Heavy valve caps

[Chen]

Could anyone who have experiences with heavy valve caps describe the effects of these, if any? (especially piston valves) thanks! And where can they by bought?

[Lew]

There were extensive discussions of these on the old TubeNet. Someone was making heavy valve caps for rotary valves by attaching a large nut to the bottom of them. Some thought they made a difference.

I have not seen heavy valve caps for piston tubas. My sense is that they would have little to no discernible impact. They may have impact on trumpets due to the higher frequencies at which they play and the smaller relative mass of the instrument, but I would think that on tubas the primary impact would be to make the horn heavier.

[wtuba]

I had a set of 4 made for my Conn 56J, and felt they they made a significant difference; horn was more responsive, response was quicker, centering was improved. In short, the horn just seemed to play better. I sold the horn without the heavy caps, however, so I still have them. I would sell, if anyone was interested....wtuba

[Rick Denney]

There were extensive discussions of these on the old TubeNet. Someone was making heavy valve caps for rotary valves by attaching a large nut to the bottom of them. Some thought they made a difference.

Nearly everyone who tried them thought they made a difference. To me, the difference (at least from the player's perspective) was significant. The question is, was it an improvement?

Any time you significantly change the mass of the instrument, it will change its resonant frequencies and therefore its impedance. The impedance of the brass has a subtle effect on the vibration of the air, very far behind the effect of the impedance of the mouthpiece (it's shape, not weight), the taper design of the instrument, and the player's lips. But, while the difference may not be audible in terms of tone, it was definitely feelable by the player. It affected the response and articulation of the notes. When I compared my Miraphone with and without the weights on the rear caps, it was an improvement for me (the instrument slotted more easily and articulated more cleanly), but a detriment for TubaRay, who tried the instrument during a visit. He's good enough not to need the help they provided, and they made the instrument a bit stiffer, which he didn't like and which held him back. I could hear the difference with him playing, but could not make a quality judgment. Likewise, he could hear the difference in my playing, and understand why I chose to keep them.

I would expect the differences to be inconsistent, affecting one kind of tuba one way, and another kind another way, depending on the characteristics of the instrument. I would expect even greater inconsistency among players, with some liking the effect and others being limited by it. Thus, it should only be tried as a reversible experiment, and in the presence of an impartial judge.

I tried them as an experiment--I have not been tempted to put them on any of my other instruments, but neither did I take them off that Miraphone.

Rick "always skeptical and reporting conservatively" Denney

[CJ Krause]

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[jlbreyer]

How would one try this without marring your caps?

Probably by buying a spare set of caps to use for the experiment.

I would think that soldering or crazy gluing would be at least a semi permanent change.

jlb

[Chuck(G)]

How would one try this without marring your caps?

bbtubaman recommends using a shoe adhesive called "Shoe Goo". It can be found in the shoe department at Wal-Mart.

..or if you've got a tube of butyl rubber caulk (e.g. Lexel) lying around from your last plumbing job, it works just as well (I think Shoe Goo is nothing more than butyl rubber). Tool and clean up with mineral spirits.

I wouldn't trust hot glue to do the job, though.

[CJ Krause]

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[MaryAnn]

What I experienced with horn bells may be applicable.

I own a very lightweight horn, a custom pro model. It always had a thin sound, no matter who played it, with the bell it came with. (screw bell.)
I tried and immediately purchased a heavier weight bell because it made such a huge difference in both the playability and the sound of the instrument. This bell was sold to me by the owner of a triple horn, which is much more massive; we also tried the bell on another horn that was not light to begin with. On both horns, the bell was a detriment.

My theory is...that if your instrument has less than its optimal mass for producing sound, that the addition of weight will improve it. If it already has optimal mass, the addition of mass will be a detriment.

MA

[Rick Denney]

My theory is...that if your instrument has less than its optimal mass for producing sound, that the addition of weight will improve it. If it already has optimal mass, the addition of mass will be a detriment.

The only argument against your theory would be that there is no such thing as an optimal mass for an instrument, which is unlikely. Consequently, you theory is likely to be true. The problem is that in practice, it's awfully hard to determine the optimal mass.

Rick "who also thinks the location of that mass may have an effect" Denney

[DonnieMac]

As Rick Denney wrote, "Any time you significantly change the mass of the instrument, it will change its resonant frequencies and therefore its impedance. The impedance of the brass has a subtle effect on the vibration of the air, very far behind the effect of the impedance of the mouthpiece (it's shape, not weight), the taper design of the instrument, and the player's lips. But, while the difference may not be audible in terms of tone, it was definitely feelable by the player" Wow, is he right on!
Dr. Fred Young had me play into a mike coupled to his laptop running a sonic spectrum analysis program. The tuba was a Eb Nirschl. THe fundamental was very weak up to about teh 3rd harmonic. I'd play Eb and the G above would be very apparent on the curves but the Eb much less apparent. So I had Bob Reeves build up some 4 anchors that thread into the center holes in the bottom caps. (It's a piston horn.) The result is a very big difference in tone centering and bigger fundamental. I place the heaviest anchon on the 4th valve bottom cap. There it sounds best to me.