Vibration Management

[KlausR.]

...discovering you have a problem, solves the problem.

Obviously. But has this been done, I mean in a scientific manner with appropriate controls of the parameters?

 

[Mike Lavigne]

Obviously. But has this been done, I mean in a scientific manner with appropriate controls of the parameters?

sure.

this is how science and industry do it at the top of the food chain. since every installation is different, there are processes involved in finding appropriate site specific applications.

serious stuff.

 

[Barry2013]

Hi Dave
Just wondering if you have ever heard the Townshend Rock V turntable. It has a paddle you fill with silicon fluid and a lug to fit to the tonearm so the tonearm is additionally insulated from vibration over and above the sprung suspension. Pretty rare beast I know but very good. I haven't come across any other make that uses the same system.
There is a photo of mine on the Entreq Tellus thread.

 

[CGabriel]

As I've said before, the first step of such research would have to be to determine whether there is a problem or not. Once the existence of the problem has been demonstrated, one can start investigating solutions. In this case one could, for instance, connect the system to the speakers with wire long enough to reach into the room next to the listening room, play a tune with system and speakers in the listening room, measure and listen blind, move the system to the other room, measure and listen blind. With system and speakers physically separated the effects of airborne vibrations should be eliminated.

Have such tests ever been performed to see whether or not vibration of amps etc. is really a problem?

Klaus

Some of us have already done enough of this testing to know there is a real issue. But some people need to do the tests themselves to be convinced. I am one of those people and it sounds like you are the same. If you have enough motivation you may want to do the tests you just described.

 

[Stacore]

Jarek,

While I understand your desire to disengage from this specific thread, I would encourage you to continue to share your knowledge and experience with the population. It is always beneficial to hear from someone with a core design philosophy who has translated that into a commercially successful product line. I personally believe that design philosophies are important but execution and implementation effectiveness may be more important to the success of a product. To use speakers as an example, I have experienced great sound qualities from two diametrically opposed points of view on cabinet design philosophy. One design advocates an acoustically inert goal for the cabinet while the other design attempts to design the cabinet as a musical instrument allowing vibration to move quickly through the cabinet. And conversely, I have experienced examples from each design perspective that were not particularly attractive. I do agree with steno that more attention and research is important to understand the impact of vibration on the performance of audio equipment. I sounds like he has a design philosophy that he believes in based on years of research. I can understand if he wants to protect ideas that he may consider proprietary but if he has truly given up on making them a commercial success, it would be nice if he shared more about his racks and ideas.

Caelin and others,

Thank you for the interest in what I can offer to the community. I'm happy to share my knowledge and did not want to disengage from this thread.
I just find it inappropriate and useless to go into arguments with another manufacturers - it is clear we all stand by what we are doing. Otherwise why doing it?
Now, since Stehno is not an active manufacturer, I can sort of think aloud more freely without potential conflicts.

How I see it, feel free to correct if I'm wrong:
First of all, all of the energy transfer we are discussing here is resonant in nature.
The degree to which non-resonant modes are excited in the structures such as chassis, racks, etc
can be in the vast majority of situations neglected. Second, the mental image of traveling vibrations
is OK but for a very short time: Speeds of sound in materials in questions are in kilometers per second,
even for woods! So very quickly if there are reflections from the boundaries of materials, standing wave patterns appear
and all looks like a complicated vibrating "drum".
Of course if there are little reflections due to the proper impedance matching, there are no standing waves
and this is how I understand drainage. To design for it on purpose is a complicated thing : Two basic wave types
(compression and transversal/shear) plus the zoology of impedances makes it hard.
But not impossible - I believe good tonerams achieve this, taking the energy away from the cartridge and dissipating in the bearings.

This brings to the two basic vibration control schools: Take away and dissipate somewhere or start dissipating immediately.
First would be a stiff rack, with high resonant frequencies. IMO, this is the type of a rack is optimal for isolation platforms:
You want the resonant modes to be of the type and frequencies such that the platform will easily eat them.
The rack damps little and leaves the platform to eat the vibrations. You can call it "efficient resonant transfer"
We are approaching a rack design optimized for our platforms and this is the starting point.
Modern optical tables use this principle too.

Second school is a soft rack, with low natural frequencies. The rack tries to absorb and dissipate the vibrations on its own,
bending and wobbling. Best if the first (=most important) resonances are below the audible range. This is some sort of a simple
mechanical isolation.

Those two schools are not necessarily mutually exclusive: A rack can be stiff for certain movements and soft for the other...which complicates
the things even more.

Cheers,

 

[microstrip]

Obviously. But has this been done, I mean in a scientific manner with appropriate controls of the parameters?

No. If we were waiting for the results of such tests the high-end (stereo high-quality sound reproduction) would not exist.

We do not have results of such scientific tests for electronic devices, why should we expect to have them for the so called tweaks?

 

[stehno]

So according to you all those companies who design and manufacture industrial vibration isolation devices, Newport.com for instance, don't have a clue, and their customers don't have a clue either. Which laws of nature precisely do isolation devices offend?

Oh, by no means would I say those practicing vibration isolation don't have a clue. Obviously, many highly intelligent and even some wise and logical types spend their entire lifetimes engaged in such matters.

What I suspect is that the most basic premise of mechanical energy has been completely overlooked with an incorrect assumption by essentially everybody. Isolation just frickin' makes sense to us all and perhaps since we were 7 or 8 years old and we tried to isolate the review mirror on our bicycles to keep it from vibrating and the solution worked.

Or perhaps it's the oh-so-common story we hear in high-end audio where the proud owner of a SOTA-level TT hosted a party and a heavy-set person was dancing in front of the TT and caused his $5k stylus to jump 13 grooves and the next day he goes out to the audio forums crying for help so this never happens again. In both cases, that's shock and impact and has nothing directly to do with superior methods of managing much smaller vibrations that continuously bombard our sensitive components.

Essentially everybody who encounters a situation where vibrations have a negative affect on anything whatsoever, even by reflex alone, the thought of isolation comes to mind almost as though we were born with this instinct. Isolation is such a universal concept that it's become a no brainer and everybody thinks the scientifics types figured this one out centuries ago and hence everybody has moved on to more important things to concern themselves with like very advanced and complicated means of isolating.

Three of mechanical energy's behaviors I'm most interested in are:

1) Mechanical energy first and foremost seeks to travel - as I speculate does most/all forms of energy at some level.
2) Left unimpeded mechanical energy seeks the most expedient path of least resistence to ground - as I suspect does most/all forms of energy at some level.
3) When mechanical energy's travel is impeded, then it will release / scatter its energy at the most easily excitable objects within its trapped vicinity - as I speculate does most/all forms of energy at some level.​

Hence, if the first principle of mechanical enegy is to travel, why would I want to prevent that from happening? Especially when there are at least 3 primary sources of vibrations and if I impede (isolate) the travel of energy from one source, I've instantaneously trapped all the vibrations entering from other sources. For example. The isolationist claims our most destructive source of vibrations rise up out of the floor toward the sensitive component. But when the isolationist blocks the path of these floor-borne vibrations from climbing up the rack, he has instantaneously trapped all internally-generated vibrations (think power supplies, motors, wires, et al) so they cannot travel and cannot evacuate. Same with air-borne vibrations captured at the chassis. Hence, this constant continous bombardment of vibrations are trapped at the chassis with nowhere to go, hence their crippling affect. To make matters worse, I speculate the isolationist has saved their components from the vibrations that causes by far the least amount of harm.

In other words, I suspect the isolatist has assumed incorrectly on the most basic of all priciples of mechanical energy. And if one is incorrect about the most basic of principles, it matters not how intelligent or correct they may be in their subsequent equations, thinking, designs, executions, etc any further down the road. If they stay true to that initial falsehood, it can only take them further from the truth.

I have a few questions of my own if you don't mind.

1) As one committed 100% to mechanical enery transfer, I use hard rigid materials and designs only and all tightly coupled. Why would a true isolationist (is there any other kind?) use even a single piece of material that was harder or more rigid than say Sorbathane? And why would they have even one connection fastened tightly?

2) If as the isolationist says, the floor-borne vibrations induce the most harm and that's what we need to protect our sensitive components from it, why do their solutions not follow their mindset? If I wanted to severe / decouple any electricity from reaching a lamp's light buib, I'd cut the electrical wire and I'm done. What's so difficult to understand and how much science is required to make that happen?

3) Water is intended to exit out of the bathtub's drain. Let's say you had sewage water coming up out of your bathtub's drain so you wedge a rubber stopper in there to prevent that from happening. Then your 3-year-old turns on the bathtub faucet? Where's that water from the faucet going and what will happen to that bathtub?

4) You're at a stoplight and suddenly your stomach wrenches with vibration as is your entire car. It's the car behind you with his four 18-inch subwoofers cranked. You look in your rearview mirror to identify the culprit, but the mirror is vibrating so violently, it's all just one big blur. From whence are the vibrations entering your car?

SoStill waiting for your explanation why steel should provide better draining than wood when the laws of physics clearly show that this is not the case?

Perhaps for much the same reason you don't see many really nice looking Mexican Cocobolo wood tuning forks in doctors' offices.

 

[KlausR.]

sure. this is how science and industry do it at the top of the food chain. since every installation is different, there are processes involved in finding appropriate site specific applications. serious stuff.

Looks very professional indeed. However, I can't see anything relating to audio components. I further can't see anything relating to controlled listening tests. Further I don't think that mechanical decoupling is a solution for airborne sound.

So once again, where is the evidence that vibration in audio components is a problem?

 

[KlausR.]

Some of us have already done enough of this testing to know there is a real issue.

You mean, with appropriate controls of all test parameters, with enough listeners to be able to do valid statistics?

But some people need to do the tests themselves to be convinced. I am one of those people and it sounds like you are the same. If you have enough motivation you may want to do the tests you just described.

I did some testing in other areas: cables, preamp vs no preamp, MD vs CD, different surfaces the CD player was placed on, I borrowed some of Franck Tchang's metal bowls. In none of the cases I could hear a difference or an effect. These tests, however, were done without any controls and in view of the obvious difficulties to set up such tests with appropriate protocols it is close to impossible for the layman to perform such tests. Therefore I ask manufacturers to do the tests and convince me. Tests published in peer-reviewed technical/scientific journals would be fine as well.

Klaus

 

[stehno]

Tbh, unless Stehno comes up w compelling reasons to go down his route, Jarek and his Stacore Adv product remains in Pole position (pun fully intended) to get my support re dedicated isoln, at least of tt
Stehnos suppositions remain v interesting, but theories and a few photos aside, I still have no real overview of what he's providing
Added to the fact he's not in current manufacturing mode, I look twds his proposals
I'm liking the performance v price ratio of the Minus K, but it's proving a bugger to get install to be "set and forget", and despite its impressive specs ie isoln good to 0.8Hz, passive pneumatic springs Stacore Adv and active piezo electric Herzan-like Kuraka look more user-friendly
Re Stehno's ideas, I would v much like to investigate further
Certainly w most of my components sounding great and no desire to upgrade in a hurry, room acoustics, power and cabling fully sorted, vibration management is my "last frontier" potential upgrade
I've had good results from Symposium, both racks and RollerBlocks, promising results from the Accurion i4Large trial under tt some years ago, dramatic (but for me, wrong) results from Ulra5s, and first good, then not so good, results w Shun Mook Diamond Resonators
So I have a reasonable set of data points to call on further investigations

Marc, I’m glad to hear you say this about Stacore’s products being in pole position. You seem like a pleasant gent, but to be honest I couldn’t help but think this was just a test of sorts and I really don’t have much spare time for that sort of thing right now. So I’m gonna’ gracefully bow out by saying thanks for the opportunity but no thanks. Also, I’m glad you’ve found at least some of the things I’ve said interesting and I hope you give them consideration in your search for superior vibration mgmt.
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Folsom, you asked me the other day how I might rank my design and you weren’t satisfied with my somewhat diplomatic response so I’m gonna’ be frank. At this moment with about 80% of it's extraordinary performance being due solely to the rack, I seriously doubt there exists a playback system anywhere at any cost that can match the level of musicality of my quite humble but extremely well-thought-out system.
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Since joining WBF and perhaps like others, from time to time I just try to share some of my experiences about various aspects of our playback systems including but not limited to areas like speaker placement, burn-in, cryo-treatment methods, less is more strategies, etc. But as mentioned I have a special passion for superior forms of AC mgmt and especially superior forms of vibration mgmt. because these two areas make up the very foundation of every last playback system whether inferior or superior. And as I said before, in most any industry it is the foundation that that ultimately determines the performance levels of what’s resting on it.

For the record, I’ve never tried to sell anybody here anything and I didn’t even start this thread. But I’m glad to have the opportunity to share at a bit deeper level a few things I’ve learned over the years about extreme forms of vibration mgmt. and more importantly, what has been sorely lacking from even the industry’s very best playback systems.

As mentioned I’ve no formal education in engineering, physics, nor the sciences. If I did, I guarantee you I never would have even started down this path. Rather, nearly everything I’ve learned about superior and extreme forms of vibration mgmt. has been solely by experimenting – which it seems with the invention of the internet may be a lost art . And in threads such as these, I think I do a fairly good job holding my own against some very intelligent science types. I’m also glad to see that for perhaps the first time at least a few have given my input on vibration mgmt their consideration.

But when the science types come out demanding proof, dismissing claims, reciting “facts” from science books, etc. it usually just becomes frustrating where battles are won and lost solely on the internet, (which usually has little to do with reality). Especially since I’ve got no such measurements, proof, or scientific evidence to substantiate my claims.

But it is the insightful one who realizes not everything in this world has already been invented, not every science minded type is worth their weight, nor does a lack of evidence disprove one’s claim. I may make seemingly outlandish performance claims while others attempt to defeat those claims never having experienced my design and perhaps never having given resonance energy transfer more than a grin, assuming they’ve even heard of it. But it’s important to realize that all the science knowledge in the world cannot disprove a working model. Bumble bees do actually fly.

Since I don’t have textbook science on my side, and just to provide a hint of what this industry has been lacking all these years including the lost thousands of hours of being immersed in wonderful music that can indeed sound so much closer to the live performance, I thought I’d share just a few short 2010 era emails from my Hong Kong distributor upon installing their first of 2 racks they purchased for their two $500k showroom systems. It’s been almost 7 years and I was never asked to keep these confidential and I’ve not shared them until now.

Bear in mind, the version of racks they had are at best 40 –50% of the potential of my current version and these are comments only in the first few days of settling in. How they got such performance gains on the first few days is beyond me.

Day 1

On 10/30/10, 12:01 AM, "AE" <info@audioexotics.com> wrote:

U can sleep now. Because my first impression (everything not warmed up yet) is the sound is very natural and fast.
I am out for lunch now. Report more tomorrow.
Sent from my iPhone​

Day 2

From: AE <info@audioexotics.com>
Date: Saturday, October 30, 2010 at 9:16 AM
To: Dad <jstehno@comcast.net>
Subject: Re: RTS

John

I have never heard so much details in such coherent manner before. There is so much depth on each musical notes. There are many perspectives.

I just list to Cello recording. Wow! I just went to listen to Maisky playing Cello live in HK 1 month ago and I can feel as though he arrived at my home. There are many layers of tonal color to be felt.

What did the extra two pods damage the sound?
I will call you when I develop more facts and feelings when I listen more.

Lam

From: AE <info@audioexotics.com>
Date: Saturday, October 30, 2010 at 8:59 AM
To: Dad <jstehno@comcast.net>
Subject: Re: RTS

Your rack is crazy!

From: AE <info@audioexotics.com>
Date: Saturday, October 30, 2010 at 8:45 AM
To: Dad <jstehno@comcast.net>
Subject: Re: RTS

John

Despite the imperfections, I am shocked by the improvement already! Very fast, smooth and details.....
​

Day 3

From: AE <info@audioexotics.com>
Date: Monday, November 1, 2010 at 6:45 AM
To: Dad <jstehno@comcast.net>
Subject: Re: Update

John,

I am really shocked by the performance of the rack on the 3rd day. I run out of words to describe it because the first day was already a revelation to me even though I carry SRA and also Critical Mass, which are already amongst some of the serious players out there.

I took up the two pods on the horizontal bar supporting the Zanden CDT as you suggested. The Zanden transport only sits on two pods now. The difference is very big! Immediately, I feel more body and more or everything. The improvement from your rack is not concentrated on one or few particularly areas but EVERYTHING. The most notable is the amount of harmonics/overtunes seems to come out in an exponential scale.

The PERFORMANCE of this rack is REVOLUTIONARY

With respect to develop it to a truly commercial high end product, I wish you can improve the following:

1. Paint job is good but definitely not at the level of SRA's OHIO XL+2 Platform. On close scrutiny, I can still see the raw texture underneath the orange color. But the orange is nice.

2. Everything received in good condition. I feel it will be more professional if you can pack on the BARS/Accessories under ONE big box with your company logo on.

3. The finish of the CLAMPING bars can be improved more; again I can see OK paint job on a raw metal.

4. The manual is very detailed with clear pictorial illustration. I think you can use picture to highlight the areas which demand excessive strength to tighten is even better.

5. Ease of assembling is not so difficult. I can see my man can do it much more quickly the 2nd time.

6. At the lowest section where the amplifier is sitting on, the distance between the two vertical rods and the FEMALE AC IEC of the amplifier (happens to be on the center position) is too short to use higher end power cord. Even though I tried hard to FORCE the power cable to bend, I can't get it through. I have to use more flexible power AC cable in this section.

I truly feel you have a revolutionary product here. If you want to win the hearts of even more, my sincere advice is to improve the cosmetics - the quality of paint. Try to take a look at the SRA OHIO XL+2 platform on the SRA website. Their paint job is noble, lacquered GLOSS with very BLACK Piano Black.

The above represents my honest comments. I am about to order another probably 2 to 3 level RTS (also orange color) for the Vekian transport and Vekian DAC (www.stahltek.com) from you soon once my cash position improves in the next 10 days. Go and take a look. I may just want a two level purely to single out this ultimate source components.

J.Lam​

On their website are some rather interesting comments including one saying my rack is their greatest find in recent years but I’m rather fond of this one:

"Dear Yamada, It is very very important to let you know. If you want to listen to the maximum performance of your Zanden system. Please come. No Doubt, it will be a new experience even for you--the inventor of Zanden. This orange thing is monster!! I am sure!”​

http://audioexotics.hk/forum/#/discussion/comment/8812

 

[KlausR.]

Jarek,

some thoughts:

So very quickly if there are reflections from the boundaries of materials, standing wave patterns appear and all looks like a complicated vibrating "drum".

On paper most probably, but what about the real thing: have such patterns been confirmed in housings of audio equipment, audio racks etc.?

Doppler vibrometers have been used to measure vibration in loudspeaker cabinets, so there’s a more than appropriate tool for examining e.g. amplifier housings or audio racks:

http://www.aes.org/e-lib/browse.cfm?elib=12234

But not impossible - I believe good tonearms achieve this, taking the energy away from the cartridge and dissipating in the bearings.

Cartridge bodies come in all shapes and colours, and of course in a variety of materials. The same is valid for tone arm headshells. How are the chances that you get a good impedance match? There are arm tubes with internal damping layers for dissipating energy, but with a serious impedance mismatch at the cartridge/headshell interface there is not a lot to dissipate. When arm tubes are from light metal alloys, wood, carbon fibre, and arm bearings from (hardened) steel, impedance mismatch is more than likely.

This brings to the two basic vibration control schools: Take away and dissipate somewhere or start dissipating immediately. First would be a stiff rack, with high resonant frequencies. IMO, this is the type of a rack is optimal for isolation platforms:
You want the resonant modes to be of the type and frequencies such that the platform will easily eat them.

Resonance in a receiver will only occur when the source emits frequencies which match the resonance frequencies of the receiver. For our case this means that not only you need a good impedance match between audio component and audio rack but that the resonance frequencies of component housing and audio rack match. How likely is that?

Klaus

 

[spiritofmusic]

No disrespect John, but tbh your offer of getting involved was really a bit of a tease, mirage at best, total waste of my time at worst
All I was saying was that in my investigations so far, Stacore was a likely contender to get my hard-earned
Jarek fully understands that his device is up against already established heavywt contenders in Minus K and Herzan, and didn't cry things off
If you really think I would buy into anything like yr concept and product w'out comparing it against anything else, you really didn't think it thru
You come online pretty much castigating other vibration management issues as being wrong headed, inferior, and that your's has amazing effects, boosting performance up the scale
As people like me show interest, you drop some clues as to yr approach, and then tell us you're not even in current manufacture
And as I show continued interest but inform you of the fact that my preference up to this point had been established brands (and a new one, Stacore), you bow out
Puh-lease!
Thank you SO much for volunteering not to waste my time further

 

[Stacore]

On paper most probably, but what about the real thing: have such patterns been confirmed in housings of audio equipment, audio racks etc.?

Doppler vibrometers have been used to measure vibration in loudspeaker cabinets, so there’s a more than appropriate tool for examining e.g. amplifier housings or audio racks:

http://www.aes.org/e-lib/browse.cfm?elib=12234

I'm not aware of any such tests unfortunately. This is the saddest paradox of our times: we have excellent technology, people would die for some decades ago when audio was still in active *scientific* research, but nobody uses it because....it doesn't pay off.

Cartridge bodies come in all shapes and colours, and of course in a variety of materials. The same is valid for tone arm headshells. How are the chances that you get a good impedance match? There are arm tubes with internal damping layers for dissipating energy, but with a serious impedance mismatch at the cartridge/headshell interface there is not a lot to dissipate.

I think you just rediscovered one of the serious reasons why some arm-carts combos do not sound good despite formal parametrs match (eff. mass +compliance)

When arm tubes are from light metal alloys, wood, carbon fibre, and arm bearings from (hardened) steel, impedance mismatch is more than likely.

...and thats why I personally do not use soft material tonearms

Resonance in a receiver will only occur when the source emits frequencies which match the resonance frequencies of the receiver. For our case this means that not only you need a good impedance match between audio component and audio rack but that the resonance frequencies of component housing and audio rack match. How likely is that?

Klaus

I actually answered that explaining why we used hammers and not music or pure tones: In real-life music you have complicated signal shapes, for example sharp attacks. They can contain a large spectrum of frequencies, so a good chance is some will match resonant modes of your gear...unfortunately

Cheers,

 

[KlausR.]

In both cases, that's shock and impact and has nothing directly to do with superior methods of managing much smaller vibrations that continuously bombard our sensitive components.

So you are talking airborne vibration here, in which case an isolation device will obviously not work, unless it’s a soundproof cabinet you put the gear in. And I presume you are also talking vibration generated within the component itself, such as coming from a transformer or vibrating coils (coil whine). However, transformers and coils can be decoupled and/or damped.

Same with air-borne vibrations captured at the chassis. Hence, this constant continuous bombardment of vibrations are trapped at the chassis with nowhere to go, hence their crippling affect.

And exactly for that I’d like to see some hard evidence: do parts of audio components vibrate when being exposed to airborne vibrations? The Doppler vibrometer will easily tell you. And if they do, does that have an effect on the sound? A controlled listening test will easily tell you.

1) As one committed 100% to mechanical energy transfer, I use hard rigid materials and designs only and all tightly coupled. Why would a true isolationist (is there any other kind?) use even a single piece of material that was harder or more rigid than say Sorbothane? And why would they have even one connection fastened tightly?

In cases where structural vibrations creeping up your rack into the turntable are the only source of vibration, isolating the TT is enough. Optical tables do just that. The allegation that airborne vibrations and vibration generated by the component itself are harmful still needs to be proven by hard evidence. So far I haven’t seen any.

2) If as the isolationist says, the floor-borne vibrations induce the most harm and that's what we need to protect our sensitive components from it, why do their solutions not follow their mindset?

During my college time I lived in an old house with wooden floor, the cartridge was jumping all over the place when I moved, so I provided cheap (DIY) but effective mechanical decoupling. Why other people do other things when confronted with the same problem, you should ask these other people.

Klaus

 

[Taiko Audio]

As I have some hands on experience with active isolation technology I'll try to provide some context.

So you are talking airborne vibration here, in which case an isolation device will obviously not work, unless it’s a soundproof cabinet you put the gear in. And I presume you are also talking vibration generated within the component itself, such as coming from a transformer or vibrating coils (coil whine). However, transformers and coils can be decoupled and/or damped.

You are partially correct here, for FULL isolation the isolation platform + component would need to be placed inside a soundproof booth. The loudspeakers will excite the floor and their transmitted airborne vibrations will excite the floor creating a nice mess, this however an active isolation platform can handle very well. The airborne vibrations will also excite the component itself through air (obviously). Here things get tricky. The more advanced platforms will provide corrective action to vibrations being emitted from the component moving it in counter phase. For this to work the component needs to be rigidly coupled to the isolation platform. Isolating footers (soft, ball bearing etc.), "decoupling" will A) prevent the sensors inside the isolation platform from correctly detecting the component vibrations, B) will alter corrective movement of the platform. If you want maximum performance out of an isolation platform you would probably be best off removing the component's footers entirely, if possible even bolt it on to the platform. As for as how any residual excitations are handled is up to the rigidness of the components housing.

And exactly for that I’d like to see some hard evidence: do parts of audio components vibrate when being exposed to airborne vibrations? The Doppler vibrometer will easily tell you. And if they do, does that have an effect on the sound? A controlled listening test will easily tell you.

As I'm in possession of 3-axis measuring equipment, a pair of subwoofers and an iPhone I can look into making a real-time (amateur) video recording of the effect of an active isolation platform. Would that help?

 

[KlausR.]

As I'm in possession of 3-axis measuring equipment, a pair of subwoofers and an iPhone I can look into making a real-time (amateur) video recording of the effect of an active isolation platform. Would that help?

You mean you have means to produce a graph or image of the vibrating housing of e.g. an amplifier housing when exposed to sound from a loudspeaker, the graph indicating amplitudes and frequencies?

What exactly is that 3-axis technique you mention?

Klaus

 

[spiritofmusic]

Hmm, I think I'll pass on bolting stuff to platforms
Not poss w my tt for a start
I think I'll stick for tt w inert bulletproof one-piece rack (Rogoz), add a passive mechanical spring-, or passive pneumatic springs-, or active piezo electric-platform to contend w flr- and air-borne vibrations, and Symposium Acoustics Quantum Signature constrained layer shelf to deal w tt-borne vibrations, in a : flr>Rogoz rack>active or passive platform>Quantum shelf>tt, configuration
A bit of a l/t project for me here

 

[Mike Lavigne]

Looks very professional indeed. However, I can't see anything relating to audio components. I further can't see anything relating to controlled listening tests. Further I don't think that mechanical decoupling is a solution for airborne sound.

So once again, where is the evidence that vibration in audio components is a problem?

why would audio components be any different than what is being targeted in those tutorials? it's not any different. follow the steps outlined. the tools offered in those tutorials are good enough for world class laboratories.

but I will allow Emile (Taiko) to explain.

 

[KlausR.]

I'm not aware of any such tests unfortunately. This is the saddest paradox of our times: we have excellent technology, people would die for some decades ago when audio was still in active *scientific* research, but nobody uses it because....it doesn't pay off.

The only company I know of that seriously is into scientific research is Harman (Sean Olive (succeeding Floyd Toole) and his team). Otherwise it would certainly pay off, but people generally don’t ask for proof and buy the stuff relying on what they hear, so why should companies bother? That’s fine with me, but for myself I use a different approach.

Originally Posted by KlausR.
Cartridge bodies come in all shapes and colours, and of course in a variety of materials. The same is valid for tone arm headshells. How are the chances that you get a good impedance match? There are arm tubes with internal damping layers for dissipating energy, but with a serious impedance mismatch at the cartridge/headshell interface there is not a lot to dissipate.

I think you just rediscovered one of the serious reasons why some arm-carts combos do not sound good despite formal parameters match (eff. mass +compliance)

It should have become obvious that I do not believe in results from sighted listening, which is what is done in 100% of the cases. So without controlled listening tests I have no reason to believe that some arm-cart combos sound bad indeed. But that’s me.

Originally Posted by KlausR.
When arm tubes are from light metal alloys, wood, carbon fibre, and arm bearings from (hardened) steel, impedance mismatch is more than likely.

...and thats why I personally do not use soft material tonearms

When I bought my current vinyl setup 18 years ago I had a good look in J. of the Audio Engineering Society, and of course Audio magazine with all the nice reviews by E.E. Long, and Shure, SME and Michell could convince me, purely from a technical point of view.

Originally Posted by KlausR.
Resonance in a receiver will only occur when the source emits frequencies which match the resonance frequencies of the receiver. For our case this means that not only you need a good impedance match between audio component and audio rack but that the resonance frequencies of component housing and audio rack match. How likely is that?

I actually answered that explaining why we used hammers and not music or pure tones: In real-life music you have complicated signal shapes, for example sharp attacks. They can contain a large spectrum of frequencies, so a good chance is some will match resonant modes of your gear...unfortunately

I wrote this in the context of “take away and dissipate” you mentioned, not in relation to the setup you use for testing your pneumatic platforms. To me take away means transmit the energy from the component into a drain, such as the rack, then dissipate further down the line. If you want to drain energy away from a component, by resonant energy transfer as you said, you need both matching impedances and matching eigenfrequencies of component and rack.

Klaus

 

[Taiko Audio]

You mean you have means to produce a graph or image of the vibrating housing of e.g. an amplifier housing when exposed to sound from a loudspeaker, the graph indicating amplitudes and frequencies?

What exactly is that 3-axis technique you mention?

Klaus

Yes exactly.

Vibrations excite an object in multiple directions, the 3 axis I can measure are vertical (height), horizontal 1 (depth), horizontal 2 (width).