Shires valve differences

[WiltshireBone]

Can anyone tell me the differences between Shires rotary valves - their standard "rotary" and the "dual bore"?

Would be interested to know any bore size differences and how that affects response, or sound.

I am used to a Conn 88Gen2 model with a larger .562 bore through the valve, which plays pretty well on the F section, much better than the earlier Elkhart style models.
I only just discovered that a Bach 42BOG I recently purchased has an undersized valve (the same as the Bach 36) - and indeed whilst I like the bone, it isn't as open as I'd like through the F section - though seems ok through the Bb.
The Shires models I've played with the dual bore seem ok through the F section but not perhaps as open as the Conn.

Anyway, I'm still speccing up the Shires, so would be interested in understanding the difference between their two rotary valves.

Many thanks.

[Matt K]

While the 36 and 42 share the same rotor, they both have .562 tubing, making it "oversized" for medium bore horns, although I'm aware of only a few exceptions where medium bores do not have a .562 bore size as well. So the Bach 42 rotor is not undersized although there are some unique choices with how the receiver interfaces with the rotor which I'm failing to recall at the moment.

Unfortunately, I don't believe I've ever seen any specifics for the dual bore rotor. However, back on TBF, which we have a partial archive of, Ben Griffin, at the time their salesperson, indicated this:

The dual bore rotor's tubing is "stepped" like a dual bore slide. The return tubing (and valve port) is larger than the outgoing tubing. This provides a very solid "locked in" feel to notes in the valve register, much like a dual bore slide. It really roars! The sound also has a very focused and tenor timbre to the sound.

This valve have been extremely popular with people wanting the sound and feel of a rotor but not willing to give up performance in the trigger range.

I hope this description makes sense.

Ben

Incidentally, you might want to read through that thread. Ben did a fantastic job at detailing some of the more detailed aspects of the equipment there. In particular from here:

Quote from: Duffle on Apr 09, 2017, 08:40AMMy main focus was on the 7 and 8 red bells and how they compare with other Shires red bells. They don't seem to be as popular as the 7 Y and G models or some of the other red bells. I was wonder why that might be and what their playing characteristics might be. I know solder in the rim makes a difference but why for example are folks playing the 2RVE more then the 7RLW or 8RLW?.....

Generally speaking, red bells have a much more flexible timbre that is less stable than either yellow brass (which has more high overtones in the sound at low dynamics but changes very progressively as intensity and volume increases) or gold brass (which has more emphasis on lower overtones and shifts to upper overtones more slowly, but in a way that shifts middle overtones up while retaining a low overtone, giving it that characteristic gold brass "buzz" at louder dynamics).

Red brass can be both darker sounding than gold brass and brighter sounding than yellow brass, depending on player input and the set up it's paired with. The Ralph Sauer bell is a a red brass type 7 bell, and many people adore it. The 2RVE also remains extremely popular. (Full disclosure: I have one of each bell, I am a red brass fan). The colors you can get our of red brass are unlike either of the other two offerings, extremely flexible and expressive.

The differences between the 2RVE and 7RLW are about what you'd expect. The 2RVE is more flexible, a bit wider sounding, easier to articulate but doesn't quite have the same focus as a soldered bell. The 7RLW is more progressive and "held together" in it's shifts, moving more progressively. It channels more sound forward than a 2RVE, which is a bit wider sounding.

Most people opt for a type 2 bell if they choose unsoldered. The type 8 are thinned more toward the edge of the bell and it looses some core and centering properties. We generally only recommend type 8 bells for people that have very focused sounds that want to soften. They were quite popular for a short while, but with the resurgence of brilliance being acceptable in classical sounds they are less popular than the type 2. (These observations also apply to type 6 bells, only more so).

I believe (my observations) red brass is out of many people's concept of the current american interpretation of western classical music. (Our red bells are extremely popular in Europe). It requires a firmer hand on the tiller to keep from getting too bright when pushing extreme loud dynamics; it seem more people prefer the stability and low dynamic brilliance of yellow brass or the timbral stability of gold brass.

I hope this helps, red bells are a great option and we happily make them for anyone that would like them.

And here:

Speaking directly to valves...

I generally think of the valves this way: Axial and Tru-Bore are the widest sounding and most open feeling. The standard rotor and Dual Bore valve are more focused in core and width. The axial and standard rotor sound and feel a little more diffuse and have rounder edges to the sound, and the Tru-Bore and Dual Bore valve have a more focused, defined slot to the overtone series.

If I may draw an analogy, picture the slot/sound of a note as a road. The Axial flow is a wide, 4 lane highway with the road taper immediately to the grass medians. The Tru-Bore is a 4 lane highway with a well defined curb. The standard rotor is a like a 2 lane road with a wide breakdown lane that tapers to the grass and the Dual Bore is a two lane highway with a well defined curb. This highlights the similarities of the Tru-Bore to Axial and between the rotors, as well as the similarity of the Axial to the Standard Rotor and the Tru-Bore to the Dual Bore valve.

I hope that makes sense. I'll look forward to reading your reply.

[hornbuilder]

Actually, the Bach factory rotor valve "is" undersized for a 42, and the 36. If you put a .562" (or.547") dia ball bearing into the valve ports, a very large portion of the ball protrudes out past the valve wall. Meaning there is a sizable reduction in the bore of the instrument at that point. Doubled when the valve is engaged.

[Matt K]

That depends on what the meaning of the word ‘is’ is.

But yes, that's the exact details from someone who is very much in the know.

[Nerby]

Reviving this because the information was really useful but I have another question.

With all this being said, does the dual bore valve taper from .547 to .562? or does it taper to an even larger number than .562? My guess is the first suggestion.

[BrianJohnston]

bump

[WGWTR180]

That depends on what the meaning of the word ‘is’ is.

But yes, that's the exact details from someone who is very much in the know.

Well actually Matthew IS correct. You regarding the undersizing statement? Not so much.

[FOSSIL]

Talking about Shires valves, our principal trombone has written off his Greenhoe Conn and is trialling several trombones including a new Shires. I was very surprised to see that the rotor is much smaller externally than they used to be. Looks like old fashioned traditional rotor to me.
Chris

[spencercarran]

Actually, the Bach factory rotor valve "is" undersized for a 42, and the 36. If you put a .562" (or.547") dia ball bearing into the valve ports, a very large portion of the ball protrudes out past the valve wall. Meaning there is a sizable reduction in the bore of the instrument at that point. Doubled when the valve is engaged.

My understanding is that the F attachment tubing wrap is 0.562. You're saying that the rotor ports don't match that? Is there a reason why someone would do that deliberately, or is it just an oversight somehow?

[BGuttman]

Actually, the Bach factory rotor valve "is" undersized for a 42, and the 36. If you put a .562" (or.547") dia ball bearing into the valve ports, a very large portion of the ball protrudes out past the valve wall. Meaning there is a sizable reduction in the bore of the instrument at that point. Doubled when the valve is engaged.

My understanding is that the F attachment tubing wrap is 0.562. You're saying that the rotor ports don't match that? Is there a reason why someone would do that deliberately, or is it just an oversight somehow?

You'd have to ask the guys who designed the 42 back in the day.

Bob Osmun, when he used to offer his rotor boring service, said he had measured the ports as oval and the smaller dimension was 0.515". I can't confirm this, but the Bach 42B had a reputation for being "tight". This was the reason Ed Thayer invented his valve, which started this whole valve fetish thing.

[hornbuilder]

Here is a picture of a Bach standard rotor valve, with a .562" steel ball in the port. As you can see, there is a fair portion of it not contained inside the geometry of the rotor port. ie, the bore of the port is noticeably smaller than the bore of the slide.

[hornbuilder]

To answer the question about this potential "oversight". I don't even think it was a consideration. The desire was there to put a valve on the trombone, and a suitable valve was sourced/made. Every other instrument that used rotor valves used undersized ports in the rotors (up to that point anyway, many still do today) and so a similar valve was used for trombone.

It got the job done. Until Ed Thayer showed 50 years ago that there was another option that made a trombone feel more similar on both Bb and F sides of the horn.

[Matt K]

That depends on what the meaning of the word ‘is’ is.

But yes, that's the exact details from someone who is very much in the know.

Well actually Matthew IS correct. You regarding the undersizing statement? Not so much.

And admitted by me as such!


It's a little surprising to me that it wasn't until the A47 came out that they didn't just use a different rotor. You'd think they would have just quietly started using a different rotor at some point... especially with the mergers that went on over the years. They obviously didn't mind re-using the same part for various horns, after all. And Thayers were quite popular in the 80s/90s. Seems like the obvious choice, especially to the "bean-counters", would be to consolidate all that. I guess on the other hand, I like mine enough that I put it on a Shires, so maybe they thought it better to have an open and more restricted option or something.

I'm assuming the 50 valve has a similar depth (probably 525 ish if the 562 is 515? Or are they supposed to be 592 which assuming a similar difference would be 545ish?).

EDIT: Haven't had my coffee yet.