Late nite "tangent" that's somewhat of a serious question that I thought would be worth discussing:

What's the difference in sound (or response etc) between lets say an all yellow brass trombone of the same size as a say red brass bell with gold TS & nickel silver slide (Let's say the red/gold/nickel is comprable to the yellow brass) ? Do the red brass/gold/nickel cancel each other out and result in a yellow sounding instrument, or do they combine and create a unique sound that differs from the yellow brass. Feel free to throw whatever materials into the fire for discussion, but I suppose i'm looking more for the Copper/Zinc ratio.

My experience with Bach horns, a 42B and a 50B3.

Putting on a nickel slide crook seemed to provide a little more core and focus to the sound. It also seemed to allow the beginnings of notes to speak a little more easily.

Putting a gold brass tuning slide crook from a 47B onto my 42B allowed more middle harmonics in my sound, and kind of “tamed” some of the “raw” sound that can happen at extreme loud dynamics.

I have a gold bell for my 50B. I like it… and sometimes it’s too much dark and woofy. I put a sterling sliver leadpipe in the slide, and I found that initial attacks are much cleaner. That also holds true with my yellow Corporation bell. Notes seem more stable as well.

My 2 cents: different alloys can change the response, and they seem to change the overall “harmonic profile” of the horn.

The classic Bach combinations are heavy yellow slide/yellow bell and LW nickel slide/gold bell. In my experience they don't cancel each other out to create a single "Bach sound." Both are recognizably Bach but with noticeably different characters. The nickel/gold combination tends to be more transparent, with a bit less of a punchy core in the middle of the sound.

If anything, the slides sound more different than the bells in the case of Bach, but as in anything YMMV.

For me the different materials don’t cancel each other out. Rather they create a more complex and colour full sound.

My current setup is a greenhoe gb4 with yellow bell, gold brass tuning slide, yellow slide with nickel crook and seamed copper leadpipe. When I was trying horns ( tested alongside a shires NY & Shires Chicago) I kept on coming back to the greenhoe, but it was a tad bright with the greenhoe leadpipe. With the copper I had ‘magic’. I still had all the yellow bell characteristics, but the leadpipe added complexity and colour to the sound that to me was perfect.

I recently added the gold brass tuning slide and that changed the sound as well. I get a bit more warmth - like a gold bell - but still keeping the characteristics of the yellow bell.

So for me, the different combinations don’t cancel each other out, but rather create a more complex sound.