Fixing stuffy low register

[chronolith]

As I am out shopping instruments for the past few months I sometimes come across the odd horn that just has a stuffy low register. It is not specific to any make or model of horn that I have tried. Seems to be random. I characterize the stuffiness thus:

- Fairly easy to play soft and low, perhaps easier than it should be
- Middle volume can be terribly hard to nail down for intonation, like the stuffy quality is pushing me out of tune
- Loud works ok for tuning but gets edgier than the non-stuffy horn
- There is "pushback" on the air that wants to interrupt the buzz
- Easy to overblow

For any of the horns in the sample, this issue was not evident in other registers (apart from one which I am calling an outlyer). The pushback feeling on the air is the part that bothers me the most. I am willing to believe that I am the problem and that practice will fix the issue, but in my experience it is something I can track down to an individual instrument when allowed to play side by side. In other words I can reproduce it.

My question to the masses is whether or not the stuffy low register is something than can be fixed or even quantified? Is this something I can take to a repairman with a decent expectation of opening things up a bit? Has anyone experienced and remedied an issue like this? When it comes time for me to buy my next horn I would like a better sense of what my options might be. I don't want to immediately pass on a horn if it is something that can be addressed.

Thanks.

[bort]

Any chance it could be the mouthpiece (or the shank size of the mouthpiece)? I've tried some very nice tubas that are mouthpiece sensitive -- use the wrong piece and it's a real turd of a horn. Use the right piece, and it's great.

I think it also depends a little it on how you approach the low register. On some tubas you can really just blow through it, and blow the crap out of it. On other tubas, that won't get you anywhere good.

But I know you're a serious enough player that you know this stuff already, so just blame it on the mouthpiece like the rest of us.

[chronolith]

The more I play the tuba the less I am convinced there is a perfect mouthpiece, or truly such a thing as mouthpiece sensitive horns. But I admit that I did try everything in my arsenal to attack the issue. There were small variations of course but nothing that actually "cured" it. The best I could find for stuffy horns in my case was a Laskey 30G which seemed to shift the compression more towards the mouthpiece and allow me a little better control of it, but far from a solution. For the purpose of the experiment I am ruling out the mouthpiece.

[Jess Haney]

I know from personal experience a bad valve alignment can have terrible effects on a horns low register. The extra resistance by the valves causes the horn to be hard to "focus" in the lower register. This can be especially true with the larger Besson styled compensators. As you make the second pass through the valves the alignment makes the horns response even worse if the valves are misaligned. My Willson 3100 "which is a 5 valve model" had a terrible valve alignment after several years of the pads and felts compressing down, so therefore the horn over-shot and under-shot the up and down-stroke. This made my pedal B and C natural hard to negotiate and I had to really focus it to make it what I wanted.
So then I get my horn cleaned and the valves aligned, it was like a different horn that I had to get used to all over again. My low register was like the day I bought the horn but I had to get reacquainted with certain other notes because the resistance I had was no longer there. I was confused because, the resistance that I was playing with, I had not even noticed made some of notes in the upper registers easier to play, slot, and sound in tune. Resistance can be a tricky thing to determine, especially if you are not aware that you have been playing with it on your horn because it has been developing over time. But for a horn you just pick up, theoretically a new horn would be in tip-top shape, and a used horn that is broken in will have its own playing characteristics. A bad valve alignment will however effect response in the pedal zone.

[chronolith]

Hmmm. Is there a way to do a rough spot check of the alignment on the show room floor that does not involve a snake cam or horn disassembly?

Thanks for the comments.

[scottw]

Something I had not known was that dents on or near the tuning slide will have the biggest impact on the low register. Matt Walters told me that, after he removed some decent-sized-but-not-huge dents. And, I saw immediate improvement, even with some dents still in play [those much more difficult to remove]. Just a thought to consider.

[royjohn]

Hi Chronolith,

I pretty much agree with KiltieTuba that you can't know at the outset what the cause of the stuffiness is. You just have to look at the horn and make a guess as to what might be wrong, fix that, assess again and go on to the next probably cause if it isn't fixed. That said, if you inspect the horn you might be able to see whether it's likely that dents are the problem, or crushed felts, etc.

If you're looking at valve alignment, you can take a look at the condition of the felts, washers, etc. If something looks completely wrong, it might be. If one of the valves has felts and washers that look a lot different from the others, it could be way out. If the felts all look worn and crushed, you can assume that they may be out of alignment. Either the upstroke or the downstroke could be out either up or down, but I would think that the upstroke would be most likely to be too high and the downstroke too low as the felts crush. You can try pushing one or more valves down slightly to see if this improves things with open notes, or unscrew the valve buttons a little to get the downstroke on one or more valves to go farther down. If you notice a difference, you may have solved your problem.

If you are looking at horns, I don't see why someone would refuse you if you asked to have a repair person look at a candidate horn. A tech might figure something like this out easily.

If you're wanting to look inside a horn, you might look on ebay for one of those mini cams with LEDs on a long cable. You can get one which will plug into your laptop, with the software and a 10 meter cable for about $21. Folks might look at you funny if you pull it out to "look at" a tuba, but this would probably work great if you know what you are looking for. I'm thinking about getting one of these, so if anybody has one, PM me and let me know how they work.