5th valve placement ideas

[roweenie]

I'm in the process of adding a 4 valve 5J set (.656) onto a small 3/4 Holton E flat tuba, and I'm trying to plan out where best to place a 5th valve.

My question is this: considering the size of this horn (basically an Eb euphonium), does it matter which side it goes on? The large side is considerably larger than the small side (.750 vs. .656). Could that make a difference?

There is plenty of room on both sides of the tuning slide, so that's not an issue. Logistics of the linkage are also not so much of an issue - I'm more concerned with the sonic results of the location.

[roweenie]

After the tuning slide meaning the small side?

[roweenie]

Mark, your horn came out really nice - excellent job!

Elephant, your info is also excellent. I think placing it in the leadpipe would make it (the leadpipe) too short, and there's no room to put it where it's located on Mark's horn, so it's down to either the large or small side of the tuning slide.




Surprisingly, this horn has a rather slow taper, then suddenly narrows down dramatically at the tuning slide, so I was concerned that a valve on the large side (.750) of the tuning slide might actually be TOO big.

[Alex C]

After the tuning slide.

What he said.

[roweenie]

I'm remembering now some conversations I've had with two different tuba design luminaries, both of whom are highly respected in the industry (and by me, too!). They both told me, independently and several years apart from each other, not to mess around with the area between the 4th valve and tuning slide. It's known by some to be a rather sensitive place to make changes to.

I'm supposing this theory is behind the idea of the reverse tuning slide.

Wade, I followed your thread very closely - not only was it educational, but it was also very entertaining. I learned a lot - thanks!

[Peach]

What is the basis behind saying that if a valve is mainly used for low notes it will benefit from a bigger bore?

I'm not saying for a second that anyone is wrong; far from it. I haven't a clue, I'm just wondering if it's a "It just works" thing, or there is some real science behind it?

I see the obvious correlation that trumpet = high = narrow bore. Tuba = low = big bore =)

Thanks for any help!
MP

[roweenie]

Indeed!

I think I've got the picture. Now, to the drawing board.....

Thanks!

[Peach]

Touche Wade! Suppose I was asking for that =)

If it works, it works I guess...