It depends whether the resonators are easily to refit. I think Ferree's or someone had pads with this shape, but I think they were riveted.

You need to talk to your sax tech about what pads they use and whether they are willing to reuse the old ones.

 

It depends whether the resonators are easily to refit. I think Ferree's or someone had pads with this shape...

Yes!

https://www.ferreestoolsinc.com/pages/b56-ferree-s-cone-resonator-standard-thickness-sax-pads

"The tried and true B56 Elliptical Cone Resonator Sax Pads have convex resonators made of the same material as our Selmer Type resonators. The special cone shape provides 360° airflow management and sound reflection to direct the sound and air out from under the pad, instead of bouncing it back into the sax, greatly improving resonance and performance. It is molded with a solid construction and flat back. The B56 Cone Resonator fits the pad naturally and blends well with other resonators when being used as a replacement. By half millimeters. Cones are brown only."

It doesn't say whether they are riveted.

I find it interesting that they are both "greatly improving resonance and performance" and "blends well with other resonators". Is there a difference or not?

 

I would not go to the trouble of reusing the old boosters. I doubt if they do anything more than any other resonator. I tend to stick with the Selmer brown nylon type on everything unless I'm intent on restoring to original, like a Martin or old Conn.

 

Likewise, totally.

 

I mean, if they're going to give me greatly improved resonance and performance, after all...

 

I wonder if that photo shows a Ferrees "parabolic" - funny looking parabola!!! - plastic resonator over a flat metal washer, to cover more area?

I bought stock of those pointed plastic resonators decades ago, before I became so cynical about marketing hype. They sit in the drawers, unused.
Now when I read that hype I think what a load of made-up BS.

 

"The special cone shape provides 360° airflow management and sound reflection to direct the sound and air out from under the pad, instead of bouncing it back into the sax, greatly improving resonance and performance."

Not quite sure what this means..."direct the sound and air out from under the pad".

Selmer engineers determined in the early 1960s (and probably long before), it is not just how the air is reflected through the open tone holes, but also how effecientely it is reflected back into the instrument on closed tone holes. See more on this blog article on the Morgan Mouthpieces Website:

https://www.morganmouthpieces.com/blogs/news/162689607-a-conversation-that-resonated

There are scientific reasons why Selmer switched from metal domes to nylon domes in the 60s. A lot of research went into determining the size and shape of the resonators.

 

There are scientific reasons why Selmer switched from metal domes to nylon domes in the 60s. A lot of research went into determining the size and shape of the resonators.

I thought that the primary scientific reason is based on the complex theory of the "coefficient of currency." Plastic resonators are cheaper. If it were more complex than that, each pad would have it's own size resonator and maybe its own unique shape. But after a lot of research, Selmer (and P.T. Barnum) determined that the public isn't that smart.

Mark

 

Decent article - thanks Dave.

Discusses the balancing of shape both for reflecting sound out through the tone hole and for reflecting back into the horn when the pad is closed. I think the parabolic cones would be balanced more toward reflecting out but would probably be not as ideal when the pad is closed. Also mentions the obvious that the switch to nylon resonators was completely for weight savings rather than sound.

I'll most likely put flat resonators on the Conn, as I've had on all my horns save for Noyeks I had on my Martin bari but swapped out eventually for flat. Maybe I can find some flat nylon resonators

"When the sound waves reflect off a resonator on an open key, an optimal dome shape helps reflect the sound waves out of the tone hole. More importantly though is when sound waves reflect off a resonator on a CLOSED key, the dome shape helps reflect the sound down the body of the interior of the horn. The arc or height of the dome of the resonator is critical and must do both functions with minimal turbulence of the airflow. If all you are concerned about is reflecting sound out of a tone hole, then you would use a different shape and conversely, if you were just concerned about reflecting sound waves down the body of the horn, you would also use a different shape. Because you need the resonator to perform both functions, you have to find a shape that will perform both functions well. "

 

Unless I am mistaken, the term "reflection" is used incorrectly here:

What happens at an open tone hole is that air vibrates in and out of it very rapidly - at the frequency of the note being played. Nothing more"
I think it is bit far fetched to think a very shallow cone in the middle of the resonator would aid this process.
(This in and out vibration of air is the means by which a travelling wave is "reflected" - technical term - back up the instrument, the end product being a "standing wave".
This air wooshing in and out of the tone hole is the beginning of the traveling wave that travels to the listeners ears.

For a closed tone hole, there is no reflection. The air is vibrating up and down the instrument in some locations (pressure nodes) and in others, the pressure antinodes (or movement nodes) there is an oscillation of air pressure. Kost locations will have a mixture of two two. What the resonator does is provide a more rigid surface, like the metal bore, that reduces the muffling effect of the soft pads. (The pads damp the air vibration and pressure oscillation.) I doubt that the shape has any relevance. It is the rigidity that is relevant, and especially the surface area covered, of course. Thicker plastic would have sufficient rigidity to do the job, and so would thin metal. I doubt that thick metal would do it any better, and it certainly presents weight issues for some keys.

There is no reflection anywhere in the sense that light is reflected in a mirror, or a billiard ball off a cushion.

... unless I am mistaken.
But for marketing purposes manufacturers and others will invent anything they like, to baffle purchasers.

 

Not to bicker but, to bicker a bit... I agree with the bottom line and practical effect of what your saying, and most of the details, including the likely effects of resonator shapes, 'though I'm willing to consider maybe there's some small effect if someone I like swears to it.

Maybe this is just about languaging... To say air "vibrates in and out" of a tonehole is well intended but probably not technically correct as the distances air actually moves in a sound wave is miniscule, especially in higher frequencies. Sound waves of course do reflect, and that term is appropriately used to describe sound (which is small movements of air -"compression and rarification of air molecules"- as they always said in class bouncing off surfaces in and of the horn. Those sound waves are bouncing around inside a horn as well as traveling out through any path possible - bells, necks, leaks, toneholes... While the fundamental and perhaps lower harmonics may be simply resonating, higher harmonics are no doubt reflecting all over the place. I think that's why something like a waffled resonator can have an effect. If I remember correctly, in cylindrical bore instruments, the sound actually reflects off the open hole at the end of the tube. So I'm onboard with the word reflection, I guess is all I'm saying

If those parabolic resonators were sterling or something I might re-use them just for the novel look. But what you've got me thinking now is flat carbon fiber. Stiff and maybe even lighter than nylon. On black 'roo pads, black on black

 

Re-reading both our posts, Gordon, I'm not sure I added much with the above But I'm thinking now about motorcycle exhausts, where you in some cases want to reflect a pressure wave back up the pipe to stop the flow out the exhaust port - most particularly in two-strokes. Mufflers work with a combination of sound absorbing material, like a pad would be, and hard surfaces that bounce the sound around so that it both interferes with itself and also has more time to be absorbed by the materials of the muffler. Low frequencies travel around corners better than high frequencies. High frequencies would be more likely to bounce off an open pad with a flat resonator, back into the horn vs exiting, than off a dome/cone/pyramid/whatever. Just streaming thought... I think the opportunity is there for a difference between a shaped resonator and a flat one. If a dome can make a difference than so can any other shape. None of this is going to have any impact however on my choice of resonators....

 

We'll have to agree to disagree.
1. I think the images taught at school level are simplistic.
2. I don't go along with the concept of sound "bouncing around" in a woodwind air column. A pressure wave travels from one end to the other, "bounces" back from the open end, and on the way back up the instrument, interferes with the initial wave, creating a "standing wave" which no longer resembles the two waves it was made from. A standing wave is not like a wave in water, bouncing off things, and should not be pictured as such.
3. You wrote "To say air "vibrates in and out" of a tonehole is well intended but probably not technically correct as the distances air actually moves in a sound wave is miniscule" Technically that is exactly what happens at a tone hole. Yes, the amplitude is small in large tone holes, but so what? It has enough amplitude to be heard when that initiated travelling wave leaves the open tone hole and reaches our ears.

 

I refuse to disagree Following is how I understand things to be. I'm sure you're right in the fundamental principles of sound in saxophones but I'm really looking at the more subtle end of things where resonator shape might have any effect (as some manufacturers seem to believe).

Re. 1, Basic physics of sound have been well understood for many decades. And indeed the basic mechanism of sound propagation is essentially quite simple.
Re. 2, The sounds that can bounce around meaningfully are the higher frequencies, as their wavelengths get much shorter than the horn. Wavelength at 5 kHz is a few inches. Higher frequencies are of course even smaller, and those sound waves bounce off the details of the inner horn. Same way echolocation works, whether by whales or bats. Regarding standing waves, a standing wave in water in fact acts much like a standing wave in air. The pressure wave "bouncing" off the open end is a reflection of the wave. That's true even with a rope tied at one end - all these waves behave consistently with each other. The open end of the horn reflecting the wave is the same as the tied end of the rope, or the wall of a wave tank. Sound can bounce off of air but not off of metal?
Re. 3, When I said "air vibrates in and out" is inaccurate, most of the air involved in the vibration does not actually leave or enter the horn - only a tiny fraction of the air in the horn or the air outside of the horn actually enters or leaves the horn, and by microscopic amounts. The sound "wave", which is quite literally the compression and rarification of molecules, propagates but no air actually travels anywhere, save for the amount being breathed into the horn. As with a wave in the ocean or a rope being waved up and down, only the wave is actually going anywhere. The molecules of air are just vibrating a tiny distance, vs moving in and out of the horn.

 

Anyone tried plain riveted pads wrapped with tinfoil? Just to see if there is an instant changed. Seems like everything else has been tried once why not that?

 

mark_m, We simply are not communicating.
1. I was never writing about the slow movement of air through the sax (from the player's mouth). Where did you get that idea?
2. I totally disagree with the use of the word "bounce" with respect to sound "waves" and the wall of the bore.
3. Yes, a standing wave can exist in water in unusual and special circumstances, eg sometimes at a river mouth, but a standing wave does travel anywhere so it cannot "bounce" off anything. (It is created by two waves that travel in opposite directions, superimposed upon each other. The only "bouncing" that occurs is that the second of these waves is created by the first wave "bouncing" off the open end of the sax, or the first open tlone hold. But that is only to create the second wave. Once they are superimposed the end result is no travelling wave within the sax.)
4. As regards the oscillating air movement at tone holes, that is the initiator of the travelling wave that reaches your ear:
You seem to be saying that this is minute and of no consequence, which tells me that your concepts of acoustics is ... hmmm, dodgy to say the least.
If you cannot grasp this, then how about consider an experiment...
Take a flute adjustment feeler, i.e. a short, narrow strip of say mylar film, 0.02mm thick, mounted at one end in a handle, or glued to a short stick.
Blow a 1st octave G in front of a mirror. Hold the feeler near the 1st open tone hole, i.e. under the F# pad.
The feeler can be seen to vibrate with the air oscillating rapidly in and out of the tone hole. The amplitude is visibly around 4mm and the frequency is of course for fingered G/Sounded Bb, namely around 233 Hz (for alto sax).

 

I agree re not communicating... I'll take one more shot at communication, last try...
Re. 1: I did not interpret that you were talking about breath moving through the sax; I simply stated that no air is actually traveling anywhere in the propogation of sound, "save for the amount being breathed into the horn". That wasn't an interpretation of anything you had said.
Re. 2: "Bounce" and "Reflect" are equivalent terms regarding sound waves. I think we can agree that a metallic wall can reflect a sound wave, as a starting point.
Re. 3: I've never talked about standing waves reflecting. Even 'though they only exist because of a reflection. I've talked about higher frequency waves, where the wavelength is substantially shorter, shorter perhaps than even the diameter of the horn, there is ample opportunity for those frequencies to be reflected around. It is in fact very useful to study water to understand wave behavior. We spent a semester in college physics with wave tanks. Much of wave behavior is not only shared between water and air, but even extend to light when being considered as waves. Reflections, propagation, interference, for instance, are substantially consistent between these.
Re. 4: Yes of course. My only point, which was not in conflict with anything you had said, was that the description in the Morgan paper was perhaps confusingly worded in talking about "air vibrating in and out" of the tonehole. And only to say that it infers (or at least to me) that air is moving in and out of the tonehole. If you want to measure tiny distances and call that "in and out", then fine. The distance, at high frequencies, that air molecules are moving back and forth is so small it would be hard to say at what point a molecule might be in or out. The sound wave is what travels through the tonehole to one's ear.
Also Re. 4: I did not remotely say that the minute movement of air molecules is of no consequence. It is the entirety of what sound is. To call my concepts of acoustics "dodgy at best" is probably too far removed from the topic to justify more than a mention if at all.

Regarding your suggested experiment, I don't need to do it to know and understand that it would be as you describe. Lower frequencies will have much higher amplitudes of movement, just as a woofer has greater excursion than a tweeter. I was discussing high frequencies with short wavelengths (think tweeter) which have much lower amplitude. And that discussion was specifically in relation to the use of the word "reflection" off of resonators. Which I think is a completely acceptable use of the term especially in that context. Just to bring the conversation back to what started it. Reflections of high frequencies are of great consequence and the design of high frequency drivers for audio goes deeply into controlling reflections to avoid interference and phase issues. In the same way, reflections of high frequencies in a horn could potentially have an effect on tone characteristics. Noyek or "waffled" resonators, in my experience, have a definite effect on upper harmonics. I don't know to what, other than reflections, one would attribute that.

 

I'm glad you have clarified some of what you wrote.

You don't need to condescendingly lecture me on college physics. I studied as much as you did.

To be pedantic about what is in and what is out out of a tone hole is unhelpful. We are talking about sound. The sound as it leaves the sax, i.e. a compression wave, constitutes nothing other than very small oscillations, and these are in the direction of in and out of the tone hole.

You write of high frequency waves traversing across the bore. The sounds we hear are harmonics of the fundamental, and all produced by the complex standing wave, which is stands up and down the bore. If waves are "bouncing" across the bore then they would have a wavelength related to the bore, not the length. And I doubt they would initiate an audible compression wave from the tone hole, any more than ripples across a long wave tank would influence the highly-structured standing wave that is generated from end to end in that wave tank.

Regarding my experiment, are you suggesting that because the higher frequency sounds have smaller amplitude they no longer involve oscillation of air at the open tone hole. We both know that is not true.

As for speaker drivers. I am very familiar with the flaws in their design, having been involved in helping my nephews design this relatively flawless, world-beating technology:
https://wingacoustics.com/

 

Gordon, I'm sorry if you interpreted anything as condescending. I have simply attempted to explain my understanding of things to the best of my ability. I make absolutely no assumptions about your or anyone's education on the topic. (Nor should you of mine).

Also I think some of your responses would be answered by more careful reading of my post. So I will not attempt to post further to this conversation, no hard feelings, I just don't see it going anywhere.
best
-Mark

 

Gordon you seem to be more focused on being right and proving that I know nothing, than reading carefully and making an attempt to actually understand rather than pick apart, and having a constructive conversation that adds rather than subtracts. I hope that's somehow rewarding for you.

 

These have been around for years I've seen them on many an old sax I've had in for repair-nothing special really. There is nothing new about 'tweaking' horns and all the hype that goes with it you've only got to look at some of the old catalogues and adverts from way back in the '40's and '50 's that illustrate this point.

 

I'm sure that's true. I can't imagine resonators making any major difference other than slight volume changes. I did read that they can slightly affect pitch by occupying more of the tonehole volume. I also read that, if I got this right, the absorption of pads without resonators can help pull inharmonic partials into tune with the true harmonic. Again that I'd think these effects would have to be miniscule.

I do imagine they could make small differences in tone. The waffled resonators I had in my Martin bari added some texture, which I interpret as crossed reflections from the irregular surface causing interference in upper partials; maybe others have experienced something like this as well. I had them swapped out for flat because I thought they might have been making it hard for me to get altissimo working on that horn. But it actually wasn't any better with the flat ones, it was just me

Thanks

 

Sorry mark_m, I'm giving up. We have different understandings of the meanings of some of the terms used in wave theory. We have different concepts of the wave phenomena themselves.

I tried to explain to you; communication clearly failed.
You tried to explain to me; communication failed.

The conversation is going nowhere.

 

Agreed and no need to continue flogging it