The MAW valve

[bububassboner]

http://www.jm-gmbh.de/html/e_meinlschmi ... _valv.html" target="_blank

Does anyone have any info or real life experience with these valves? Looks like a good way to cut down on weight and friction of the valve. Looking for any thoughts on these valves.

[T. J. Ricer]

Match them up with these and you'll be well on your way to light pistons: viewtopic.php?f=9&t=52568" target="_blank

--T. J.

[joh_tuba]

Those valve buttons are a cool idea, however...

The density of stainless steel is very similar to brass.

If the goal is to reduce weight titanium would be half the weight and nylon would be 1/6th the weight(also possibly quieter?)

There are also very affordable machinable super lightweight aluminum ceramics that would work very well in that application.

[joh_tuba]

Back on topic...

The MAW valve is designed by Martin Wilk.

His website: http://www.mawvalve.com/" target="_blank
The patent: http://www.google.com/patents/US8227677" target="_blank

Looks like he has an interesting rotor design as well.

I exchanged a few emails with Martin about his design and he encouraged me to call him to discuss it in more detail but I've not yet followed up on that.

I have also chatted with a couple folks that have played them.

From what I have gathered they are the STANDARD MW piston valve that are modified and then nickel plated.

Those that have played them are people I respect. They have only said positive things. I'm inclined to believe them.

[Frank Ortega]

My Martin 4/4 has a replacement set of MAW valves. They are modified king valves that were made before these production ones came out. They are fantastic. An incredible response and very big tone. Makes the 4/4 sound more like a 6/4. I highly recommend them. I even tried another set on my old Thor and I could still hear and feel a big difference. These are a real innovation!

Frank Ortega

[keegan watson]

I've played a couple of tubas that have these types of valves. These tubas were sent to Martin for the valve job and to have him "tweak" the horns. Both of these particular tubas (A 56J and Pt-606p) played great. The valves really open the horn up and allow for the horn to play bigger than before the valves. The response on both of those horns was very good, they were each very easy to play.

[joh_tuba]

He describes it in that patent link. Click "read this patent", click 'drawings' and scroll to page 7 and 8 to get an understanding of it.

He describes a MAW rotor design and a method for modifying a Rotax valve. The MAW rotor design is similar to a normal rotor BUT one side is a perfectly round tubular circle that crosses PAST the center-line of the rotor(unclear how you would machine that out of solid brass maybe it would need to be built like a piston?). The other half is 'squished'. The 'squished' side is engaged when the rotor is closed. The 'open' side only comes into play when the rotor is engaged. Presumably the response would remain more constant when multiple valves are engaged.

To Bloke: You don't need my approval. They look nice and based on your criteria stainless steel makes sense.

[rodmathews]

I have a set of these valves coming to the San Francisco Bay area if anyone wants to try them. I will be trying them with my B&S PT-6P, and I am really looking forward to seeing how they perform. The idea really makes a lot of sense.

[tubalex]

I know Martin well and he still does all the significant work on my tubas when I am in the Midwest in the summers. That's right, I go from Flagstaff, AZ to his shop in a tiny town in southern Indiana to have the important work done; he's that good.

This summer I got together with some players at ITEC, some orchestra pros, some college teachers, all in a higher income bracket than myself, and we compared some C and F tubas, and also compared sets of piston valves, including the MAW valves. This was in the Brucknerhall basement, away from the elephant room. The MAW were definitely the winners among the piston valves. I must say the combination of the MAW valves with the B&S MRP piston-valve F tuba was just stunning. That's not just me talking-the group of us found that to be the superior combination that day.

I've been watching Martin develop these valves and wait for the patents for years. This is a real advance in design by a remarkable technician.

[Lee Stofer]

As for the original post, I think that the primary difference these valves would offer is less airway restriction, in effect opening-up the instrument. There would not be a significant reduction of weight or friction. The best reduction of friction is to have the pistons and casings that fit each other well, are really clean, really smooth, and well-lubricated. As for weight reduction, some of the lightest-weight valves I have ever played were made in the 1920's and 1930's, pistons made of thin-wall nickel-silver that were nickel-plated and then hand-lapped and fitted in Conn, Buescher and York tubas. I think that Kanstul has the fastest, smoothest tuba pistons available in a new instrument.

The stainless steel finger buttons are quite interesting, as well. The mother-of-pearl disc used in a traditional finger button is really pretty lightweight, but some of the brass finger buttons that have been made have been unnecessarily heavy. York did a great job in this respect, too, making large finger buttons that were both lightweight and comfortable.

[Rick Denney]

If the goal is to reduce weight titanium would be half the weight and nylon would be 1/6th the weight(also possibly quieter?)

Titanium is half the density of steel and can be alloyed and treated to be just as strong, not that strength is important. But titanium alloys are expensive and commercially pure titanium is a screaming bitch to machine without galling and form without cracking. It's also subject to fatique without being alloyed with aluminum and (particuarly) vanadium.

The problem with polymers is that the coefficient of thermal expansion is much greater than any of the metals used in tubas. Hirsbrunner made rotors once upon a time with a polymer core and a metal sleeve that had a tendency to lock up in hot weather.

So, the trick is to 1.) avoid the galvanic corrosion that can result from dissimilar metals, 2.) use a material that can be applied reasonably without driving up the costs unnecessarily, 3.) has a coefficient of thermal expansion similar to the material used for the casing (as constrained by the structure of the instrument).

As Lee says, there should be nearly no friction if the valves are kept lubricated. The valve should float on a film of oil, and all the friction should be between the oil molecules, not between two hard surfaces.

Light weight counts, I suppose, though I never cease to be amazed by how stiff some people seem to want their springs.

If Pat Sheridan can play the stuff he plays on Besson extra-long compensating valves, then I have this feeling that valve mass is not a real limitation on playing.

Rick "whose valves are faster than his fingers" Denney

[ralphbsz]

To make sure I 100% understand the discussion so far:

• These new MAW valves are considered to be the bee's knees, for logical reasons (no bumps in the air passage in the valve, the air passage has a circular cross section everywhere).
• They replace the piston in piston valves.
• Martin Wilk, the inventor of these valves, also describes replacement rotors for rotary valve instruments in his patent, following the same general idea.
• But the rotor valve models are not available (yet).
• Rod Mathews (who lives less than 1/2 hour from us) has a set of MAW piston valves coming in, and is willing to graciously let other people try them out.

Did I get it more or less right? My son plays on a MW 25 rotary tuba, so new pistons won't help him any. Clearly, at this point the speed and air flow of his valves are not the limiting factor in his playing, his skills are. He needs to practice more, and study for another few years, before he can utilize super-duper valves. But looking at what I wrote above, it's quite possible that in a few years, rotors with circular air passages (no bumps, no distortion) will be easily available. I see a Christmas present for him, in 2 or 3 years time.

[Alex C]

People should realize that new pistons are not plug-and-play. They will have to be lapped to fit the casings of the individual valves. A repair tech who knows what he's doing will have to oversee this aspect of the installation.

[DavidK]

Martin gave me permission to spill the beans on his valve update, now that the US Patent is secured.

Look up "maw," as in gaping mouth. That is the kernel of this update.
A large open channel has replaced one of the cross-tubes in each piston. Dramatically lowering the air resistance. MAW also happen to be Martin's initials, so we both had a chuckle over that.

The pistons work, exceedingly well.
No other voodoo or black magic.

This evening I took delivery of my second MAW-valved tuba. A 2004 BBb King 2341. The playing characteristics are noticably improved. Very free blowing and open sounding. I can play chromatically down to pedal GG below pedal BBb. At fortissimo! You can really open up and wail. You are not limited by the typical "care in feeding" of air as is usually required for playing the narrow bore Kings in the low register. This horn does not "back up" on you in the lower register. This horn had very good intonation to begin with, and the piston update did not have any adverse effect on intonation.
Does a 4/4 King play like a 6/4 Holton? No, because I have one of those and can vouch for the difference. But the King does play "bigger" and sounds great. It does not feel like you are playing a 4/4 tuba. I am a very happy customer!

I took delivery of my other MAW-valved horn about 18 months ago. As a proof of concept instrument from Martin Wilk. It is a 1915 Conn Donatelli-sized chassis with a MW large piston 4 valve set installed. I was able to take detailed measurements of "The" Conn Donnatelli when it was at Dillons a couple years ago and mine has identical measurements. The only difference is that it does not have "Donatelli" engraved on the bell. Instead, it has U.S.N. engraved in a factory-original scroll for this type of military designation. (Very cool!) Mine started life as a U.S. Navy BBb top action tuba. Martin did all of the custom plumbing to get the MW set to fit where I desired and have the top tuning slides accessible by reaching through the top bow, instead of over. And it has one of his early Patent Pending MAW valve sets, making it very unique.

The Conn plays flat-out huge for a 5/4 tuba. As big as I will ever need. Apologies to my Holton 345. Free blowing. Huge voice. Still in BBb and no need for a 5th valve. Just plain fun to play! I am still a very happy customer!

Hope this info is helpful.

[DavidK]

As for lightweight finger buttons....
Titanium is interesting, but expensive.

Back in 2005, I filed and sanded my King buttons flat and then rounded the edge slightly, because I did not like the concave feel and how it aligned with my fingers. Martin turned a nice 1/4 round on the top edge of the buttons. They look great and feel fantastic!

Comfort achieved! Weight reduction? A happy bonus.

[DavidK]

Day 2 with the MAW-valved King 2341 and enjoying the daylights out of it! I have a feeling that my tuba cohort from Bergen county will be wanting to schedule an A/B session some time soon with his MAW-valved horn.

The lighter weight piston concept will certainly make for a faster moving or "lighter" action. It is simple physics. So Joe's logic is sound. And the SS buttons look very nice!

Martin and I discussed the possibility of change in piston weight, but we never took a "before" measurement. We agreed that it probably wasn't significant in the case of my update. But.... for the sake of discussion, I would wager that the current King 2341 valves are made to the same specs as they were in 2004. So a side by side comparison would be pretty accurate in my opinion. Just have to get my horn and an unaltered King 2341 or Conn 5xJ AND a precision scale in the same place at the same time. (your milage may vary)

Joe, When the circumstances permit, I think you will enjoy your A/B testing with Martin. And I bet you'll have some lively discussions!

[rodmathews]

ralphbsz - yes, I think you have your summary right. I'll let you know when I get these.

bloke - these are interchangeable. I had the same concerns about modifying my existing valves. I want to do an A/B test and see what effect they have.

I'm looking forward to getting the MAW valves to try AND the lightweight finger buttons, which I'll use on either my existing valves or the new ones if I go that way. The mother of pearl is chipping out of my original finger buttons, so those are a done deal. I also got some lighter weight springs from bloke, and I'm optimistic that my hand won't get as tired with the new spring/button setup.

[iiipopes]

OK, I've seen various valve systems over the years that promote playability.

Every one of these is forgetting something: it's nice to have as open a blow as possible through the valves, but by the nature of the cylindrical tubing, when a valve is pressed, it will be a harder blow than if the valve is open.

Have any valve systems actually taken this into account: that it is the consistency of the blow, from open through whatever valve combination, that helps a player be consistent in tone, intonation and pitch? It's not the absolute resistance to the blow, but the relative resistance to the blow that provides the feedback to the player.

In other words, I've actually been known to add resistance to the open port of the 3rd or 4th valve to tighten up the open blow so when I push 3 or 4 that there is not a noticable difference in the blow, which keeps air flow or relative resistance consistent, and therefore more consistent articulation, slurring, pitch centering, etc.

So this is an interesting system, but give me a valve system that regulates the resistance to be equal whether or not the valve is pushed, so that the path through the valves when depressed is the more "open" path through the valve, and the open valve path is offset to maintain a similar resistance for more consistency of blow.

[Frank Ortega]

Actually, however it is accomplished, I do believe that the MAW valve gives the most consistant blow when valves are depressed or open. Slurring is easier, response is quicker, and tone is just plain bigger.

Obviously I'm a fan. You'll have to try them for yourself.

Frank

[jtuba]

Call him, he will call you back and answer all of your questions. I didn't find it particularly cheap, but won't know the true value to me until I'm able to A/B and record for myself.