Just curious--re. JinBao

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pgym
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Re: Just curious--re. JinBao

Post by pgym »

T. J. Ricer wrote:Not to beat a dead horse, but just in case anyone wants to "feel" the difference that Mark is talking about. . . try blowing (not buzzing) into a tuba that has the rotors set up 2 and 2. First press down valves one and/or two while you are blowing, then push down valves 3 and/or 4 while blowing. There is some sort of "flap-back" feeling when you press 3 or 4 while blowing as they turn "into/against" the airstream. (maybe try 1 and 2 together versus 3 alone, if you think the difference might be slide length).
Which begs several questions, viz.:

do you feel a "flap-back" when you press 3 and/or 4 while blowing, then press down 1 and/or 2?

do you feel a "flap-back" when you blow into the open horn, then press down one or more valves?

if you reverse 1 and 2 to the direction of 3 and 4, do you feel a "flap-back" when you press down 1 and/or 2 while blowing into the open horn?

pgym "who can create a 'flap-back' on a rotor horn (or a piston horn, for that matter), regardless of the rotor setup, by depressing the rotors slowly enough, and therefore suspects that the 'flap-back' is due to the momentary interruption of the airstream as the rotor passes from fully open to fully closed to fully open, rather than the airstream changing direction"
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Dan Schultz
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Re: Just curious--re. JinBao

Post by Dan Schultz »

About the rotors turning one direction or the other.... There's not much air actually moving. Just sound waves. And... sound waves don't care much how much restriction (if any) is present. This ain't water flow were talking about here.
Dan Schultz
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Current 'stable'... Rudolf Meinl 5/4, Marzan (by Willson) euph, King 2341, Alphorn, and other strange stuff.
tubaforce
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Re: Just curious--re. JinBao

Post by tubaforce »

TubaTinker wrote:About the rotors turning one direction or the other.... There's not much air actually moving. Just sound waves. And... sound waves don't care much how much restriction (if any) is present. This ain't water flow were talking about here.
+2, and an "Amen" from the Choir!
Al :tuba:
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