the position of the pin or screw that holds it together. That can change the way a horn plays. And the slide lock would be the first thing to check.

My 891Z does the same thing on a sharp middle C. It’s either something about the tolerances in the slide or there’s something loose inside one of the braces. Stopped doing it most of the time after I changed mouthpieces.

brtnats wrote: ↑Fri May 05, 2023 7:58 am It’s either something about the tolerances in the slide or there’s something loose inside one of the braces. Stopped doing it most of the time after I changed mouthpieces.

If there's loose solder in a brace you can usually hear it just from shaking the part in question.

Do what Doug said to investigate. My guess from all of the above, and the mpc comment... leadpipe. Check how loose the end fit is, carefully expand it (mpc shank - go easy...) if there's too much slop. It shouldn't be hard to get in/out, but should feel like a smooth, no play/piston sort of fit when lubricated. Then make sure it's properly screwed down, with a decent application of tuning slide lube on all the contact points esp around the end.