Bach 50B Valve question

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dukesboneman
Posts: 935
Joined: Apr 02, 2018

by dukesboneman »

I recently sold my Yamaha 321 Bass and bought a Bach 50B double trigger.

I love the dark rich sound but the low range doesn`t seem to "POP" like the Yamaha did.

Are Bach Bass rotors as open as other brands? Or do I just need to get used to it?

Thanks
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Burgerbob
Posts: 6327
Joined: Apr 23, 2018

by Burgerbob »

Those valves are probably the worst fitted to most any pro bass, especially one with such a high capability like the 50.

I think there are some random examples out there that are fine as is, but I haven't played one myself. On my last 50B3OG, it made a great sound until I put any dynamic into it, and it started to lose all core and center to the sound. With the Shires rotors I replaced the valves with, it was an amazing instrument.
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dukesboneman
Posts: 935
Joined: Apr 02, 2018

by dukesboneman »

I had really good luck with The Olsen valve on my 42BO

I was considering that option
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Burgerbob
Posts: 6327
Joined: Apr 23, 2018

by Burgerbob »

[quote="dukesboneman"]I had really good luck with The Olsen valve on my 42BO

I was considering that option[/quote]

It's the cheapest, most simple option. I've also had a 50 with olsens that was pretty great.
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tbonesullivan
Posts: 1959
Joined: Jul 02, 2019

by tbonesullivan »

Bach valves for the 42 and 50 are usually considered undersized, especially with respect to the ports. Osmun brass and other companies have offered opening rotor ports as a standard mod for decades due to this. Bach unfortunately has no trouble selling horns with those rotors, so they have little to no motivation to fix the issue, especially when they offer third party valves a nice hefty upcharge.
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GabrielRice
Posts: 1496
Joined: Mar 23, 2018

by GabrielRice »

Some of it is going from a single valve to a double, but I'm also in agreement that Bach rotary valves are rarely very good without modification or replacement.
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Kbiggs
Posts: 1768
Joined: Mar 24, 2018

by Kbiggs »

On my 50, I replaced the Bach rotors with Olsen rotors. Easier to play, more even across registers, and they don’t “back up” in the valve register. I also replaced the after-market Thayers on my 42 with an Olsen valve. Same result.
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hornbuilder
Posts: 1384
Joined: May 02, 2018

by hornbuilder »

I've posted this before, but here is a photo of a Bach 50B rotor, with a .594" steel ball in the port. As you can see, there is a substantial amount of the ball sitting outside the valve port.
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Wilco
Posts: 211
Joined: Mar 24, 2019

by Wilco »

I had the ports opened up. No issues now.
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LIBrassCo
Posts: 585
Joined: Feb 24, 2019

by LIBrassCo »

Metal bell horn here is a corp 50 bell with one of my valvesets. Played quite well, no comparison to stock valves.