Rose brass for tubas?

[MartyNeilan]

I have stayed out of serious discussion on this topic, but as I was just practicing on my bass trombone (rosebrass/goldbrass bell and tuning slide) I felt I must interject.
Perhaps, perhaps perhaps, there is minimal discernible difference on the tuba. On the tuba, the bell makes up a disproportionately small percentage of the length of the instrument compared to the trumpet and trombone.
On many instruments, including the trombone, there IS a noticeable difference. Maybe not a 10% difference, but even if there is a .1% difference in sound it most definitely IS there. This is not snake oil. Maybe it has nothing to do with the weight, density, specific gravity, or astrological sign of the brass. I am not a physics professor.
On trombones, the redder the bell is, the more the sound is progressively darker at low to medium volumes and edgier at higher volumes. Thinner bell tend to increase these tendencies further. This is not just one person's opinion, but an industry consensus. Even changing the type of brass used on the tuning slide makes a slight alteration in the tonal quality of a trombone. I don't know why and don't pretend to know, but it does happen. Master trombone makers such as Shires, Kanstul, Rath, and Getzen/Edwards know this and produce a wide variety of bells to cater to a diverse clientele.
Perhaps the weight and diameter of the tuba negates the material. BUT that does not mean that material means absolutely nothing based on one or two specific measurements of it.
-end rant-

[iiipopes]

Yes, bloke, the horn probably played badly, but your conclusion is one of substituting a subjective conclusion based on the "I see nothing...therefore there is nothing" fallacy rather than on a conclusion that some other factors, probably including not being well put together, masked or overshadowed any minor effects the materials themselves had.

I have to believe that a car painted blue might have some speed advantage or disadvantage over a car painted yellow...

...' measureable? ...' worthy of discussion?

As we descend from the ridiculous to the sublime, you tell me: in 1957 a Jaguar D-type driven by the Ecurie Ecosse Scottish racing team, painted a dark Scottish blue, won Le Mans, and among the cars it beat was another Jaguar D-type driven by a Belgian team, painted YELLOW.

[Chuck(G)]

As we descend from the ridiculous to the sublime, you tell me: in 1957 a Jaguar D-type driven by the Ecurie Ecosse Scottish racing team, painted a dark Scottish blue, won Le Mans, and among the cars it beat was another Jaguar D-type driven by a Belgian team, painted YELLOW.

What this tells me is that Belgians have a poor sense of style. Everyone knows that RED cars go faster...

[iiipopes]

And if that wasn't bad enough, the 3d place car that year, also a D-type (they lined up for the last couple hours of the race and finished 1, 2, 3, 4 & 6) was a French team, in sky blue! I wish I could have seen that: Dk blue, Dk blue, sky blue, YELLOW, red Ferrari, BRG D-type....

Oh, BTW: it is very hard to carry a tuba in a D-type, it's "civilian" version the XK-SS, or an E-type, because the boot of a D-type is for show only to carry the obligatory spare tire along with all the "street legal" equipment to qualify as a "sports" car, an E-type boot is not really any larger, just opens on top as a normal lid, and the seats are really narrow.

[windshieldbug]

a Jaguar D-type driven by the Ecurie Ecosse Scottish racing team

So how do you explain the inability of the Scotch to spell "racing team"?

[burger2go]

I know this is an old post, but Kanstul is now offering York Alloy Rose Brass. It is the Lost formula from the J.W. York tubas! Took 1 year with a Super computer at the National Copper Association, two tuba playing metallurgists, four original York tubas.

Hmmm.

Rick - Density is not the whole story. When the metal in a bell is worked, it becomes tempered. Each alloy develops different crystalline structures in the tempering process, and thus will behave differently during resonant periods.

Also keep in mind that the resonant acoustical energy moves through the horn in at least two ways - as a standing wave moving at the speed of sound and as vibrant sound waves moving through the horn at 10 times the speed of sound. The design, bracing, thickness and arc of the bows all have an impact on these vibrations. In instruments with few bends and braces - a trombone - the impact of the vibrant energy in the horn is very significant and measurable (refer to Vincent Bach's thesis on acoustical metallurgy). On instruments with lots of bows and bracing, it can be less so. This is one reason Larry Minick modified the turns and bracing, to allow a more freely vibrating horn (and unrestricted air column).

Builders have been working on alloy compositions for hundreds of years, and the results of their trial and error can be seen in a spectrographic readout. Hard to do on a tuba, but it is easy with interchangeable bells on trombones with detachable bells. I got to do this at the Boosey factory in the late 90's, and was amazed at the different acoustical signatures that a change in 15% of the copper content will have at the same sound pressure levels. They has set this up in their prototype area - got to play an F tuba that had just been set up for Roger Bobo using it - and I had no idea the results could be so dramatic. I can't say that bell material alone makes nearly the difference on a large heavily braced horn - but I would bet it does.

Eric Burger

[hup_d_dup]

Hmmm.

Rick - Density is not the whole story.

I think you are talking to a ghost of tubas past. I haven't seen any posts from Mr. Denney in a while.

Hup (who used to enjoy reading Rick's messages) _d_Dup

[tbn.al]

Rick's back, or at least not a ghost. He has posted a few times this summer. I believe he addressed his absence in one of them.

[dwerden]

Adams offers both yellow brass and gold brass, the latter having more copper content. But I'm not sure what exact ratios would quality any horn as rose brass.

http://www.adams-music.com/wf/instruments/tuba

[burger2go]

Kanstul is now building Tubas with the "York Alloy Red Brass" after a few years of research. I hear they sound delightful.

[ghmerrill]

Adams offers both yellow brass and gold brass, the latter having more copper content. But I'm not sure what exact ratios would quality any horn as rose brass.

I recall seeing somewhere (within the past year or so) some document that gave the proportions of 70% copper for yellow brass, 80% for "gold" brass, and 90% for red/rose brass. But I don't remember exactly what that document was. However, given the softness of the Cerveny 781 I had, I'd be inclined to believe the 90% figure. Of course, I'm sure that everyone who makes these things uses slightly different alloys.