How to assess thayer valve compression

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Wilco
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Joined: Sun Mar 24, 2019 6:54 am

How to assess thayer valve compression

Post by Wilco »

My shires thayer valves seem to have a good compression, but how to be sure? Is there a procedure for it? Valves have a big pop when I pull the tuning slides...
Specialk3700
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Re: How to assess thayer valve compression

Post by Specialk3700 »

Big pop = good compression
Engineering student with a trombone problem.
Edwards B454
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Burgerbob
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Re: How to assess thayer valve compression

Post by Burgerbob »

Pull a valve slide, wait a few seconds, then press the valve. Still a good pop? The longer, the better.
Aidan Ritchie, LA area player and teacher
Wilco
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Re: How to assess thayer valve compression

Post by Wilco »

Thanks! 2 seconds: good pop. 4 seconds mild pop but still audible. Steady hiss sound after I pull a slide
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Burgerbob
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Re: How to assess thayer valve compression

Post by Burgerbob »

Sounds pretty OK to me.
Aidan Ritchie, LA area player and teacher
Wilco
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Re: How to assess thayer valve compression

Post by Wilco »

Burgerbob wrote: Wed May 08, 2019 2:11 pm Sounds pretty OK to me.
I checked my xeno bass as well, and there is a strong pop is still there well after 4 seconds. Is that a rotor thing??
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Burgerbob
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Re: How to assess thayer valve compression

Post by Burgerbob »

They probably just seal better than your Thayers. It's easier for a rotor to do that, much less surface area to deal with.
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MTbassbone
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Re: How to assess thayer valve compression

Post by MTbassbone »

A tech I went to a while back used a magnehelic gauge to measure the pressure. Not sure if this is correct way or not. I am also not sure what an acceptable reading is either.
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