Favorite valve?

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masonsat
Posts: 2
Joined: Apr 22, 2024

by masonsat »

Wondering what valves I should look into for a new horn. I currently have a rotary valve but have heard good things about axial flow. I’ve also heard that hagmann valves work well but require a lot of maintenance. Thoughts?
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BGuttman
Posts: 7368
Joined: Mar 22, 2018

by BGuttman »

First thing to learn: there is no free lunch. Everything has advantages and disadvantages.

Axial valves are more open in the valve register. Some find them too open.

Bach rotors have a history of being too small. Other makers use rotors that are a better size. Yamaha, Conn, Holton, King, Benge, etc. made rotors that worked fine.

Hagmanns are a new technology and are a bit finicky. Some folks have found them to work great with nearly no maintenance, while others have had no end of problems. The valves are more open than rotors but less open than Axials.

Note that different valves are not like tinker toys, where you just choose one and plug it in. Different makers offer different valves. You need to test the whole package to see what works for you. You may find that one maker's product works better for you, even though it may not be the "optimal" set of features.
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Jhonybassbone2024
Posts: 5
Joined: Apr 04, 2024

by Jhonybassbone2024 »

I love Trubore Valves, Greenhoe, Rotax but all new rotary valves are so good
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WGWTR180
Posts: 2152
Joined: Sep 04, 2019

by WGWTR180 »

Too bad the search function doesn’t work. This has been debated multiple times. <EMOJI seq="1f600" tseq="1f600">😀</EMOJI>
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LeTromboniste
Posts: 1634
Joined: Apr 11, 2018

by LeTromboniste »

Hagmanns have been around for nearly 35 years, only 12 years fewer than Thayers, so they're not exactly new technology. They do work fantastic, it's just a question of whether or not you like the feel/blow. They're my favourite valve for Bachs and Bach-style instruments. I disagree that they are high maintenance – you just need to oil them regularly (once a week was okay for me), which you should anyway do with any valve. Because you have direct access to the rotor core, they're easier to oil properly than traditional rotors. They are just maybe a bit less tolerant to under-maintenance than certain other designs. On the other hand they are very easy to disassemble and clean for the more in-depth maintenance when giving your horn a bath.
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elmsandr
Posts: 1373
Joined: Mar 23, 2018

by elmsandr »

Engineering wise, there are several valves that I love that I won’t advocate for… any valve that requires sealing on two different surfaces. Axials (Thayers), Hagmann, Trubores. These are all great valves. They are what leaves the house with me. Nothing else blows or feels like a Thayer. They’re awesome. I have three. If you like/need that blow, go for it.. but if I choose again, I just won’t do it. Too picky. Same with my Trubores. They aren’t as picky as the Thayers, but still a lot more than just a rotor based valve.

Play some, pick what works, play it for a couple of years and see if it actually works.

Andy
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JeffBone44
Posts: 367
Joined: Oct 24, 2022

by JeffBone44 »

I think of a whole horn as a system. All of the parts work together to create a sound and feel that I want. I've liked axials a lot on some horns, and disliked them at other times. Same with rotors. Currently I'm using independent axials on my Shires bass. I liked them so much that I got a tenor axial section, but it turns out that I didn't like that as much, so I'm currently using a standard rotor on my large bore. I just went up to Shires last week and tried the Alessi rotor and loved it. It was nice and open but very stable. The gold F attachment tuning slide gave the sound extra warmth and density.
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brassmedic
Posts: 1447
Joined: Dec 14, 2018

by brassmedic »

[quote="masonsat"]Wondering what valves I should look into for a new horn. I currently have a rotary valve but have heard good things about axial flow. I’ve also heard that hagmann valves work well but require a lot of maintenance. Thoughts?[/quote]
I like Thayer valves. It's the most open blow you can get. If you like a lot of resistance in the valves, then they're not for you. I do have to oil them frequently, which is about once a week, but some players need to oil them even more frequently than that. I clean them about every 6 months.

Hagmanns do require maintenance. They need oil, and they need to be professionally cleaned periodically, and I think that's where players run into problems. The way the parts fit together is rather complicated; a novice is not going to be able to remove and reinstall the valve core correctly. I have run into people who think they can just run water through the valve and that's enough cleaning. That doesn't work. Most of the Hagmanns I work on have gone too long without maintenance and are full of green slime and tarnished black on the surfaces. People tend to wait until the valve starts failing before they do any maintenance. If you don't like getting your instrument serviced, don't get Hagmann valves. But if you are willing to keep up on the maintenance, they are great. Thayers need to be cleaned too, but it's a bit more straightforward to take them apart and put them back together.
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ACman
Posts: 6
Joined: Jan 16, 2023

by ACman »

My favorite sounding valves I've ever tried are the Infinity or Olsen axial flows on a Bach 50AF3. Unfortunately I've never been able to get past the lack of resistance and long throw that axial flows feature. I understand the appeal behind them but I could never get myself to like the way they play. My favorite valves are the Meinlshcmidt open flow rotors. They are very resonant with a super quick throw. The Bach 42OF plays so well with that valve, but unfortunately they don't/won't make a Bach 50 with that same setup.
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boneAngo
Posts: 27
Joined: Jul 26, 2024

by boneAngo »

it depends what style you are (and whether you are playing a bass or tenor).

There are two extremes in the trombone world: American Sound (similar to Joseph Alessi) and European Sound (similar to Jean Raffard)

Both the sounds are great, with different characters and colors.

if you think you have a larger lung volume (american), and you think forcing the lips is comfortable for you to play naturally, Thayer is definitely the best choice for you to play with less effort.

if you think you have a smaller lung volume (european), and you think relaxing the lips and project through the centre of lips is doable and natural, go choose hagmann.

also, the mpc you are using also matters. just go try out the combination suits yourself the best.
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Matt_K
Posts: 4809
Joined: Mar 21, 2018

by Matt_K »

Depends on the rest of the horn and what I'm playing. I played a tru-bore for maybe 2 years and I had a thayer for like a month and have otherwise been all rotors (including my small bores!) for a long time now!
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sirisobhakya
Posts: 445
Joined: Jun 11, 2018

by sirisobhakya »

I have tried only 3 valve types: standard rotor (but from many makers), Thayer/qxial flow, and Hagmann.

Hagmann feels the best, but a good rotor comes very close.
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OneTon
Posts: 757
Joined: Nov 02, 2021

by OneTon » (edited 2024-08-29 10:32 p.m.)

So it could be wrap dependent.
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BGuttman
Posts: 7368
Joined: Mar 22, 2018

by BGuttman »

The issue with (at least) the Bach 36 and 42 is that the same rotor was used for both. Fits the 36 great, but it's really too small for the 42. This is what initiated the search for other valves for the Bach 42 that were less stuffy. I love my 36 with its F-attachment but never found a 42 rotor that I liked. I do like the King 4B/5B, Conn 88H, and Yamaha 682 rotor valves since they are much bigger than the Bach 42 rotor.
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timbone
Posts: 240
Joined: Apr 30, 2018

by timbone »

I have to say maintenance and valve neglect do more to persuade people's opinions. Generally, trombone players are notorious for not taking care of their valves (horn). The Hagmann is a great valve; but requires maintenance since it is such a large bearing surface. That being said, what valve gives you the sound and response you want? I'd start there.
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BrassSection
Posts: 424
Joined: May 11, 2022

by BrassSection »

Spit valve is my favorite, it can make the horn sound much better when used as needed!

Sorry, couldn’t resist that one. That’s the only valve on the trombone I own and use.
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Posaunus
Posts: 5018
Joined: Mar 23, 2018

by Posaunus »

[quote="BGuttman"]The issue with (at least) the Bach 36 and 42 is that the same rotor was used for both. Fits the 36 great, but it's really too small for the 42.[/quote]

In light of all the recent valve developments (and TromboneChat commentary about valves), do we still believe that the Bach 36B valve (introduced in the 1950s?) is optimal? Or even "great"?
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BGuttman
Posts: 7368
Joined: Mar 22, 2018

by BGuttman »

[quote="Posaunus"]<QUOTE author="BGuttman" post_id="249836" time="1722870738" user_id="53">
The issue with (at least) the Bach 36 and 42 is that the same rotor was used for both. Fits the 36 great, but it's really too small for the 42.[/quote]

In light of all the recent valve developments (and TromboneChat commentary about valves), do we still believe that the Bach 36B valve (introduced in the 1950s?) is optimal? Or even "great"?
</QUOTE>

Not in the least. There are probably better valves out there. It's just that a valve sized for the 36 is not optimal for the 42.
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Kdr152004
Posts: 7
Joined: Sep 01, 2022

by Kdr152004 »

I am really enjoying the traditional rotary valve on my new Conn 88HNV. Not as open as a Thayer perhaps but it has a very smooth/quick action and the slight timbre shift is interesting.
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conn88Hagmann
Posts: 492
Joined: Aug 09, 2018

by conn88Hagmann »

The valve fitted to that Bousfield Getzen is I think the best valve I’ve ever played.
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tbdana
Posts: 1928
Joined: Apr 08, 2023

by tbdana »

No mention of the CL2000, huh? Hm. I think it's a great valve.
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Hamby86
Posts: 14
Joined: Jan 15, 2024

by Hamby86 »

[quote="tbdana"]No mention of the CL2000, huh? Hm. I think it's a great valve.[/quote]
It's the valve I've had for 24 years. The short throw is hard to beat and I think it's pretty open especially for a rotary
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Posaunus
Posts: 5018
Joined: Mar 23, 2018

by Posaunus »

[quote="tbdana"]No mention of the CL2000, huh? Hm. I think it's a great valve.[/quote]

:good:
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harrisonreed
Posts: 6479
Joined: Aug 17, 2018

by harrisonreed »

[quote="tbdana"]No mention of the CL2000, huh? Hm. I think it's a great valve.[/quote]

The problem with the valve is that it is prone to mechanical issues (depending on which version of the core you have), it's sensitive to what oil you use, and there's really only one horn you can get it on. It's a great valve when you have it aligned and it's not gunked or starting to corrode.
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Digidog
Posts: 483
Joined: Dec 13, 2018

by Digidog »

[quote="tbdana"]No mention of the CL2000, huh? Hm. I think it's a great valve.[/quote]

[quote="harrisonreed"]The problem with the valve is that it is prone to mechanical issues (depending on which version of the core you have), it's sensitive to what oil you use, and there's really only one horn you can get it on. It's a great valve when you have it aligned and it's not gunked or starting to corrode.[/quote]

The CL2000 is a great valve. My experience is that it's open, quick, operating silently and leaving no artefacts in the sound of the player. I like it very much and it is the valve I prefer for many reasons.

I concur with Harrison, though, that there are some issues.

First: is it still in production, so spare parts or complete valves can be found? Or do one have to have a tech build parts from scratch if something like the rotor or a pin has to be switched? I have tried to purchase a complete valve for my Yamaha 421 through both the European and the Swedish Conn agencies (the 421's valve is worn and in need of replacing), but without any response at all from Conn. I don't see new horns from Conn equipped with the valve either, so it makes me wonder whether the valve is out of production or not.

Second: It is sensitive to particles and depositions. It seems like the tolerances with the rotor are so small that the tiniest particle contamination at the wrong place can upset the function. It is not a big problem, but it has occurred.

The third: The valves on my Conn 62 are between 24-28 years old, and my tech says that there is no corrosion whatsoever on them. I have had no problems at all with the rotors being corroded or eaten by some chemical processes in the valve. However: I can see that the large surface of the rotor top creates a lot of surface where corrosion can occur, so maybe I have to come back in a couple of years with a review on that. I think my rotors are aluminum, but I'm not sure. I have played a CL2000 with a brass rotor and one with some kind of (I think) titanium alloy rotor, and they felt great and had a tremendous heft to their sound, but especially the brass rotor was tangibly heavier.

Over all, I think that the principles and the functions of the CL2000 are great. Had I been able to buy a valve from Conn for my 421, it had been my absolutely preferred choice, but now I'm planning to refit the horn with a Meinlschmidt valve. Then I have to see how the valves on my Conn 62 age, but this far everything has been fine and well, and if the build quality hasn't deteriorated catastrophically and if the valve still is in production, I'd wholeheartedly recommend it; both for a bass or a tenor horn.
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tbonesullivan
Posts: 1959
Joined: Jul 02, 2019

by tbonesullivan »

Does anyone know what the Conn CL2000 valves are made from currently, and what kind of plating / coating is on the cores? Pictures I have seen often make them look like the early aluminum thayer valves, which were cast and had some type of teflon coating. They later switched to machined / milled aluminum with a heavy black anodized finish for the thayers, but I don't know if that's possible for the CL2000 valve.

I did have a bit of erosion on the core of my Thayer valve, but rubbing in a little Hetman slide gel onto the small parts that had corrosion and using Hetman oils has prevented any advancement of the corrosion in over 10 years. At this point I think the bearing will wear out before anything else, and they are not replaceable, so it would then be time to look for a new Axial Flow valve.
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conn88Hagmann
Posts: 492
Joined: Aug 09, 2018

by conn88Hagmann »

So the shires Dual Bore seems really good, . . . But aren’t all Conn, Thayer and umpteen other valves actually dual bore too. If the valve section is .562 then it’s dual bore right?
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Matt_K
Posts: 4809
Joined: Mar 21, 2018

by Matt_K »

Dual bore typically means one of two things:

* The upper inner and lower inner are divergent bore sizes (e.g. 547/562)

* (In the case of the Shires "Dual bore rotor") The valve has two sized internal bores, one for when it's "open" and the other for when its "closed" and the return port is larger than the entrance port.

If dual bore was referring to the size of the F attachment compared to the slide, almost every trombone with an F attachment would be "dual bore". 562 is typical bore size for rotors for medium and large bore trombones.
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conn88Hagmann
Posts: 492
Joined: Aug 09, 2018

by conn88Hagmann »

But alas, Hagmann have 547 bore. . Or at least on my 88H Elkhart that was converted it does. .
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Burgerbob
Posts: 6327
Joined: Apr 23, 2018

by Burgerbob »

Most tenor hagmann installs are .562.
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Matt_K
Posts: 4809
Joined: Mar 21, 2018

by Matt_K »

Yeah, there isn't a term I'm familiar with that describes a lower slide being the same (or very similar) bore to the tubing. King 3B+F have .530 rotors and a .525 tube which is a much smaller difference than .547 with a .562 rotor. Duo Gravis have a .562 rotor/tubing as well as .562 lower slide. I've just head of people describing it as the valves having a matching bore to the lower slide.

Hagmann does have "progressive bore" rotors, which are tapered in the same way a neckpipe does, which is kind of in the same ballpark as Shires dual-bore rotors. Hagmann also has about the largest, if not the, largest offering of bore sizes, FWIW. They offer down to .530 and well into the .600s for things like Cimbasso. Getting a pair on a small bore is on my bucketlist for when I win the lottery.
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timothy42b
Posts: 1812
Joined: Mar 27, 2018

by timothy42b »

[quote="Matt K"]Yeah, there isn't a term I'm familiar with that describes a lower slide being the same (or very similar) bore to the tubing.[/quote]

Constant bore.
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Posaunus
Posts: 5018
Joined: Mar 23, 2018

by Posaunus »

In another thread, Sesquitone (Benny) makes the case that the F-attachment tubing I.D. (and valve ports) should be the same as the slide bore.

He knows ten times more about this than most of us do.
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Sesquitone
Posts: 291
Joined: Apr 25, 2022

by Sesquitone »

[quote="BGuttman"]Axial valves are more open in the valve register. Some find them too open.[/quote]

I see this comment a lot. And similar comments such as "it depends on how much resistance you want in a valve".

There is no such thing as "too open". Ideally, there should be no more resistance in the valve block than there would be in an equivalent length of straight tubing (of the same bore as the surrounding tubing).

Tailoring "resistance in a valve" (by selecting different makes) is equivalent to putting a good sized dent in the gooseneck of a valve-free trombone. I doubt that anyone would contemplate that. The real "resistance" felt by the player should come from the profile of the instrument itself—especially what happens within the mouthpiece and lead-pipe section. This is where genuine "resistance" can be modified (a little).

Just like a big dent, most (what-should-be) unwanted resistance in a valve comes from discontinuities in the cross-section of the sound-path, like very sharp bends in the knuckles, rotor (or other geometry) channels or ducts that are too narrow (or too wide, creating little "chambers" that act as Helmholtz resonators), other sharp changes in gradient in the sound-path profile (e.g. unnecessary gaps—due to sloppy construction—in connections between the knuckles and the surrounding tubing), and (more-often-than-not) poor alignment (of an otherwise satisfactory) valve.

A design that effectively eliminates all of these discontinuities is approaching the ideal described above.

.
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meine
Posts: 397
Joined: Feb 25, 2021

by meine »

How about no valve?
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Sesquitone
Posts: 291
Joined: Apr 25, 2022

by Sesquitone » (edited 2024-08-30 11:24 a.m.)

[quote="Posaunus"]In another thread, Sesquitone (Benny) makes the case that the F-attachment tubing I.D. (and valve ports) should be the same as the slide bore.[/quote]

And this is a different (although related) situation, again. The "customary" design uses an attachment bore that is considerably larger than the slide bore. Even with a "perfect" (zero "resistance") valve and well-made (i.e gap-free) butt joints everywhere, there is then a significant discontinuity in in the bore seen by a sound wave in the vicinity of the slide receiver. This causes major reflections that can disrupt intonation, tone-quality and attack response. It is the major culprit of well-known attachment "problems", especially a flat and "stuffy" attachment second harmonic (F2 on an F attachment)—even though the pedal F1 may be well in tune and of good (pedal) quality—a very sharp and uncentered attachment third harmonic with the slide closed (C3), and the desynchronisation of overtones, which is what leads to unreliable attack response of some attachment notes.

When the attachment and valve bore are reduced to match that of the slide, all of these "problems" evaporate. The alternative of using a larger single-bore, "bass", slide on a large-bore tenor (think Jay Friedman) or a dual-bore slide (with the bore of the incoming arm matched to the valve and attachment bore) that enhances the low range without affecting the high-range brightness (i.e. if you don't have Jay's chops) is another good alternative.

But, to get back on topic, choose the "most free-blowing" valve that you can!
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BGuttman
Posts: 7368
Joined: Mar 22, 2018

by BGuttman »

@Sesquitone: Feel free to spout any theory you choose. The Axial systems were designed to minimize the resistance in the attachment section. From a practical standpoint (and here I talk from experience) you can have too little resistance so the valve seems to require too much air. Perhaps it was because I had been playing rotors for too long before the development of the Axial and I was expecting something that wasn't there. I had to return an axial (Thayer at the time) system because it literally sucked the air out of me.

If you like the feel of an axial, more power to you. I'm just glad we have a choice.
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conn88Hagmann
Posts: 492
Joined: Aug 09, 2018

by conn88Hagmann »

[quote="Posaunus"]In another thread, Sesquitone (Benny) makes the case that the F-attachment tubing I.D. (and valve ports) should be the same as the slide bore.

He knows ten times more about this than most of us do.[/quote]

So that’s what I have on my Conn Elkhart. . . It was a kit from Hagmann in about 2009/10.
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atopper333
Posts: 377
Joined: Mar 09, 2022

by atopper333 »

Plus one on the rotors. I’ve tried two axials and I can’t seem to make em work for me. Probably more me not being as developed as a player as I would want to be…but I do love the rotors I’ve played…except my Holton 602Fs…always kinda stuffy on both of them…
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conn88Hagmann
Posts: 492
Joined: Aug 09, 2018

by conn88Hagmann »

[quote="Sesquitone"]<QUOTE author="Posaunus" post_id="251991" time="1724963620" user_id="158">
In another thread, Sesquitone (Benny) makes the case that the F-attachment tubing I.D. (and valve ports) should be the same as the slide bore.[/quote]

And this is a different (although related) situation, again. The "customary" design uses an attachment bore that is considerably larger than the slide bore. Even with a "perfect" (zero "resistance") valve and well-made (i.e gap-free) butt joints everywhere, there is then a significant discontinuity in in the bore seen by a sound wave in the vicinity of the slide receiver. This causes major reflections that can disrupt intonation, tone-quality and attack response. It is the major culprit of well-known attachment "problems", especially a flat and "stuffy" attachment second harmonic (F2 on an F attachment)—even though the pedal F1 may be well in tune and of good (pedal) quality—a very sharp and uncentered attachment third harmonic with the slide closed (C3), and the desynchronisation of overtones, which is what leads to unreliable attack response of some attachment notes.

When the attachment and valve bore are reduced to match that of the slide, all of these "problems" evaporate. The alternative of using a larger bore slide (think Jay Friedmann) or a dual-bore slide (with the bore of the incoming arm matched to the valve and attachment bore) that enhances the low range without affecting the high-range brightness (i.e. if you don't have Jay's chops) is another good alternative.

But, to get back on topic, choose the "most free-blowing" valve that you can!
</QUOTE>

So would this mean, that a standard 88h (or any that has a .562 valve section) should work better with a 47/62 slide, and my old Elk with the .547 Hagmann should not. . .

(Which is kind of how it feels to be honest).
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hornbuilder
Posts: 1384
Joined: May 02, 2018

by hornbuilder »

[quote="Posaunus"]In another thread, Sesquitone (Benny) makes the case that the F-attachment tubing I.D. (and valve ports) should be the same as the slide bore.

He knows ten times more about this than most of us do.[/quote]

I disagree. I have done the tests.
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Burgerbob
Posts: 6327
Joined: Apr 23, 2018

by Burgerbob »

I have a weirdly large amount of trombones that play great with valves larger than their lower slide tube. Maybe I'm just not good enough to know the difference :)
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Posaunus
Posts: 5018
Joined: Mar 23, 2018

by Posaunus »

[quote="hornbuilder"]<QUOTE author="Posaunus" post_id="251991" time="1724963620" user_id="158">
In another thread, Sesquitone (Benny) makes the case that the F-attachment tubing I.D. (and valve ports) should be the same as the slide bore.[/quote]

I disagree. I have done the tests.
</QUOTE>

Theory vs real world? :idk:
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Posaunus
Posts: 5018
Joined: Mar 23, 2018

by Posaunus »

[quote="Burgerbob"]I have a weirdly large amount of trombones that play great with valves larger than their lower slide tube. Maybe I'm just not good enough to know the difference :)[/quote]

I think my Benge 165F (0.562" F-attachment bore) plays better in the "trigger range"' than the otherwise-similar King 4BF.(0.547" bore).

My imagination?

Wishful thinking?

:idk:
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Digidog
Posts: 483
Joined: Dec 13, 2018

by Digidog »

[quote="Posaunus"]In another thread, Sesquitone (Benny) makes the case that the F-attachment tubing I.D. (and valve ports) should be the same as the slide bore.[/quote]

I disagree. I, myself, have several horns with valve sections larger than the slides they have that plays and sounds great; I have also played many non-matching horns through the years that were absolutely terrific in all regards, so the practice of trombone construction doesn't work that way.

That claim doesn't hold in theory, either. There's no physical law of resonance and/or flow that stipulates correlations in measurements to be necessary for optimal flow and/or resonance. There are so many other factors that affect the efficiency in - and effect of - a flow and/or a resonance, that measurement correlation isn't the one and only determining factor.

[quote="Posaunus"]He knows ten times more about this than most of us do.[/quote]

No disrespect, but knowing and knowing are not always the same traits.
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conn88Hagmann
Posts: 492
Joined: Aug 09, 2018

by conn88Hagmann »

But what you have said, actually means that it doesn’t matter what size the pipes are, matching or not. It’s just how it plays. . Which is fine of course but means no scientific theory at all can be applied. <EMOJI seq="1f937-1f3fb-2642" tseq="1f937-1f3fb-200d-2642-fe0f">🤷🏻‍♂️</EMOJI>
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Sesquitone
Posts: 291
Joined: Apr 25, 2022

by Sesquitone » (edited 2024-08-30 8:29 p.m.)

[quote="Posaunus"]In another thread, Sesquitone (Benny) makes the case that the F-attachment tubing I.D. (and valve ports) should be the same as the slide bore.

So that’s what I have on my Conn Elkhart. . . It was a kit from Hagmann in about 2009/10.[/quote]

Yes, that sounds right. René Hagmann began providing “matched-bore” valve-plus-wrap kits for individuals and commercial manufacturers in the late 1990s. René and I had worked for a couple of years before that trying to discover the reason for and, if possible, to correct well-known “problems” with attachment notes. I had noticed for some time that, except for short notes in rapid passages, professional tenor trombone players using Bb/F instruments in symphony orchestras usually favoured slide-alone (SA) 6th and 7th positions for the four notes (F2, C3, E2, B2) that theoretically could have been played with the valve. When I asked some local professionals (Jim DeSano, Steve Witser, Paul Ferguson, and my colleague at The University of Akron, Ed Zadrozny) about that, I received fairly uniform “complaints” about those attachment alternates, typically: when the F attachment is tuned so that the attachment F3 matches the SA F3, with the slide closed in both cases, the second attachment harmonic, F2, tends to be flat and “stuffy” (even when the pedal is well in tune), the third harmonic (C3) tends to be very sharp and uncentered, and attack response is unreliable. Most of those players “blamed” the valves available at that time. [The Thayer valve had been invented decades earlier but was not in common use. More advanced valves such as the Willson Rotax and the Hagmann valve were just becoming available.] When I contacted Mr. Hagmann about his valve, he confirmed that he had heard similar complaints—which had been motivating factors in developing his very “open” three-internal-duct design. But even then, the problems remained. Something else was going on!

Two facts gave me an inkling as to what might be causing the “problems”. When I had spoken at length with Allen Kofsky (long-time second trombone with the Cleveland Orchestra), he pointed out a couple of unusual things about his trombone, a modified Benge 190: (i) the attachment had been literally chopped off short to put it in Gb, and (ii) he was using a dual-bore slide, on which the larger bore (14.3 mm) matched that of the attachment. Allen preferred the dual-bore slide because its sound blended well in between the first trombone and the bass. But he never experienced any of the attachment problems others complained about. In fact, he told me, he used the major-third attachment alternates a lot, and rarely used positions beyond SA 4th. The second fact was that my own Olds “Recording” model (that I already had already modified to Bb/G) did not exhibit any of the usual problems. At first, I thought that these two facts had to do with the shorter attachment tubing. Then I realized that the Olds also had a dual-bore slide (again with the larger bore very closely matching that of the attachment). I immediately contacted René and relayed my suspicions that a “matched bore” might fix some of the problems. Thus began a long collaboration trying to solve this puzzle. I was fortunate enough to be able to visit him in Geneva several times on my way to or from international technical conferences in my research field of computational fluid dynamics. René began experimenting with matched-bore Bb/F tenor prototypes of various bore sizes (using his own valves, of course); and I had some prototypes built by modifying Willson tenors in two bore sizes with Rotax valves: replacing the “oversized” F-attachment tubing with smaller matched-bore G attachments. Plus, some other combinations: an Eb/C alto and a C/A tenor (cut down from my already constant-bore Olds).

The results were stunning: all of the usual “problems” immediately evapourated in all cases. Attachment alternates were the full equivalents of their slide-alone counterparts (of the same sound-path length) in terms of intonation, tone-quality and attack response; and those with longer sound-paths were very similar. One Saturday morning, when I was visiting Mr. Hagmann’s shop in Geneva, Andrea Bandini from Orchestre de la Suisse Romande strolled in to chat. René had been demonstrating to me a combination of a Bach 42 bell with standard (14.3 mm) F attachment and one of his own valves, with a lightweight Bach 50 slide—a constant 14.3 mm throughout slide, valve and attachment. He handed it to Andrea, who proceeded to run through some beautiful orchestral excerpts, especially in the low-tenor register using the valve. Andrea was extremely impressed with the uniformity of the response over all registers (even up to the sixteenth harmonic!). Until he looked at the slide and exclaimed, “Mon Dieu, c’est un coulisse de trombone basse!” And handed it back to René like a hot potato, as if this were some kind of Frankenbone. Except for the valve, this was, of course, identical to the LT42BOF developed by Bach several years later (in coordination with Jay Friedman).

As mentioned elsewhere, I published an article in the Spring 1999 issue of the ITA Journal, “Improving Attachment Intonation, Tone Quality and Attack Response”, outlining the results of our investigations. This was met with “mixed” reviews, to say the least. Apparently, it was too far out of the accepted “conventional wisdom” to be believable to some people. [Apparently, I had “stepped on some toes”. I won’t go into some of the nasty personal attacks I received at that time.] Although René and I had only studied matched-bore tenor prototypes, we speculated that something similar would apply to bass trombones, as well. And this was later confirmed by René. In fact, he was particularly concerned about the fact that on an inline dual-valve bass, his constant-bore valves (which are rather bulky) were taking up too much room along the gooseneck, where there should be a gradual expansion. This was a motivating factor for his development of his “progressive-bore” idea, which is only possible with the three-duct design of his valves. The internal ducts are (laboriously) tapered, gradually expanding in the downstream direction, effectively recreating the taper that would otherwise be in a “non-valved” gooseneck.

Of course, people will have a range of experiences with different trombones, particularly with respect to how the attachment is tuned relative to the base Bb instrument. Tuning the attachment F3 sharp can produce a better-in-tune F2—but this places the attachment C3 (and other third-harmonic notes) even further out. And may cause the C2 to be too far beyond SA 7th position to be viable. Conversely, tuning the attachment flat—so that C3 is in tune with the slide closed—probably means that the F2 is unavailable. But now the C2 is well on the slide.

In any case, getting back to the original post, in addition to choosing one of the most “open” valves available today—depending on the external dimensions desired—my advice would be to consider trying the matched-bore principle, especially if the intention is for using attachment alternates, as opposed to filling the tenor gap down to (almost) connect to pedals. In other words: use a smaller-than-conventional bore for the valve and attachment wrap, matched to that of the slide. Making sure that the construction leaves no “gaps” inside ferrules or any other inadvertent discontinuities along the sound-path. And finally (of course), I would strongly advise using the far more facile minor-third tuning for this purpose!
A
AtomicClock
Posts: 1094
Joined: Oct 19, 2023

by AtomicClock »

[quote="Sesquitone"]conn88Hagmann wrote:

...[/quote]

conn88Hagmann did not write that wall of text.
M
Matt_K
Posts: 4809
Joined: Mar 21, 2018

by Matt_K »

[quote="AtomicClock"]<QUOTE author="Sesquitone" post_id="252079" time="1725055063" user_id="15151">
conn88Hagmann wrote:

...[/quote]

conn88Hagmann did not write that wall of text.
</QUOTE>

The phpBB software doesn’t do very well with nested quotations. I just fixed it
L
LetItSlide
Posts: 152
Joined: Sep 01, 2022

by LetItSlide »

Very happy with the Hagmann valves on two Bachs.
C
conn88Hagmann
Posts: 492
Joined: Aug 09, 2018

by conn88Hagmann »

[quote="Sesquitone"]<QUOTE author="Posaunus" post_id="251991" time="1724963620" user_id="158">
In another thread, Sesquitone (Benny) makes the case that the F-attachment tubing I.D. (and valve ports) should be the same as the slide bore.

So that’s what I have on my Conn Elkhart. . . It was a kit from Hagmann in about 2009/10.[/quote]

Yes, that sounds right. René Hagmann began providing “matched-bore”
</QUOTE>

Thank you for such a thorough answer! I’m retrieving my matched bore Hagmann Conn 88 from the attic asap!!
D
Digidog
Posts: 483
Joined: Dec 13, 2018

by Digidog »

[quote="Sesquitone"]Yes, that sounds right. René Hagmann began providing “matched-bore” valve-plus-wrap kits for individuals and commercial manufacturers in the late 1990s. René and I had worked for a couple of years before that trying to discover the reason for and, if possible, to correct well-known “problems” with attachment notes. I had noticed for some time that, except for short notes in rapid passages, professional tenor trombone players using Bb/F instruments in symphony orchestras usually favoured slide-alone (SA) 6th and 7th positions for the four notes (F2, C3, E2, B2) that theoretically could have been played with the valve. When I asked some local professionals (Jim DeSano, Steve Witser, Paul Ferguson, and my colleague at The University of Akron, Ed Zadrozny) about that, I received fairly uniform “complaints” about those attachment alternates, typically: when the F attachment is tuned so that the attachment F3 matches the SA F3, with the slide closed in both cases, the second attachment harmonic, F2, tends to be flat and “stuffy” (even when the pedal is well in tune), the third harmonic (C3) tends to be very sharp and uncentered, and attack response is unreliable. Most of those players “blamed” the valves available at that time. [The Thayer valve had been invented decades earlier but was not in common use. More advanced valves such as the Willson Rotax and the Hagmann valve were just becoming available.] When I contacted Mr. Hagmann about his valve, he confirmed that he had heard similar complaints—which had been motivating factors in developing his very “open” three-internal-duct design. But even then, the problems remained. Something else was going on!

Two facts gave me an inkling as to what might be causing the “problems”. When I had spoken at length with Allen Kofsky (long-time second trombone with the Cleveland Orchestra), he pointed out a couple of unusual things about his trombone, a modified Benge 190: (i) the attachment had been literally chopped off short to put it in Gb, and (ii) he was using a dual-bore slide, on which the larger bore (14.3 mm) matched that of the attachment. Allen preferred the dual-bore slide because its sound blended well in between the first trombone and the bass. But he never experienced any of the attachment problems others complained about. In fact, he told me, he used the major-third attachment alternates a lot, and rarely used positions beyond SA 4th. The second fact was that my own Olds “Recording” model (that I already had already modified to Bb/G) did not exhibit any of the usual problems. At first, I thought that these two facts had to do with the shorter attachment tubing. Then I realized that the Olds also had a dual-bore slide (again with the larger bore very closely matching that of the attachment). I immediately contacted René and relayed my suspicions that a “matched bore” might fix some of the problems. Thus began a long collaboration trying to solve this puzzle. I was fortunate enough to be able to visit him in Geneva several times on my way to or from international technical conferences in my research field of computational fluid dynamics. René began experimenting with matched-bore Bb/F tenor prototypes of various bore sizes (using his own valves, of course); and I had some prototypes built by modifying Willson tenors in two bore sizes with Rotax valves: replacing the “oversized” F-attachment tubing with smaller matched-bore G attachments. Plus, some other combinations: an Eb/C alto and a C/A tenor (cut down from my already constant-bore Olds).

The results were stunning: all of the usual “problems” immediately evapourated in all cases. Attachment alternates were the full equivalents of their slide-alone counterparts (of the same sound-path length) in terms of intonation, tone-quality and attack response; and those with longer sound-paths were very similar. One Saturday morning, when I was visiting Mr. Hagmann’s shop in Geneva, Andrea Bandini from Orchestre de la Suisse Romande strolled in to chat. René had been demonstrating to me a combination of a Bach 42 bell with standard (14.3 mm) F attachment and one of his own valves, with a lightweight Bach 50 slide—a constant 14.3 mm throughout slide, valve and attachment. He handed it to Andrea, who proceeded to run through some beautiful orchestral excerpts, especially in the low-tenor register using the valve. Andrea was extremely impressed with the uniformity of the response over all registers (even up to the sixteenth harmonic!). Until he looked at the slide and exclaimed, “Mon Dieu, c’est un coulisse de trombone basse!” And handed it back to René like a hot potato, as if this were some kind of Frankenbone. Except for the valve, this was, of course, identical to the LT42BOF developed by Bach several years later (in coordination with Jay Friedman).

As mentioned elsewhere, I published an article in the Spring 1999 issue of the ITA Journal, “Improving Attachment Intonation, Tone Quality and Attack Response”, outlining the results of our investigations. This was met with “mixed” reviews, to say the least. Apparently, it was too far out of the accepted “conventional wisdom” to be believable to some people. [Apparently, I had “stepped on some toes”. I won’t go into some of the nasty personal attacks I received at that time.] Although René and I had only studied matched-bore tenor prototypes, we speculated that something similar would apply to bass trombones, as well. And this was later confirmed by René. In fact, he was particularly concerned about the fact that on an inline dual-valve bass, his constant-bore valves (which are rather bulky) were taking up too much room along the gooseneck, where there should be a gradual expansion. This was a motivating factor for his development of his “progressive-bore” idea, which is only possible with the three-duct design of his valves. The internal ducts are (laboriously) tapered, gradually expanding in the downstream direction, effectively recreating the taper that would otherwise be in a “non-valved” gooseneck.

Of course, people will have a range of experiences with different trombones, particularly with respect to how the attachment is tuned relative to the base Bb instrument. Tuning the attachment F3 sharp can produce a better-in-tune F2—but this places the attachment C3 (and other third-harmonic notes) even further out. And may cause the C2 to be too far beyond SA 7th position to be viable. Conversely, tuning the attachment flat—so that C3 is in tune with the slide closed—probably means that the F2 is unavailable. But now the C2 is well on the slide.

In any case, getting back to the original post, in addition to choosing one of the most “open” valves available today—depending on the external dimensions desired—my advice would be to consider trying the matched-bore principle, especially if the intention is for using attachment alternates, as opposed to filling the tenor gap down to (almost) connect to pedals. In other words: use a smaller-than-conventional bore for the valve and attachment wrap, matched to that of the slide. Making sure that the construction leaves no “gaps” inside ferrules or any other inadvertent discontinuities along the sound-path. And finally (of course), I would strongly advise using the far more facile minor-third tuning for this purpose![/quote]

[quote="conn88Hagmann"]But what you have said, actually means that it doesn’t matter what size the pipes are, matching or not. It’s just how it plays. . Which is fine of course but means no scientific theory at all can be applied. <EMOJI seq="1f937-1f3fb-2642" tseq="1f937-1f3fb-200d-2642-fe0f">🤷🏻‍♂️</EMOJI>[/quote]

What I am saying, is that flow is a practical result of testing, wheras the science behind it is a guide to what is purposeful and reasonable to try.

There are so many factors determining the flow and/or resonance in complex systems, that it can be impossible to draw any conclusions of what affects what, and that there - especially - are no standard recepies for making a pre determined impact on them. You can calculate to a certain degree, but for the most part you have to test and when you get the desired results compute backwards to see what has been achieved.

The theory of matching pipe diameters, is only valid in a specific practice of how you assemble certain pipes. There is no scientific evidence or theory that says that it would be a universal solution to any assembly of other pipings, valves or flares. For all science says, it could well be very wise to make the piping insides rough like sharkskin, to facilitate passage of air and increase flow, and that it could be very wise to have valves with significantly larger diameter than the ensuing pipe to increase flow at a point where flow is expected to change when the valve moves.

Note the word "could" here, because science only says what in closed and defined systems, in singular conditions, makes for an effect on the flow, not what combinations of situations and conditions are best practice - because then too many factors with each too large impact works in combination to make the combined system impossible to compute without first testing it.

What @Sesquitone says is that Hagmann did a lot of testing and found a practice that works for the assemblies that the Hagmann workshop does, with the components they use and apply. There is absolutely nothing of the results of that testing that can be applied to the components used by other builders - or probably even the materials used. Everything has to be tested. Change one fraction of a grade to the inclination of the inner diameter of a Hagmann valve, and everything could be upset in a totally unexpected way - forcing the whole process of testing and trying to start anew.

So no: Flow and resonance are not a one-recepie-fits-all. Science clearly says it's much, much more complex and complicated than that.
I
imsevimse
Posts: 1765
Joined: Apr 29, 2018

by imsevimse »

I'm happy with all the horns with attachments I have. Most are old of the brands Conn, Bach, King, Yamaha, Benge, Kanstul, Holton, Schilke, Martin, Edwards, Olds, Selmer and Thomann.

I have only one with thayers and that's an Edwards 350. It's nice. I've also tried several basses with thayers and didn't like them much. I think it's because I'm not used to play that valve. For me they are too open so they suck my air, and I'm not a large person so I need that air. It is more of a problem in the valve register so the thayer on my Edwards 350 isn't much of a problem because there are not many long low notes I need to play in it's low register. The many thayer-basses I tried were all old conn horns converted to thayers and I just felt the original conn character was lost on all of them. I've also tried an inline Shires bass with thayers who belongs to my friend. If I played the thayers with more resistance on my lips they started to work and then they in fact needed less air but I sounded like a tuba and that's not my cup of tea. I guess it needs more time to learn than just a couple of minutes. I guess that more teutonic character is probably what I need to embrace if I want to learn to play that valve. I guess in time I could learn also to color the sound more. I think my problem coming from a comfortable world of old rotors is the opposite from those who come from a not comfortable world of old valves that are stuffy. From where I come, the old ways, I need to increase resistance in my lips to be able to play the thayer and they who come from the opposite place need to instead decrease the resistence in the lips to play the old rotors. It's as I see it two different ways of getting the resistence we all need to be able to make a sound. It might be possible to be comfortable in both techniques. Hagmanns is something in between so that's where we can meet. This is my theory. It's not that easy to change after many years of playing old rotors. If I ever consider another bass I might choose a double thayer just to explore if I can learn to play that valve with a sound I like. I know some probably like to think of the bass sound they want as "a big teutonic sound" or "a modern bass sound" or "a modern symphonic classical bass sound" as opposite to how I like to describe the sound I want; "a sound that projects like hell" or " a commercial sound" or "more lyric bass sound". I like many different sounds. Any sound that fits the context. Some very skilled players could probably cover any sound just imagening that sound on any valve-type they choose, but my belief is they probably are more comfortable on one of the valve-types, and that depends on where they come from. I think it's time for me to visit the few shops we have here and spend some time on a thayer-bass.

/Tom
A
although
Posts: 72
Joined: Feb 13, 2019

by although »

I feel like other instruments don't have this fascination with finding the perfect valve... I don't haunt the tuba/trumpet/euphonium forums, so maybe I'm just not seeing it. Still, I sometimes think that we get way too wrapped up in the grail quest. Best valve is no valve.
P
Posaunus
Posts: 5018
Joined: Mar 23, 2018

by Posaunus »

[quote="Sesquitone"]<QUOTE author="Posaunus" post_id="251991" time="1724963620" user_id="158">
In another thread, Sesquitone (Benny) makes the case that the F-attachment tubing I.D. (and valve ports) should be the same as the slide bore.[/quote]
</QUOTE>
Question for Sesquitone:

Benny:

What is the typical Reynolds number (probably rather low) through the slide / valve / attachment tubing?

How does that affect things?
B
brassmedic
Posts: 1447
Joined: Dec 14, 2018

by brassmedic » (edited 2024-09-01 9:24 p.m.)

[quote="although"]I feel like other instruments don't have this fascination with finding the perfect valve... I don't haunt the tuba/trumpet/euphonium forums, so maybe I'm just not seeing it. Still, I sometimes think that we get way too wrapped up in the grail quest. Best valve is no valve.[/quote]
But that says it all right there: "Best valve is no valve". The holy grail is a valve that plays like it's not a valve. The reason the other brass instruments aren't looking for that is they are accustomed to playing every note through the valves. That's what they do. A valved trumpet does not sound like a natural trumpet, and a valved french horn does not sound like a natural horn. To them, that is a feature, not a flaw. And tubas have always had valves. They like the sound that they get. The trombone is unique in that it is essentially the same design as it was in the 16th century. That's the sound we want to hear, and a valve trombone does not have that sound. So trombone players look for a valve that will preserve that tone quality yet still give us added range and facility.

Zig Kanstul built a french horn with CR valves, hoping to offer this "improvement" to horn players. A horn player who tried it didn't like it at all. He was used to using the resistance of the traditional rotary valves to help connect the notes in a phrase. He liked the resistance. Horn players have no interest in more open valves. I suspect trumpet and tuba players wouldn't either.
H
hornbuilder
Posts: 1384
Joined: May 02, 2018

by hornbuilder »

I agree with Brad.

I had a great discussion with Ed Thayer at one point. He was wanting to make a French horn with axial valves. He intended for the player to have the right hand outside the bell to correct into action by manipulating a tuning slide. I suggested that the valve resistance, or lack of with e axial design, would not be a positive for the player. But the real kicker would be not having the hand in the bell to adjust intonation. So sorry horn players. You didn't get axial valves because of me!!
S
Sesquitone
Posts: 291
Joined: Apr 25, 2022

by Sesquitone »

[quote="Posaunus"]

Question for Sesquitone:

Benny:

What is the typical Reynolds number (probably rather low) through the slide / valve / attachment tubing?

How does that affect things?[/quote]

For steady flow of air through pipes, brass instruments are way down at the bottom/left-hand corner of the Moody diagram: laminar flow, small relative roughness. Therefore, the friction factor is going to be quite low. Very little "resistance" (end-to-end pressure drop), even with a valve or two along the way. Unless you have a valve half-cocked, for example, which changes things to "orifice flow". Then you can sometimes "feel" (and hear) some resistance. Especially if the valve is not well vented (thereby blocking the flow when half-cocked), in which case you get a lot of resistance, pressure build-up, and a "pop" when the valve is re-seated and the pressure relieved. An "ideal" valve should be so well vented (allowing laminar flow around the outsides of the active sound-path ducts during transition) that there is no hint of orifice flow (and therefore not the slightest sign of popping) when switching between the two active orientations.

.
B
BGuttman
Posts: 7368
Joined: Mar 22, 2018

by BGuttman »

Remember that the density of air is very small, the viscosity of air is near zero, and the exhalation flow rate of air is very small. I think if you calculate the Reynolds number for breath air flow through a tube approximately 13 mm in diameter you will find it to be 100 or less. This is below the left hand axis of your chart. In the scale of most engineering calculations of air in ducts or liquid in pipes our brass instrument flows are below any normal consideration.
S
Sesquitone
Posts: 291
Joined: Apr 25, 2022

by Sesquitone »

[quote="BGuttman"]Remember that the density of air is very small, the viscosity of air is near zero, and the exhalation flow rate of air is very small. I think if you calculate the Reynolds number for breath air flow through a tube approximately 13 mm in diameter you will find it to be 100 or less. This is below the left hand axis of your chart. In the scale of most engineering calculations of air in ducts or liquid in pipes our brass instrument flows are below any normal consideration.[/quote]

Yes, that's entirely correct. I should have shown an arrow pointing off the logarithmic scale across the left-hand border of the Moody diagram. Reynolds number in a pipe of circular cross section is defined as: fluid velocity (V) times pipe diameter (D), divided by the kinematic viscosity (nu) of the fluid, which, for air, is quite small at 1.5 x 10^-5 square metres per second. Plug in some numbers for a brass instrument, and, even with that small value of nu in the denominator, Re is well into the "laminar" region. Relative roughness is also very small for the type of surfaces found inside brass instruments. All of which means that, unless there is some kind of other constriction within the sound-path, the resistance to air-flow is almost negligible. However, acoustic impedance (matching sound waves from one end of the instrument to the other) is entirely unrelated to flow resistance or the volumetric rate of air-flow. Experiments have been done where there is a "membrane" across the bottom of the cup of the mouthpiece blocking air flow through the instrument (with a hole in the side of the mouthpiece to allow the air to escape)—but allowing sound-waves to propagate (and reflect back-and-forth), as usual. As I recall, the impedance spectra over a wide range of frequencies were essentially the same as with a normal mouthpiece (of the same shape). Perhaps someone can find a link to that study.
B
brassmedic
Posts: 1447
Joined: Dec 14, 2018

by brassmedic »

When people talk about matching the valve tubing to the inner slide bore, I don't think they consider what happens when you use the outer positions on the slide. On a .547 bore instrument, the inner diameter of the outer slide is around .585. If you play a note in 6th position, you are introducing a section of tubing that is much bigger in diameter than the valve tubing (normally .562). If you have an instrument with .547 valve tubing, a note played in first with the valve is going to be a lot stuffier than a note played in sixth without the valve. I think that's why makers have gravitated toward the .562 bore valve section - it blows more like the open horn.
H
hornbuilder
Posts: 1384
Joined: May 02, 2018

by hornbuilder »

Thank you Brad.

My sentiments exactly, and experience in actual play testing many different prototypes with varying bore combinations. There is a very valid reason why there is a "standard"!!
D
Digidog
Posts: 483
Joined: Dec 13, 2018

by Digidog »

From all I know of flow theory, I call most of the statistical compilations for B.S.

Again: There are no theoretical calculations you can make to ascertain and guarantee certain desired traits of flow and resonance; you can calculate what is meaningful and purposeful to try and test, but no certain way of predetermining an outcome solely from a theoretical basis.

What most calculations miss are first turbulence - and the positive effect it can have on flow and resonance - and, second, changes in viscosity of the medium of the flow. A horn that plays really well in 20C or 68F, can be a disaster in 35C or 95F [EDIT] I once had a horn that changed like this, but not so drastically. [/EDIT] due to the changed viscosity of the air - which can depend on anything from the temperature itself or changes in humidity, or changes in particle contamination due to changed conditions, or simply the slight material expansion of the horn from increased temperatures.

As I said before, it could well make for a drastic increase in flow and resonance in a horn from making the tubing insides of - f.ex. - the bell roguh with microscopic knobs to create turbulence along the tube walls that aids an increased passage of air (and increase the speed from any given energy of the passing air) and makes resonance better in combinatin with a slight but dispersed increase in weight and its (regular or irregular, depending on) distribution.

From my own experience, I have seen flow increase from seemingly horribly mismatched pipes, where in one case turbulence from a sudden expansion in diameter actually increased the draining of an earlier placed long bend to the sewer pump in the plumbing of my summer house.
J
jonathanharker
Posts: 139
Joined: Aug 14, 2022

by jonathanharker »

Campbell, Murray; Gilbert, Joël; Myers, Arnold (2021). [url=https://search.worldcat.org/title/1163945289]The Science of Brass Instruments. Cham: ASA Press. ISBN 978-3-030-55684-6

I've found this book to be very interesting for these sorts of discussions. In particular, section 4 goes into the acoustics, resonances, flow characteristics and sound radiation (bell flare, the "Horn function"); section 6 looks at non-linear propagation, acoustic pressure waves, Burgers Equations, and what happens and why things change when we play fortissimo (sawtooth waves!). Well worth a read if this sort of thing appeals.
J
jonathanharker
Posts: 139
Joined: Aug 14, 2022

by jonathanharker »

[quote="Digidog"]The CL2000 is a great valve [ ... ] I concur with Harrison, though, that there are some issues.

First: is it still in production, so spare parts or complete valves can be found? Or do one have to have a tech build parts from scratch if something like the rotor or a pin has to be switched? I have tried to purchase a complete valve for my Yamaha 421 through both the European and the Swedish Conn agencies (the 421's valve is worn and in need of replacing), but without any response at all from Conn. I don't see new horns from Conn equipped with the valve either, so it makes me wonder whether the valve is out of production or not.

[ ... ]

Over all, I think that the principles and the functions of the CL2000 are great. Had I been able to buy a valve from Conn for my 421, it had been my absolutely preferred choice, but now I'm planning to refit the horn with a Meinlschmidt valve. Then I have to see how the valves on my Conn 62 age, but this far everything has been fine and well, and if the build quality hasn't deteriorated catastrophically and if the valve still is in production, I'd wholeheartedly recommend it; both for a bass or a tenor horn.[/quote]

The CL2000 valve patent expired in 2018, so (in theory at least) anyone ought to be able to build one.

From the above discussion about airflow and tiny Reynolds number, might that be why the unused "appendix" in the Y-shaped rotor inlet port might not matter as much as we think it should?

User image
S
Sesquitone
Posts: 291
Joined: Apr 25, 2022

by Sesquitone »

[quote="jonathanharker"]

The CL2000 valve patent expired in 2018, so (in theory at least) anyone ought to be able to build one.

From the above discussion about airflow and tiny Reynolds number, might that be why the unused "appendix" in the Y-shaped rotor inlet port might not matter as much as we think it should?

User image[/quote]

I'm always a bit leery about inadvertent "chambers" along the sound-path. René Hagmann tells the story of a Bach 42B with one of the earliest of his valves on it. One of the attachment notes was an unplayable wolf tone. After a lot of investigation (for leaks and so on), when he inspected the inside of the slide receiver, he found a large gap between the end of the slide and the beginning of the inlet knuckle of the valve, thereby causing a small oversized-bore "chamber". When he filled this with a small sleeve, creating a constant-diameter gap-free pathway throughout the receiver, the problem disappeared completely. Apparently, the "chamber" was acting as a little Helmholtz resonator, with its own (high) natural frequency. This may have been enough to interfere with the overtones of the problem note thereby causing the wolf tone. Mr Hagmann has routinely filled such gaps with constant-diameter sleeves ever since. This inadvertent gap seems to continue to be a problem with Bach instruments. Avoiding it is the main reason for the (thumb-screw-tightened) non-tapered butt-joint on Rath trombones. This is not a "tuning slide"!

As is well known, there is a whole "subculture" surrounding "The Gap" between the end of a trumpet mouthpiece shank and the beginning of the lead-pipe, with "camps" on many sides regarding how long this should be (if at all).

However, in the case of the CL valve, similar problems do not seem to have been reported.

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conn88Hagmann
Posts: 492
Joined: Aug 09, 2018

by conn88Hagmann »

So I’ve gone back to my Hagmann Elkhart, with 547 bore plug. using it along side a Greenhoe Conn from about 2006 with 562.

The Hagmann feels the same in plug and open. The Greenhoe still has that “thing” they do. But Less so than on a standard valve . . .
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hornbuilder
Posts: 1384
Joined: May 02, 2018

by hornbuilder »

That is not a viable comparison. Different horns, different valve type.

I've done the experiment where I made 2 valve sections, using the same valve type. One was .547" bore with . 547" tubing. The other was .562" bore with .562" tubing. Same bell, tuning slide and handslide. I know what I think works better!!

Hagman valves do not play the same open vs activated. In my experience the valve side feels more "open" than the straight horn, and loses focus and core.

I'm curious about your comment of "that "thing" they do". What thing? Be specific, or your comment is useless.
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hornbuilder
Posts: 1384
Joined: May 02, 2018

by hornbuilder »

BTW. Hagmann do not use decimal/inch tubing size. They use metric mm tubing. Tenor valve section tubing is 14mm, which is .551". Bass is 15mm, which is .590".
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LeTromboniste
Posts: 1634
Joined: Apr 11, 2018

by LeTromboniste »

[quote="hornbuilder"]BTW. Hagmann do not use decimal/inch tubing size. They use metric mm tubing. Tenor valve section tubing is 14mm, which is .551". Bass is 15mm, which is .590".[/quote]

Interestingly, their default conversion kit for a Bach 42 (or at least it was when I got mine) has a 13.8mm (i.e. .543") bore Bb duct inside the valve (the F ducts match the F wrap with a 14.0mm bore)

You can also get it with 14.2mm (.559") ducts, ports and wrap, but that's not what they recommended for my 42.
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LetItSlide
Posts: 152
Joined: Sep 01, 2022

by LetItSlide »

[quote="BGuttman"]Remember that the density of air is very small, the viscosity of air is near zero, and the exhalation flow rate of air is very small. I think if you calculate the Reynolds number for breath air flow through a tube approximately 13 mm in diameter you will find it to be 100 or less. This is below the left hand axis of your chart. In the scale of most engineering calculations of air in ducts or liquid in pipes our brass instrument flows are below any normal consideration.[/quote]
Thought-provoking post, there.

For us brass players, our horns are amplifiers for our vibrating lips. Of course, a horn is more than just an amplifier. It has mechanisms for controlling pitch, too. Anyway, we direct our airstreams in specific ways to get the sounds we want, but we aren't blasting air through our horns like water through firehoses. It's more about getting the amplifier to vibrate in the right way.

Many different valve designs work well. We learn the feel of the ones we happen to have in our horns, along with everything else about each horn's geometry & materials, and figure out how to get our best sound with each setup.