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In Reply to: RE: Sand, Bladders and ??? posted by Vinyl Valet on May 05, 2015 at 14:39:09
As I theorized (or read from others) it seemed that some components need vibe control by isolation, and others actually need coupling at some point. Most stuff (amps, power boxes, etc.) seem to need better isolation or damping, while speakers need some coupling in order to work properly. My theory is that boxes shouldn't be bouncy nor buzzy to work best, so damping at least is in order.
But speakers (whose cabinetry and screw points shouldn't buzz either) do need to push against something in order to work properly, so they'll have to be coupled to a surface somehow, which doesn't mean that the support won't benefit from isolation or coupling or a combination.
YOu can think and then try this out for yourself. That's just my theory.
Before all the manufacturing and expense compromises a speaker business makes, they work hard on the resonance characteristics of their cabinetry, so unless they goofed, you don't want to totally defeat that.
In the end some of the more experienced guys here will tell you that you're not "eliminating vibrations", rather you're doing "tone control" to tune the vibrational picture to suit your tastes and your room.
Follow Ups:
Let's think about this.
Pretend for the moment that your electronic components are vibration-sensitive instruments, not unlike an atomic force microscope.
You're listening to music anywhere from 78 - 105 db, a vibration-rich environment. Now no scientist worth his weight is going to perform his research with his atomic force microscope at a crowded disco on a Saturday night, yet that is exactly what we do with our own vibration-sensitive instruments.
It's safe to assume whatever air-borne vibrations that are striking your body are also striking your vibration-sensitive instruments' chassis' too. Moreover, you also have internally-generated vibrations via power supplies, motors, etc. that your sensitive instruments are plagued with.
If you think of a tuning fork and striking the tines, you should quickly understand that vibrations are captured in a moment in time but with nowhere to go, dissipate over an extended period of time.
Now picture your vibration-saturated sensitive instruments resting on kitty litter or an air-bladder or even on stock rubber footers. Where do you suppose that mechanical energy is going to go?
Your kitty litter or air-bladder has created a disconnect so that all the vibrations captured at the chassis remain in the chassis and will fully dissipate there as well.
First you should understand that vibrations are an energy and energy likes to travel and energy likes to attach itself to anything it can. If there is no exit path, it will travel the component seeking the most excitable components to release their energy there. However, if you successfully provide superior exit paths that allow the energy to escape the sensitive instrument before it starts to dissipate, well you can be assured there's no other upgrade that can compare to it. Not even close.
It's better to think of vibrational energy as electricity which is always seeking the most expedited path of least resistance to ground. That is exactly how mechanical energy behaves.
But since the entire universe is made up of various forms of vibration including electricity, it's even better to think of it this way:
Electricity behaves just like mechanical or vibrational energy in that it is always seeking the most expedient path of least resistance to ground.
The best illustration about what your sensitive instruments face is to think of a lightning rod. Unwanted energy is attracted to that lightning rod and it happens to be the best performance-oriented lightning rod in the world. But it has no grounding wire attached. What's going to happen to that dwelling when lightning strikes? The results are catastrophic.
But when a superior grounding wire is attached and at the other end is a superior grounding spike into the ground along with superior connections, that dwelling stands a very good chance of surviving even the worse electrical storms.
Ok, I'm rambling and it's late.
The point being here is it's against the laws of physic to isolate an object from all sources of vibration simultaneously. And when you isolate an object from one source of vibration, you inherently trap other sources of vibrations captured at the object. You can't win with this methodology, you can only lose just a bit less at best.
It's impossible though many smart fellers will die trying. Why, even in a vacuum chamber, the object would have to be levitating to potentially escape any vibrations.
So why does everybody and their mother go the vibration isolation route? Because for some thoughtless reason it seems to make common sense. But it is pretty thoughtless. When I first started dabbling with vibration control 15 years ago, I started off with the vibration isolation methodology because that's where everybody else was. Surely, everybody else can't be wrong? Read my lips.
The first and last question most always is, what about those nasty floor-borne vibrations?
I could ramble on about why I pay no attention to floor-borne vibrations (not shock and impact) because they are already heading toward ground but I won't. So I'll close with this next real life analogy:
You're sitting in your car at a stoplight and some kid drives up behind you in his car with his subwoofer pumping out the nastiest, most ill-defined rolling earthquake type of bass you've ever heard. You look in your rearview mirror but it's vibrating so violently you can't even tell if the kid is a boy or girl. You're stomach's churning and you're starting to think if you blew chunks, you might get some relief. So there's that kid sitting in his car which is resting on air-filled tires and there you are too, sitting in your car which is also resting on your air-filled tires and you're experiencing one of the most physically nauseating moments of your adult life because of the kid's subwoofer.
From whence are these vibrations coming? The ground or the air?
Are not your air-filled tires and the kid's very much like your air-filled bladder or perhaps your stock footers?
Using that same car at the stoplight analogy, how is the car resting on air-filled tires being continuously bombarded with vibrations from the other car's woofer (or even its own subwoofer) any different from a speaker or component? e.g. couldn't the rearview mirror vibrating violently be akin to a a transistor, op-amp, capacitor, tube, etc?
I've left stuff out but the point being of all this is vibration isolation is an invalid vibration-controlling methodology and always has been. Vibration isolation is nothing more than a grotesquely inferior version of the one true vibration controlling methodology which is resonant energy transfer.
If, and it may not be so, that in your endeavors with vibration isolation have resulted in minor improvements and not just sonic alterations, then it is because you're implementing less inferior executions of vibration isolation. For example, why the maple chopping boards? Is it not possible that few or some vibrations are able to escape to there and dissipate there?
"Your kitty litter or air-bladder has created a disconnect so that all the vibrations captured at the chassis remain in the chassis and will fully dissipate there as well."
This sounds good but is just wrong. The vibrations are absorbed within the bladder or kitty litter and are dissipated as heat. It should be obvious that some media will absorb more energy than others, but very little is "captured at the chassis remain in the chassis."
You're just being silly.Let's think about this. Now you didn't, but let's think about this.
First, it should be common knowledge that the air-borne vibrations are sound waves traveling through the air. In other words, the air becomes excited with sound vibrations. Yet, you're saying that when air is confined within a bladder, the air becomes an absorbent? Hardly.
What I speculate is happening with the air-filled bladder is that like a component's poorly anchored and secured cheap stamped sheet-metal top plate, is that the air within the bladder also becomes excited and hence, the bladder itself together with the air within will actually vibrate in sympathy with any vibrations transmitted from the component or even from the sound waves in the air outside making contact with the bladder.
As for sand or kitty litter, is not the mechanical energy more free to travel within the component than exit out in the kitty litter or sand? In other words, doesn't the litter or sand create a greater resistance for the mechanical energy? Doesn't energy always seek the path of least resistance?
Let's go back to the tuning fork held in your hand. Your hand may well be a reasonable substitute for the kitty litter and sand since it too makes for a very poor conductor for mechanical energy to travel. Yet, when the tines of that tuning fork held in your hand are struck, why do the tines continue to ring audibly upwards of 120 seconds or more?
Yet, according to your thinking, the tines shouldn't ring at all as the air temperature in the room is heating up, in which case the purpose of the tuning fork's existence (at least in the doctor's office) has been defeated.
As for at least the air-borne vibrations converting to heat and I suspect the internally-generated vibrations. Well, it is known by some that vibrations induce friction and friction induces heat, but generally that only observable or impacting when certain intensities or velocities are reached.
For example, when I open and shut my car door, there is friction at the hinges. And though there may well be an ever so slight change in hinge temperature, it is completely negligible, unless perhaps the car door weighed 5000 lbs. and is inducing horrific friction at the hinges with one swing of the door. Same thing if I open and shut the car door 20 times in 1 minute. Now if I were able to open and shut my car door 500 or 1000 times per minute you may be onto something.
If all vibrations transfer to heat as you seem to want to believe, then we'd all probably be listening to music in dead silence in our thongs. Rather than just you.
Edits: 05/07/15
I always felt that the theory of an air bladder under an audio device....Was "to roll with the punch"...The airborne vibrations produced in the music room would ultimately disturb the components chassis as well as it's electronic innards.
Rather than the airborne forces striking a fully resistant mass that will become inevitably excited....The fluidity of an air filled rubber tube
under the component would theoretically allow micro movement (vibration) to occur and dissipate.The benefit being that of a less harmful(distortional) effect on the music chain.
"What a great ride"!!
Forget for the moment what the component is placed on.Just focus on the vibration-sensitive instrument (component) itself. Is it or is it not being bombarded and becoming saturated with vibrations within? Is the mechanical energy stationary within the component or is it traveling throughout?
If an air-filled bladder is as excitable by vibrations as the air in the room, how is that bladder able to offer any relief? Might the bladder absorb a few vibrations along the way? Perhaps but doubtful. Might you even hear an audible difference or improvement. Doubtful. Even so why bother?
Might the easily excitable bladder act more like a mirror creating a resistance to keep the mechanical vibrations inside the sensitive instrument? Highly likely.
You really should give consideration to a high-performance lamp where everything from the wall plug to the lightbulb and every connection in between has an effect on the lightbulb's performance.
The more superior the electrical conduit the better performing the lightbulb. Try loosening the wires at the switch or the wall plug and the see what kind of performance the lightbulb provides. Besides the potential flickering, dimming, completely on and off, or an otherwise unstable light source, the lightbulb's lifespan is also greatly shortened.
Or think of the earth's ground which I and a few others would attest both electrical and mechanical energy are seeking. If you install a lighting rod kit, you don't just lay the grounding spike on top of the dirt. In fact, instructions make it very clear to pound that mother of a spike at least 6ft into the ground to make a superior connection with the earth.
When you build a architectural dwelling, you don't lay the foundation on top of the ground. You secure that foundation deep into the earth.
I would go so far as to attest that regardless of the industry, the foundation determines the ultimate performance of whatever is placed on top of it.
You could build a $5M home on an inferior foundation and you'd be lucky if the house lasted 3 years. Or you could build a $100,000 house on a superior foundation and that dwelling may last 300 to 500 hundred years.
"High-end" audio is no different. An improper or inferior foundation will induce the biggest performance limiting governor you'll ever encounter. A superior foundation will allow your components and system to soar far higher than even the designers thought possible.
You wanna' keep believing that vibration isolation is the only or superior vibration methodology? Fine. But why not challenge yourself to perform this little experiment. Place a live bookshelf speaker so some type of serious oscillator or vibrator on top of your components or rack.
Dollars-to-donuts says you will not hear any audible degradation in your playback system's sonics. Why? Because your components are already so saturated with trapped with air-borne and internally-generated vibrations, that it cannot sound any worse.
Moreover, if you really understood the sonic harm induced by under controlled vibrations that severely cripples the component's precision and accuracy , at the very least you'd roll your eyes every time you saw an ad with a speaker sitting on top of a component or rack. At the most, you'd be posting on blogs like this stating the advertiser must be a real nut job.
On another note. If you want to still think vibration isolation is a viable methodology, why choose an air-bladder where its contents are "light as air" and just as excitable.
Isn't a feather more easily excited by vibrations than a block of solid of metal or concrete?
Isn't air lighter than a feather?
Edits: 05/08/15
Hi Stehno,
I read your carefully thought through comments regarding the negative effect of resonance within the music chain..In fact I am in complete agreement with every point you made...I commented on the air bladder query within the limitations of that particular type of device..The fact that it will allow devices to 'roll with the punch" of airborne shock waves offers somewhat of an improvement over using nothing...In my own system and from very early on I have been a firm believer in mass damping and driving micro vibrations to ground...I think the only area that we may differ on is the use of sand...
In those instances where you cannot connect the drain points to a true base such as a poured concrete floor...(for example where a raised sub-floor)has been used...I have found that a good sized low profile box filled with 20 or 30 lbs of dry sand can be an effective method. It will allow a pathway for excess resonance in which to dissipate as heat within The millions of vibration reactive particulates. I have found that this method also provides for good isolation as well..In my set up every device is topped with heavy copper and sand filled boxes..and every thing is mounted on points...It is only after I spent much time experimenting and dealing with the issues of unwanted resonance being entrapped within components that I was able to hear how well my system could perform.
"What a great ride"!!
It's nice to know that we are in agreement. Well, sort of in agreement.I never use the term isolation and audio in a positive sense. Based on what I think I know about isolation and from what I stated earlier, it simply is impossible to isolate all sources of vibrations simultaneously and when isolate one source you instantly trap one or more other sources of vibrations captured at the object.
As stated earlier and in the paragraph above we also disagree about the sand and the transfer of heat in this application. But sand inside a hollowed metal stand is better than nothing as it does make for a good mass loading weight helping to ensure the stand better connects with the sub-flooring underneath. But make no mistake, the mechanical energy is transferring via the metal stand, not the sand within.
Extreme forms of connecting disparate objects is paramount when attempting to create a superior mechanical conduit. Mechanical energy does not travel as fast as electrical energy and hence it takes just a little compromise to create a large bottleneck preventing mechanical energy from traveling. If it cannot easily transfer from the first disparate object to the second disparate object, it will remain traveling within this first and start dissipating there.
You cannot create a superior mechanical conduit to sand. Concrete yes, sand no.
I always focus on the most extreme forms of tight coupling and using the hardest materials reasonably available. To the best of my knowledge that is the only hope of creating a superior mechanical conduit.
Edits: 05/10/15
nt
Maybe similar, but not the same.
Isolation can produce the results you're describing. That is, if it were truly just a containment function, and I'm not so sure that's always the case.
Damping is actually the dissipation function, so the vibes do go somewhere and get converted to another form of energy, usually heat, or into another part of the sonic spectrum that is less annoying to you. At least that's been my understanding.
For boxed components I use damping and coupling, rather than isolation. Then I use isolation/damping for the platforms they sit on. Pretty much the same for speakers I use.
You are absolutely correct that music (and the universe for that matter) is all about vibration, so any notion of totally eliminating vibration is not only infeasible but also antithetical to sound.
I disagree with your comment about finding similar results using isolation. Vibration isolation (an impossibility) and mechanical energy transfer are diametrically opposed strategies and methodologies.
That's like saying God sits on a mountain top and there are many paths to Him. In essence you'd be saying God (or in this case superior vibration management) speaks with forked tongue,
One of the difference is your use of the word containment. The better word is trapped. I would never attempt to contain or trap mechanical energy. That's what everybody is already doing and I have no desire to be like them in their endeavors to defeat basic laws of physics.
Sounds like a good plan. one can dampen the shelf, isolate the chassis and then dampen the isolated chassis. With DIY that's not too expensive.
I think ecumenical is the appropriate word here. No thanks.
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