Rotor valve direction difference explained (?)

[T. J. Ricer]

Hey Guys,
Since the question of rotary valve direction has been brought up and shot down a few times on this board, I thought this video might be of interest, as it does a better job of explaining things by using a cut out valve to show the concept. It is not so much the direction the valve turns that is the issue, as which port the air enters on the valve. Clear as mud?

As always, feel free to believe or disbelieve that this would make any noticeable difference.

http://www.youtube.com/watch?v=R93fvioIZ28

the discussion of valve direction happens at 1:45

--T. J.

[bloke]

If you notice, the video is jerky when the valve is restored to its original position, because there is an instant on the return when the air is blocked off.

Other problems are that 1/ everything up to 1:30 is pure nonsense, and 2/ I just don't know any professionals who play Yamaha symphony bore tenor or bass trombones except for one person I know (due to a celebrity player relative) to whom one was given.

Thanks for posting the youtube link, though.

[goodgigs]

At 2:22 the words contradict the video. The ports are not totally "blocked off".
They didn't show the release of the valve because it would assume the exact same position on the far side port as the "bad" example, shown later.
In my opinion there is one good reason to consider rotational direction.
The air flow will be reversed in some part of a rotor either in up or down paddle position, so that's not it.
A linkage can be built to do anything you want, so that's not it either.
DRAINAGE. I can think of no other.

[Lingon]

...Since the question of rotary valve direction has been brought up and shot down a few times on this board, I thought this video might be of interest...

Thanks for the link. It confirms much of my experiences, that there is really something happening when changing direction, from different trombones and their valves.The internal shape of the valves may also have influence. However valve rotation and impact on a tuba, well that may be for the more experienced but this, as much other stuff, may be something to tinker with.

...I just don't know any professionals who play Yamaha symphony bore tenor or bass trombones except for one person I know...

Hmm, Douglas Yeo, Boston, and Ian Bousfield, Vienna, just to mention one for each, or you may have meant know personally?

[Lectron]

Open wrap and thayer valve FTW

[Lingon]

...Open wrap and thayer valve FTW ...

Hehehe, the open vs closed wrap could be discussed. I believe there have been done flow tests and no noticeable differences could be found. The open wrap is of course easier to make, fewer bends. And it is also a big sales gimmick with better water draining. The Thayer valve, of course it has an impact which also the Hagmann valve has. The sound is clearly different, but is it better or worse than anything else?!
FWIW, I heard rumors that one the big makers now have begun experimenting with different shaped spit valve corks and their impact on the sound...

[TubaTinker]

cynical as it sounds.... After spending over 30 years in manufacturing, machine design, and automation... I find it very difficult to swallow that any manufacturing change is done to improve the product without making it cheaper to manufacture or more attractive to the market. Colleges are pouring out young folks with marketing degrees who don't have a clue how or why something is made the way it is.

I could care less which direction a rotor turns.

Let's get back to 'the gap' or 'silver vs. lacquer'... or the new thread about 'polishing the inside'.

[MartyNeilan]

Colleges are pouring out young folks with marketing degrees who don't have a clue how or why something is made the way it is.

There used to be a saying, something along the lines of, "There is no engineering problem that can't be solved by marketing." I think the auto industry learned this to be false the hard way.

[Curmudgeon]

Colleges are pouring out young folks with marketing degrees who don't have a clue how or why something is made the way it is.

There used to be a saying, something along the lines of, "There is no engineering problem that can't be solved by marketing." I think the auto industry learned this to be false the hard way.

One word: Fiero.

[bloke]

Yeo paid money for his?

[PMeuph]

Yeo paid money for his?

I don't know if Yeo personally footed the bill to his "signature" horn and mouthpiece, but I do know that other Yamaha artists usually buy their own horns (with a significant discount).
_____
What about Pete Sullivan?
http://www.yamaha.com/artists/petersullivan.html

[ghmerrill]

There used to be a saying, something along the lines of, "There is no engineering problem that can't be solved by marketing." I think the auto industry learned this to be false the hard way.

Well, the guys doing the actual design, engineering, and production did (of course they already knew this). But the guys with the marketing degrees, I think, did not -- since many have been rewarded with continuing jobs and benefits supported by tax dollars. I've worked to some degree with such marketing folks over a number of years, and some of them are very good in knowing the features of their products, benefits and disadvantages, and comparing these to competitors' products. But they typically share a fundamental belief and attitude, which is that it doesn't matter what they're selling (from shoes to pharmaceuticals to cars to software to ...) -- they can sell it and that's their job. Not at all unreasonable since that 's exactly what they're trained and hired to do. They are in a sales competition, and not a product competition. The problem arises when these people rise to a level in the company where they then have the power to make design, quality, and production decisions. Short-term sales statistics (linked to the sort of compensation that sales and marketing is driven by) in turn then drive design and production quality decisions with predictable results. And mean time between vice presidents in such situations is probably on the order of two or three years. Then the VP moves on to another similar job -- and another like him is rotated into the vacant position.