Metallurgy question: Brass, or "Goldbrass"

JCradler · Post by **JCradler** » Mon Jul 26, 2004 8:53 am

Aside from the color and different metal composition of regular yellow brass and the so-called "goldbrass' offered by some manufacturers, is there a sound/response/durability difference(real or perceived) between the two? I mean, the goldbrass costs more, so it must be better, right?

I've also heard this difference referred to as yellow vs. red brass.
I'm curious as to what folks know/think on this, thanks,

JC

Lew · Post by **Lew** » Tue Jul 27, 2004 10:21 am

I had a Cerveny stencil that was equivalent to the 686 but all in "rose" brass. Besides being what my wife called the "pretty pink tuba," it seemed to have a warmer sound to me than the yellow brass equivalent that I tried. Of course the difference could have just been sample variation, but there was a discernable difference. It was a great horn for small groups, but didn't have the projection to support a large band, so I replaced it with a (new) King 2341.

CJ Krause · Post by **CJ Krause** » Thu Jul 29, 2004 1:31 pm

Chuck(G) · Post by **Chuck(G)** » Thu Jul 29, 2004 8:03 pm

Golly, and here I was just comenting to my flautist wife that we tuba players weren't at all like those silly fluties who endlessly discuss the merits of 14Kt gold versus 10Kt gold versus silver versus palladium versus platinum.

Now, I've got to take it all back.

I guess I should get ready for jeweled valve buttons...

imperialbari · Post by **imperialbari** » Fri Jul 30, 2004 1:20 am

Common wisdom within the horn world seems to be, that yellow brass is the best middle of the road material.

Gold brass has a warmer sound (in my vocabulary that is a better alignment of overtone strengths with no single partial being remarkably strong) in lower and mid-strong dynamics. Whereas gold brass instruments tend to break up earlier in louder dynamics. Gold brass trombones tend to be very good in "collecting and unifying" sound and intonation in sections and small ensembles.

Nickel silver (basically a brass with a significant nickel component) is said to give brightish sounding instruments in the lower dynamics, whereas they tend to stay composed and in louder dynamics.

In the US that picture has been blurred a bit, as the most popular nickel silver horn model, the Conn 8D, has a huge volume to its bell throat and the bow leading up to it.

I have the brass version, the 28D. If I play it on its Bb side in the mid-range at low dynamics, it comes close to a euphonium in sound. For me the Bb side works best in the upper range.

As for the discussions about gold qualities in flute making (and also in jewelry making) they tend to focus far too little about the non-gold components of the alloys.

Pure gold is far too soft for any practical use. When the South African government tried to hawk off rands through our banks some twenty five years ago, it admitted that the 24K coins had a nickel content of 0.01 percent just to prevent the coins to wear away between ones fingers.

A 14Kt gold alloy has a non-gold content a bit over 40%. A 10Kt ally has a non-gold content of close to 60%.

In a musical context I could imagine noticeable differences depending on whether the alloy metals are silver, copper, or nickel.

Klaus

Lee Stofer · Post by **Lee Stofer** » Fri Jul 30, 2004 5:43 pm

Gold brass, rose brass, (or goldmessing, auf Deutsch) is softer than yellow brass, which has more zinc and less copper in it. It therefore dents easier, and also cannot be used to hydraulically form branch tubing. So, rose brass or goldbrass instrument components have to be hand-made, the old-fashioned, more labor-intensive way. This, and the fact that this alloy is more expensive than yellow brass to start with, is why the instruments cost more. Gold brass also is much more resistant to red-rot corrosion than yellow brass, because there is much less zinc in the alloy. Red rot is a condition where the bacteria from our breath breaks down in the leadpipe, etc., and the resultant acid eats the zinc out of the alloy, leaving spongy pink patches in the brass that become holes.
Is gold brass better? That all depends upon your playing situation and needs. For most playing situations, a good instrument made of yellow brass is more than sufficient. For schools and other institutional situations that have instruments, I'd suggest yellow brass instruments because of their relative dent resistance, but with rose- or goldbrass leadpipes for corrosion resistance.
I have a gold brass bass trombone, made by Thein in Germany. I can play a note at a pp level on stage, and the note penetrates the entire hall at this pp level, which is quite a different feel from that of a yellow brass instrument. On the other hand, I have noticed that rose brass instruments cannot generally be played as loud without the sound distorting and breaking up as their yellow brass counterparts can. To even out its tendencies, I had the Thein brothers build this bass trombone in goldmessing so that it had the maximum sweetness of response and darkness, and as large as possible so that it could produce a large volume also. The result is a very blending bass trombone that can also be played loudly with a desirable sound.
I have played one Mirafone 188 that was made of rose brass and nickel silver that was one of the most amazing instruments I've ever played, and a few other instruments here and there that just blew me away
Try out different horns, and if the gold brass is "your" sound, you'll know it. By the way, there is a difference out in the hall, too, albeit sometimes subtle.

winston · Post by **winston** » Sat Jul 31, 2004 2:29 am

JCradler · Post by **JCradler** » Sat Jul 31, 2004 9:04 am

winston wrote:What does raw brass do with the sound compared with gold brass and yello brass?

I think the term "raw" means unlacquered/unplated. I suppose that could apply to any type of brass. I've heard some say that unfinished(raw) horns respond more freely than finished ones, I'm guessing it would also brighten the sound.

imperialbari · Post by **imperialbari** » Sat Jul 31, 2004 9:33 am

winston wrote:What does raw brass do with the sound compared with gold brass and yello brass?

Raw brass is either yellow brass or gold brass (or nickel silver for that matter).

What you probably hint at, may be the difference of coated (that is silverplated or lacquered) brass and bare brass.

Some of the engineers and scientists of this forum have written extensively on that topic.

But then these coatings mostly come into play on the outside of the instrument and most often 3/4 or so of the inside length of the bell.

However different sources deliver sheet brass adhering to various standards. That has an influence on the brass instruments made of these different brasses.

I will try to repeat myself as briefly as possible:

Until very recent decades the brass instruments' industry generally could or would not afford special alloys, so they went with the national standard brass for military riffle munition cartridges. The powder chamber shouldered cylinder, not the bullet or the bottom plate.

The absolutely worst standard, technically seen, was the one of the US. Which helped the US instrument makers produce superb trumpets and trombones. Some also would say, that the old tubas and sousaphones belonged to that category.

So the grain structure and its derivate surface structure are influential.

A sample may be added:

Some VERY old European church organs had unique sounds, but were badly in need of restauration to be fully playable.

The organ builders recreated broken or corroded pipes to the best of their knowledge in the original alloys, often tin (Sn) and lead (Pb) being the major components.

But the results did not match the original pipes, so further research was undertaken. That revealed differences in the surface structures of the old and new pipes.

The sheets for the new ones had been rolled to the specified strengths according to modern standards. The old pipes were made from less dense and less perfect sheets.

The research revealed, that these sheets had been cast on-site in the churches. Bad by technological standards, but very good for sound.

Klaus

CJ Krause · Post by **CJ Krause** » Sat Jul 31, 2004 11:09 am

Chuck(G) · Post by **Chuck(G)** » Sat Jul 31, 2004 12:03 pm

winston wrote:What does raw brass do with the sound compared with gold brass and yello brass?

Here's a paper that perhaps has more solid evidence than I've seen elsewhere:

http://www.acoustics.org/press/133rd/2amu4.html

Admittedly, it's for a trumpet model, but there are some noteworthy items.

Lacquer does seem to have more of an effect at high volume levels than an low--and also has less of an effect at low frequencies than high.