Alan Baer's PVAK...

[bill]

I have PVAK installed on my Willson 3400. I concur with the assessment written here. The immediate effect was quite amazing. Even more startling was the lasting effect. The horn characteristics do not change after the first couple of weeks or months you play. The installation ( always a concern for me since I can really foul up mechanical things) was very easy and Alan Baer sent a picture, with instructions, with the kit. The horn is easier to play, faster responding and clearer in tone. In other words, it plays as it did when I got it and as it did for the first two weeks after the last cleaning, a year before. These characteristics have not changed, at all, since the installation.

[Steve Marcus]

Alan Baer writes on his website about PVAK:

It is my theory that this [the o-ring] frees the weight of the piston from the rest of the instrument. This is very much like the phenominum that we experience when we use a stand for the tuba. The tuba is a vibrating body and the stand creates a limited amount of contact to the tuba, thus allowing it to vibrate more freely. Freedom to vibrate will result in more resonance! The o-rings act as a separation device or "stand" for the piston, so the rest of the horn can vibrate without the excess mass of the pistons.

Is that to say that the PVAK is ineffective or rendered superfluous if you continue to hold the horn in your lap rather than use a stand (analogous to implementing a rigorous exercise regimen while dining on fast food three times a day...)?

Alan also lists specific models for which the PVAK is available. What about tubas not on that list that had limited production in specific configurations? Would Alan have to custom fit a PVAK himself and, if so, would the standard price of $180 prevail?

[imperialbari]

Alan Baer writes on his website about PVAK:

It is my theory that this [the o-ring] frees the weight of the piston from the rest of the instrument. This is very much like the phenominum that we experience when we use a stand for the tuba. The tuba is a vibrating body and the stand creates a limited amount of contact to the tuba, thus allowing it to vibrate more freely. Freedom to vibrate will result in more resonance! The o-rings act as a separation device or "stand" for the piston, so the rest of the horn can vibrate without the excess mass of the pistons.

Is that to say that the PVAK is ineffective or rendered superfluous if you continue to hold the horn in your lap rather than use a stand (analogous to implementing a rigorous exercise regimen while dining on fast food three times a day...)?

Alan also lists specific models for which the PVAK is available. What about tubas not on that list that had limited production in specific configurations? Would Alan have to custom fit a PVAK himself and, if so, would the standard price of $180 prevail?

Steve, you sound like you have some experiences from inside the music industry. Is it so?

Klaus

[Steve Marcus]

Klaus, although I work in the music industry, that is irrelevant to this topic. I'm sincerely curious about the PVAK for my Nirschl 4/4 CC tuba and my questions are genuine.

[imperialbari]

Any hands-on precision alignment done by a competent repairman shall ensure the optimum of free-blowing and of response in any given piston brass instrument (rotary valve alignment is not a topic here).

Whether one will choose the potentially more durable, but also more noisy and heavy, option of metal combined with O-rings over the most stable versions of felt rings (really synthetic foam) is the choice of each player. The so-called synthetic felts will compress very slightly, but will return to their original shape very fast. They can achieve the exact same degree of alignment as the former solution, if they are combined with thin plastic shims. They may have a shorter life-span that the Brass & O-ring solution, but they will last longer than conventional felts.

The Baer solution assumes, that all tubas of the same model may be aligned precisely by means of identical sets of PVAK’s. At least one very competent repairman says, that even the finest and most costly models have deviations in their alignment needs from instrument to instrument. If that is true, uniform sets of PVAK’s do not obtain their goal at a uniform level justifying an exorbitant price level.

I become very worried, when I read this on the Baer site:

“Another advantage of using the o-ring instead of a wide rubber washer or felt is the lack of contact that the piston now has against the top of the valve cap. The contact patch of the o-ring is approximately .070. It is my theory that this frees the weight of the piston from the rest of the instrument.”

The physical model of an engaged piston is very complex, as the piston is held by a set of forces:

the finger of the player - the finger is connected to the instrument body via the hand, arm, and probably more parts of the player’s body

the force of the finger is countered by the spring, which is sitting more or less compressed in the bottom of the piston casing held in place by the bottom cap

there is a lateral contact to the wall of the casing via the valve guide and via the film provided by the lubrication.

The physical model of the un-engaged piston is simpler, as it is pressed against the top cap by the force of the spring. That contact force is the exact same independent of the contact area being small as with the O-ring or via the larger contact area of the synthetic felt ring. In the former case there is a higher PSI distributed on a smaller area, in the latter case there is a lower PSI distributed over a larger area. The contact force is determined alone by the tension of the spring and by the gravity influence on the piston. There is no way, that the weight of an un-engaged piston can be removed from the combined resonance body of the whole tuba.

I do not dispute the potentials of good resonance from the Baer solution. However they do not come from the quoted advantage theory, but from the precision of the alignment.

The quote reveals a lack of understanding of physical models or it is an expression of voodoo marketing. Neither is trustworthy in a marketing based of the assumed confidence in the holder of one of the most prestigious and well paid tuba chairs in the world.

Mr. Baer has PM’ed me. I was allowed to quote the PM on TubeNet, which I will not do. I was asked to contact Mr. Baer in private. I cannot see any point in doing so. The Baer-marketing machine runs in the open. Hence it has to accept that my criticism of it and of its cult-like nature happens in the open as well.

To those in doubt about what to do about the alignment of their valves my advice will be:

If you prefer the Brass & O-ring solution, then go to Mr. Baer or to another competent repairman and ask for an individual and specific alignment of your instrument.

If you prefer a different solution, then go where you will find it. As hinted earlier in another post my solution would be to buy several synthetic felts and plastic shims. I might even punch some of the shims myself. And then I might invest in an endoscope and still come out on top, but then I have 200 valves to attend to in my collection.

I have discussed this whole matter in private with some of my reference persons, but it is my own knowledge of physics and my history as a consumer politician, that have determined my standing on this matter. Knowledge gives obligations. So does the possession of a big name.

Klaus Smedegaard Bjerre (who never studied technical English, but studied some technical matters in English)

[MikeMason]

As one of the first to jump on the bandwagon after the initial public offering,no regrets.My Thor is happy which makes me happy which makes those around me happy which makes those around them happy.Now who could put a price tag on all that happiness? And isn't happiness and love what we're really all after?

[quinterbourne]

Obviously the improved alignment will give immediate results. I think the question going around is whether or not the shift of weight (distribution) has any affect.

[Steve Inman]

Obviously the improved alignment will give immediate results. I think the question going around is whether or not the shift of weight (distribution) has any affect.

I missed any earlier discussion on this topic. Hence this may have been covered before.

I can see two reasons this product could work:

1. Your instrument is initially out of alignment, and the product returns it to proper alignment. Possible and plausible if you are using compressible felt spacers for piston alignment.

2. The physics and the theory espoused at Mr. Baer's website. In my mind, however, the jury is still out on this one. Here is an explanation of the questions that come to my mind:

a. Whether by virtue of the small/dense O-ring or by virtue of the wide/soft felt washer, the mass of the piston IS held in contact with the valve cap, pushed there by the piston spring pressure.
b. In either case the force is the same, as the spring is not altered by the product.
c. In the case of the small/dense O-ring, the force is applied to the center of the valve cap.
d. In the case of the wide/soft felt washer, the force is applied to the entire valve cap (mostly).
e. HOWEVER, in both cases, the same overall force is transferred to the valve casing by the valve cap threads -- the the overall/total force is identical with either product.
f. So the only way I can see that there could be a difference is if the application of the force onto the valve cap top horizontal surface (not the threaded edges of the cap) interacts differently with the threaded edges when the O-ring is compared with the felt washer.
g. My opinion is that the felt washer should actually dampen the interaction between the mass of the piston and the top horizontal surface more than the dense O-ring. My opinion also is that the valve cap thickness ("adequate") compared with the upward force of the piston and its mass ("small") have a relationship that renders the coupling material insignificant to this problem of applied physics. I.e. -- in either case, approximately the same force with the same result is applied to the THREADED EDGES of the valve cap, where any damping force (the same damping force and IMO possibly a reduced damping force with the felt washers) is transferred to the valve casing and therefore to the tuba itself.
h. Therefore, I am inclined to discount the likelihood that there is a benefit due to the alleged damping effect of the pistons and the manner by which this effect is mechanically coupled to the top of the valve cap.
i. I believe there is a much more significant impact of damping the vibration of your instrument by the ways in which it contacts your body -- sitting on your leg(s), resting against your torso (or stomach in my case), resting your arm(s) on the body of the horn, etc.

The way to confirm is to find a mechanical engineer with access to software to perform a finite element analysis based on the material properties and physical sizes of the O-ring vs. the felt washer.

IMO, the bulk of the benefit of this product probably comes from bringing the piston valves into proper alignment. And I can clearly see how it could do a good job of this, compared to the previous set of old, worn, compressed felt washers the PVAK would replace. However I do not have the results of a mechanical FEA to confirm or disprove my thoughts, and I would welcome the opportunity to review such an analysis.

Now IF multiple users of the PVAK are able to come forward with data to establish that their valve alignment was close to ideal BEFORE application of the product, such that they can establish that the product did not have an appreciable affect to valve alignment, THEN I would be happy to entertain the theory that there is a physics-based element to the benefit obtained from this product -- but not until a significant number of such claims come forward. Of course, be prepared to submit boroscope data and impartial external opinions from others who heard your horn before and after.

From a more practical perspective -- when was the last time that YOU checked your valve alignment? Which of us owns a boroscope to even check? Which of us ever remembers or even considers that this could be an issue?

In spite of my questions regarding any benefits to the overall resonance of a horn, I would bet that significant benefit could be derived by guaranteeing long-term, precise alignment of your valves (Klaus' point agreed upon that the only way to obtain "perfect" alignment would be a custom installation). I would bet that most owners of an older horn would experience an improvement with this product, most likely coming from the improved alignment that would occur. And I would agree that this alignment improvement should be extremely long-lived.

I guess my only practical question would be: Does Mr. Baer offer a "money back if not delighted guarantee" for his "standard" kits? That would be important to me were I to consider such a product.

For your consideration,

[Steve Inman]

[ ... numerous good observations made, see above ....]

1. I should have read Klaus' post a bit more slowly and carefully. I could have simply said, "I agree with Klaus."

2. "I agree with Klaus."

Cheers,

[jtuba]

I guess my only practical question would be: Does Mr. Baer offer a "money back if not delighted guarantee" for his "standard" kits? That would be important to me were I to consider such a product.

Asked, but not yet answered here. We should just write and ask him I suppose.

[Rick Denney]

The way to confirm is to find a mechanical engineer with access to software to perform a finite element analysis based on the material properties and physical sizes of the O-ring vs. the felt washer.

No. Finite elements analysis does not live in the frequency domain, but rather analyzes how loads are distributed through structures.

A little common sense here: Any significant vibration lateral to the motion of the piston will transfer quite efficiently through the film of lubricant. Fluid is incompressible, and at the frequencies in question, moves too slowly to get out of the way. Any significant vibration that is axial to the piston may be damped to some extend by the felt. Is that damping significant? That would require spectrum analysis on a vibration table. But, again, common sense would suggest that even if the piston moves axially with respect to the casing as a result of vibration, that movement would at least be less than the vibration of the casing. Damping attenuates vibration; it does not amplify it.

Changing the damping characteristics of the washer might change the degree to which the piston will vibrate axially with respect to the casing. The shape of the O-ring versus a washer will change the damping--it will increase it. The smaller the contact area, the greater the stress for a given load (and the load is established by the spring). The greater the stress, the more the deflection for a given material. The greater the deflection, the greater the hysteresis. And damping results from hysteresis--the energy is not returned at the same rate that it is stored. The O-ring will be variable, because as it compresses, the cross-section increases. These effects can be compensated by choosing material of different hardness and hysteresis.

I cannot for the life of me imagine that this would have a significant effect on the sound or response of the instrument. But I learned a long time ago that high-end performers sense things I don't, and even if it's a placebo effect, the results may still be useful.

Achieving and maintaining proper alignment is another matter, and worth some effort to achieve, within the constraints permitted by the accuracy of the instrument's construction. I suspect any anecdotes describing how other musicians noticed a difference result from improving the valve alignment.

For me, any benefit from fiddling with the material is finding the balance between noise, feel, and maintenance of proper alignment.

By the way, I have carefully measured the ports on my Holton. The incoming ports don't measure the same as the outgoing ports on most of the valves, such that no matter what size felt I might use, there will be misalignments on one port or another. Said another way, one side of the valve doesn't measure the same as the other side, but both sides, of course, move the same distance. And the pair of ports in use when the valves are up don't measure the same as the pair in use when the valves are down. Even the diameter of the ports varies. These errors are noticeable when measuring to the nearest couple of thousandths of an inch. This isn't even considering that the fourth valve is very significantly different than the other three, requiring a different thickness of bumpers.

I have no intention of challenging someone's perception, especially the perception of someone with demonstrably better perception abilities than I have. But from a physical perspective, that's how I see it.

Rick "hoping to damp speculation about the physics involved" Denney

[Mikelynch]

OH SURE, Rick--just go bringing physics and rationality into the question! Now this thread probably won't continue for more than another 40 posts or so.

Thanks Heavens we can count on a future "PVAK Update" thread to move us away from all this science and analytical stuff . . .

[iiipopes]

I agree with Rick completely. If I had gone to engineering school instead of pursuing another profession, then I could have been as erudite in posting.

That imperceptible "feel" is what makes the difference in musicians, and what makes one way of doing things best for one musician, but not necessarily for another. Sometimes in spite of the physics involved.

I completely agree about the porting, as well. A couple of years ago I took a souzy (not the one I play now) to a tech for cleanup and alignment, and the horn came back playing worse. This in spite of his claim he "scoped" the ports. So, I demonstrated, got my money back, showed him the factory engraved lines on the valve stems, purchased an assortment of felts and corks from him, and set them myself. Everything theoretical about porting and alignment issues assumes perfect manufacture, which with valve porting is anything but "perfect." Best guess and compromise is usually all that can be achieved, with all due respect to Bob Reeves.

[james]

I find it interesting that the "pros" generally tend to praise the PVAK and the skeptics/critics are generally those who do not make a living playing their horn.

Am I implying that the "pros" know more about physics? No.
Am I implying that the pros have better aural senses? No.
Am I implying either group is a better "person"? No.

What I am implying is that pros (who play their horns everyday) have a GREAT appreciation for a product which aids in consistency. (Duh)

The Baer PVAK does that. As Alan has stated himself, "it ain't rocket science". This product was designed to eliminate the variance of felts experienced by those who play their horn everyday and compress felts within a week of use.

Now, I understand the issue is with the statement "frees the weight of the piston from the rest of the instrument." on Alan's site, and not the claim that the PVAK leads to a stable and long-lasting alignment.

However, non-pros have also stated on this board that there is negligible frequency difference between plastic, brass, and stainless mouthpieces possessing identical shape. This may also be a proven fact in the science of physics.....but I would bet that a lot of pros would disagree. I know the brass colleagues I perform in ensembles with would disagree that I sound the same on a Kellyburg as I do a Conn Helleburg.

Is it any different than playing 10 "identical" machine-made mouthpieces to find the one that works best? Or playing a dozen machine-made tubas to find the best one. In theory they would be identical with negligible difference. Same brass, same machine mold, same equipment, same factory, etc.(I'm not talking about hand-made here)

A non-pro may scoff at these subtle differences and conclude that we should "just pick one" b/c science proves they sound/feel/resonate the same way. A pro would come to a different conclusion.

(The top pros in just about any job will go through a similar selection process with their equipment. Ever heard how many footballs a kicker selects from and what they do to "tweak" it? Now tell me, how could 20 footballs with exact same shape, same weight, and same leather have a different "feel" to a kicker? Physics says they'll all react the same. That's why the NFL places the regulations it does)

All that said, when I had the PVAK installed on my tuba I immediately noticed a better response from my instrument. I noticed more resonance not only in the body of the main branch but IN THE VALVE CAPS as well (on the tips of my fingers). Is this is a placebo effect? Maybe. But, I know I wasn't expecting to feel the sensation in my fingertips. No one pointed it out to me.

In my opinion, I believe this is due to the TYPE of contact an O-ring makes as opposed to large felts. I know it's been explained, but I'm still not sure how this differs from using a tuba stand as Alan suggests. In the case of a tuba stand, the tuba doesn't WEIGH less either......so if using the same arguments as used with the PVAK, why does the tuba resonate more with a stand? Because it's less dampened and has less contact surface area. I believe the same effect occurs with the PVAK.

James (who has a lot of pro friends who are envious of what they deem a "simple but genious" product by Alan)

***Edited for spelling and to insert the correct quote from Alan's site***

[Alan Baer]

Ok boys,
You want it, you got it... If you don't like the PVAK, you send it back and I'll refund the money. Minus the amount that Paypal gouges me for each transaction. In regards to the question about taking a horn that is in line and realigning with the o rings. Been there done it.. My 6450 as well as another one in NYC, were aligned using my old method. ( stacked rubber washers) Using this method the horns played VERY close to the same, obviously with their own subtle differences. I then aligned my 6450 with the current PVAK. There was a major difference in the response and sound between the two instruments.. The second horn was then aligned using the PVAK, the same thing was noted, improved resonance and response. I've tried many methods of aligning valves and this is the method that works best for me, as well and may others who have tried it.
Have a Great Holiday!
Baer

[GC]

Rick,

I know that your Holton shows the inconsistency in manufacture that the 345's are famous for, and that it transcends the horrors of its mismatched valve and casing ports. I also understand that the vast majority of tubas everywere built before computer controlled manufacturing methods.

My question is this: are modern valve sets built by hand (most of which sets used in European factories are made by the Meinl consortium, aren't they?), or are they made by CNC machines? If they are, then an alignment kit made for the CNC-made valves would be much more likely to have a predictable and consistent effect than hand-made inconsistencies would allow, and the whole process would make a bit more sense. If the valves in the list of horns on the Baer web site were inconsistent because of sloppy hand-manufacture, then it would make less sense.

I know that you keep up with technical details, so I'm curious if you know the manufacturing methods behind the Meinl-made valve sets? Or am I completely barking up the wrong tree?

[iiipopes]

Thanks. A friend of mine is getting the PVAK on his tuba that has, admittedly, been hot-rodded so that if any tuba can take advantage of the PVAK, it is his. I'll have to try it and see what I think.

Again, Just like heavy valve caps or mouthpieces, it's not the PVAK so much as it is a combination of amateur playing that can't tell the difference combined with a lot of inherently not-able-to-be-perfectly-aligned tubas on which it can't make a difference, which will make for a lot of skepticism from the TNFJ.

So, getting the chance to spend some time with a tuba on which it has the potential to make a difference along with a guy who can tell the difference, give me a month or so, when our schedules can find some time to sit down for a reasonable amount of time, not just a quick blow, and I'll get back with what I think.

[Roger Lewis]

The comparison to Tiger Woods is not quite as accurate as I would like to see. You can practice all you want but if you have never had any guidance as to embouchure positioning or air flow or HOW to do lip slurs, or WHY scales are necessary, then your "improvements" will be very limited. However, if you can get lessons with Tiger Woods, and grasp the concepts and then apply them correctly, yes, you will get better. Will you be the next Tiger Woods? Unlikely, because talent is an issue as is perseverence and hand/eye coordination. Are you willing to make the sacrifices that Tiger Woods has made to become the greatest player on the planet?

Just my $0.02.

Roger

[Uncle Buck]

I don't think anyone on this thread has argued that the product does not produce good results. It seems to me that Klaus, Rick, et al. are simply noting the possibility that the product's results are attributable to its valve port alignment, and nothing else.

If the product provides superior alignment, that alone is worth the reasonable price, regardless of whether the other claims are legitimate or voodoo.

[imperialbari]

I don't think anyone on this thread has argued that the product does not produce good results. It seems to me that Klaus, Rick, et al. are simply noting the possibility that the product's results are attributable to its valve port alignment, and nothing else.

If the product provides superior alignment, that alone is worth the reasonable price, regardless of whether the other claims are legitimate or voodoo.

Good reading!

Only I still don’t like the element of uncertainty about the sales’ hype: is it based on a lack of knowledge about the physical phenomenons involved or is it intended to create a mystic aura for those understanding nothing anyway?

I also wonder why trumpets are made to a so low level consistency, that they have to be shipped for proper alignment, whereas tubas can be helped out without the very costly and risky element of shipping.

Or really I know exactly why: No tubist would ship his/hers instrument just to have its valves aligned. Hence there would be no sales of this product, which can be made by any competent repairman and even by some players well acquainted with instrument maintenance. And at a price more relevant to the product than to the orchestral seat of the maker.

Of course customers have to hype the product after having burned a lot of $$. This effect is well known in all sorts of markets.

Klaus