Equipment isolation and vibration damping.

[YashN]

Tossing out Herbie's Audio Lab products for cost effective consideration.

 

[ATTACH=CONFIG]19274[/ATTACH]

 

 

He has fairly stalwart customers. I see his products mentioned quite a few times of forums.

[YashN]

Theories may sound nothing less than mind-blowing. Any comparison between practical solutions? Please no plastic egg-holders with wooden balls. Teflon? Until we are going to fry our brains.

 

Check the Waves 'The Truth' web page as linked to above: some cool info there, and perhaps Duke40, Barry and John can confirm if it matches their knowledge or practical experience.

[YashN]

John,

 

What does it sound like when you pluck one of them ?

 

Both when quiet and music playing ?

 

I was thinking about using nylon the other day, but not sure it's solid enough. In a live music environment we go to from time to time (very small stage), the speakers are suspended with metal chains. It sounds very good.

[YashN]

As to Teflon, it has a fairly low friction when mated with some materials, and very low "sticktion" with others. In all cases the friction is orders of magnitude more resistance than what you get from a hard ball rolling on a hard surface. A ball rolling on Teflon will have much more resistance than when rolling on a hard surface.

 

I remember seeing that term 'sticktion' in my recent reading sessions. It's new to me, never saw it before in Physics classes. Teflon is out then, if I'm understanding correctly.

[YashN]

Tonight in the mad scientist lab (click for the videos):

 

1. X, Y, Z + GYRO

 

https://drive.google.com/file/d/0B9VKnWFwKzxKdG5RVC1FcE1DM00/view?usp=sharing

 

2. X, Y, Z Graphs

 

https://drive.google.com/file/d/0B9VKnWFwKzxKdEVlOElNVWxSN3c/view?usp=sharing

 

Promising, I am using only spongy balls as first layer, and I'm fairly sure the inner tube will be a better air-cushion.

 

That upper layer, although it's only marbles, is fantastic!

[rocl444]

Unfortunately my understanding of Physics is severely limited and I have not been able to understand all the principles discussed here, but I have been thinking about the whole idea.

 

With the ball and bowl the amount of movement made by the ball is extremely small - right? Amost microscopic? So the amount of movement needed for the vertical plane would be about the same I'm guessing. So wouldn't having 3 springs in place of the ball and cup actually allow enough movement in both planes?

 

If so, 2 sheets of aluminium with springs attached to the bottom one would isolate a lot of vibration.

 

On another tack, some people use ply, especially birch, so how would that compare with aluminium acoustically? Then I could maybe think of placing my SF Cremona M's onto them.

[rocl444]

Part of my reticence regarding the ball and cup is based on my experiences in the earthquakes here a few years ago. Some stability is worthwhile in such events.

[AnotherSpin]

Now on to the promised tome on vertical isolation.

 

Horizontal isolation is fairly easy to achieve, a pendulum or good implementation of the ball between hard surface does a good job of isolation down to low single digit Hz range.

 

But how do you do something equivalent in the vertical direction? There is this massive DC bias (weight due to gravity) that you have to somehow overcome. This is not easy.

 

Several years ago I was trying figure what a vertical isolator would do, ignoring for a moment any practical implementation details. What I came up with is a system that is stiff at DC but highly flexible at AC. This is exactly opposite to things like Sorbothane which are stiff at AC but soft at DC. All the "vibration damping" systems I could find had it all backwards.

 

So I asked this question on an internet forum, what material has a high spring constant at DC, but a low spring constant at AC? I was given the answer of a Euler spring (pronounced "Oiler"). This is not a material but a way of using common materials in an unusual way. It turns out it doesn't distinguish between DC and AC per se, but is a HIGHLY non-linear spring. As you increase the force on it the spring constant is extremely high, until you get to a specific threshold, then it transitions into a very low spring constant. This is EXACTLY what we want for vertical isolation. The system is set so the weight of what is being isolated just puts the Euler spring over the threshold into the very low spring constant range. Once you achieve this a very small force causes a large displacement, exactly the same thing as happens in the horizontal mode with the ball and shallow bowl.

 

So what IS a Euler spring? It is a rod or bar of material with the load applied right down the axis. It can be made out of many different materials, steel, brass, carbon fiber, all kinds of stuff. The trick is to arrange things so all the load is perfectly in line with the main axis, ie there is no "bending" force. In the literature this is commonly referred to as the "column". As the force on the column increases nothing happens at first, the material is basically incompressible. BUT at some point something gives, the column "buckles", it bends even though there is no "bending force" applied. This is the special zone. Now a small change in force causes a large increase in the buckling, causing a large displacement.

 

Most people will immediately think of several things wrong with this. First is "that has got to take a LOT of force to cause that to happen" maybe thousands of pounds. For a thick column, quite true. But it doesn't have to thick, take a very thin bar or rod and the buckling can start at very low forces. Then the next thought is, well it will just fall over! Yep, in order for this to work properly the column has to be constrained so the force is always applied completely axially to the column. Making a supporting structure that doesn't interfere with the basic operating principles has been one of the tough challenges with using Euler springs in actual useful situations.

 

The traditional implementation has been a pair of thin bars of metal (say an inch wide and very thin) constrained in such a way that when they start buckling they bulge out away from each other. This helps a lot with the stability, but is still pretty unstable and requires considerably more support structure. A common support is the top of each bar is connected to a long horizontal arm with a hinge at the other end. This keeps things in place and doesn't interfere too much with the operation of the spring. But it is large and cumbersome, not something you would want in your stereo system.

 

Recently (in the last couple years) a new configuration of a Euler spring has been invented which I personally think is going to revolutionize the whole concept of Euler springs and make them applicable to a much wider range of uses. This is the tetrahedral Euler spring. If you are not familiar with a tetrahedron it is essentially a three sided pyramid. The tetrahedron has four sides (a cube has 6), one as the base and three that make up the "sides" of the pyramid.

 

Think of a tetrahedron made out of very thin carbon fiber rods. Take such a structure and place one side on the ground, pointing up is a "point" of the tetrahedron. Now take three of these and place a platform on top of the three "points". It is a nice stable platform. Now start putting weight on the platform. At first nothing happens, but then as you reach the "critical force" the rods in the tetrahedrons start to buckle and the whole platform moves down an inch or so. Now a very small force applied to the platform causes it to move down. Because of the tetrahedral configuration the platform is stable, it doesn't "fall over" or wander all over the place, it just moves up and down. If you get the length and thickness of the rods right you can make the resonant frequency of the system quite low (sub hertz).

 

Now on top of the platform put the shallow bowl and ball bearing we have been talking about and you have a VERRY effective isolation system that works down to the low single digit Hertz range.

 

This generally tends to work better with longer rods, so I came up with a rack with six foot high tetrahedrons, from which are suspended strings holding up a shelf, so the system uses Euler springs for vertical and pendulum for horizontal. It would certainly be a conversation piece in your listening room! You could use these for speakers as well as equipment.

 

Note I have not built a tetrahedral Euler spring yet, my clients keep me too busy designing stuff for them.

 

I have done the traditional "leaf spring" version. These are really weird feeling things, you press down hard then it reaches the threshold and all of the sudden it is "squishy", it is a very bizarre feeling, there is nothing else in your experience that feels this way.

 

BTW the person that invented the tetrahedral Euler spring used them as a protection system for drones. A far cry from stereo systems.

 

John S.

 

John, very insightful reading. What we could try to do in a real world of cheap materials and limited budget with vertical isolation? As an alternative to bicycle tires? Would you share any pictures of your isolation solutions? Thank you.

[bdiament]

Part of my reticence regarding the ball and cup is based on my experiences in the earthquakes here a few years ago. Some stability is worthwhile in such events.

 

Hi rocl444,

 

It might be interesting to note that the ball-in-bowl idea originated close to a century ago for the purpose of isolating tall buildings in earthquake prone places.

 

With regard to the spring idea you mentioned, in my experience, the easier it is to move the isolator--in the plane in which it is to isolate--the more effective it will be. So the question becomes, will those springs be as easy to move horizontally as a ball in a shallow bowl?

And of course, will they be as "loose" vertically as a minimally inflated, thin-walled inner tube?

 

Also, will they *continue* to move as long as the ball will horizontally and the inner tube will vertically?

If there is parity, I'd say they're a good idea.

 

An effective mechanical low-pass filter (which is the function for which these things are being used) will move very easily and very slowly (lowest resonant frequency), and will continue moving for a long time (minimal damping).

 

Best regards,

Barry

Soundkeeper Recordings

http://www.soundkeeperrecordings.wordpress.com

Barry Diament Audio

[YashN]

Unfortunately my understanding of Physics is severely limited and I have not been able to understand all the principles discussed here, but I have been thinking about the whole idea.

 

That's not a problem at all. In fact, so far we have managed to avoid posting equations

 

I think the most difficult thing isn't understanding the phenomena and what works better than other things as per Physics. The most difficult thing is keeping an open mind and not sticking to known principles which are well-tested for other applications but aren't suited for audio.

 

There are many examples of taking things for granted with digital audio, but if you delve deep enough, there are issues and specifics to digital audiophilia. Finding those specifics is key.

 

 

With the ball and bowl the amount of movement made by the ball is extremely small - right? Amost microscopic?

 

In normal un-handled use, yes.

 

So the amount of movement needed for the vertical plane would be about the same I'm guessing. So wouldn't having 3 springs in place of the ball and cup actually allow enough movement in both planes?

 

If you check Towshend's new isolators, he implements using spring and rubber or something similar. There also exists an HRS nimbus one which is a single spring arrangement. I believe the thing to take into account if you are using more than one spring is to ensure their combined effect still has the lowest frequency possible.

 

If you look at the theory in Physics, the model often use is precisely that of a mass attached to a spring, and sometimes with an additional damping apparatus.

 

The Minus K platform also use at least one spring.

 

So springs are a definite possibility, as are other geometries that act like one.

 

On another tack, some people use ply, especially birch, so how would that compare with aluminium acoustically?

 

Acoustically, many like wood because traditional musical instruments have a resonant body made of wood, so wood doesn't sound out of place if it resonates. On the other hand, ideally, you would want the most inert platform possible. John Swenson wrote at length about the advantages of aluminium above.

[YashN]

Several years ago I was trying figure what a vertical isolator would do, ignoring for a moment any practical implementation details. What I came up with is a system that is stiff at DC but highly flexible at AC. This is exactly opposite to things like Sorbothane which are stiff at AC but soft at DC. All the "vibration damping" systems I could find had it all backwards.

 

Thoroughly interesting, John.

 

So what IS a Euler spring? It is a rod or bar of material with the load applied right down the axis. It can be made out of many different materials, steel, brass, carbon fiber, all kinds of stuff. The trick is to arrange things so all the load is perfectly in line with the main axis, ie there is no "bending" force. In the literature this is commonly referred to as the "column". As the force on the column increases nothing happens at first, the material is basically incompressible. BUT at some point something gives, the column "buckles", it bends even though there is no "bending force" applied. This is the special zone. Now a small change in force causes a large increase in the buckling, causing a large displacement.

 

On first read, this reminded me of the beams in the Minus K, but in fact, Minus K uses beams and a beam-column effect so that it acts as a spring + negative-stiffness device for the horizontal plane isolation.

 

Thus it is quite intriguing that we could use beams for both vertical and horizontal isolation.

 

 

Think of a tetrahedron made out of very thin carbon fiber rods.

 

By this, do you mean the vertices are each made of one rod, or some other geometric constitution?

 

BTW the person that invented the tetrahedral Euler spring used them as a protection system for drones. A far cry from stereo systems.

 

I have seen some cool isolation devices for stabilising images from digital cameras as well, like the GoPros, and other for drones, and then people also mount their GoPros on their drones...

[Foggie]

Now on to the promised tome on vertical isolation.

 

Horizontal isolation is fairly easy to achieve, a pendulum or good implementation of the ball between hard surface does a good job of isolation down to low single digit Hz range.

 

But how do you do something equivalent in the vertical direction? There is this massive DC bias (weight due to gravity) that you have to somehow overcome. This is not easy.

 

Several years ago I was trying figure what a vertical isolator would do, ignoring for a moment any practical implementation details. What I came up with is a system that is stiff at DC but highly flexible at AC. This is exactly opposite to things like Sorbothane which are stiff at AC but soft at DC. All the "vibration damping" systems I could find had it all backwards.

 

So I asked this question on an internet forum, what material has a high spring constant at DC, but a low spring constant at AC? I was given the answer of a Euler spring (pronounced "Oiler"). This is not a material but a way of using common materials in an unusual way. It turns out it doesn't distinguish between DC and AC per se, but is a HIGHLY non-linear spring. As you increase the force on it the spring constant is extremely high, until you get to a specific threshold, then it transitions into a very low spring constant. This is EXACTLY what we want for vertical isolation. The system is set so the weight of what is being isolated just puts the Euler spring over the threshold into the very low spring constant range. Once you achieve this a very small force causes a large displacement, exactly the same thing as happens in the horizontal mode with the ball and shallow bowl.

 

So what IS a Euler spring? It is a rod or bar of material with the load applied right down the axis. It can be made out of many different materials, steel, brass, carbon fiber, all kinds of stuff. The trick is to arrange things so all the load is perfectly in line with the main axis, ie there is no "bending" force. In the literature this is commonly referred to as the "column". As the force on the column increases nothing happens at first, the material is basically incompressible. BUT at some point something gives, the column "buckles", it bends even though there is no "bending force" applied. This is the special zone. Now a small change in force causes a large increase in the buckling, causing a large displacement.

 

Most people will immediately think of several things wrong with this. First is "that has got to take a LOT of force to cause that to happen" maybe thousands of pounds. For a thick column, quite true. But it doesn't have to thick, take a very thin bar or rod and the buckling can start at very low forces. Then the next thought is, well it will just fall over! Yep, in order for this to work properly the column has to be constrained so the force is always applied completely axially to the column. Making a supporting structure that doesn't interfere with the basic operating principles has been one of the tough challenges with using Euler springs in actual useful situations.

 

The traditional implementation has been a pair of thin bars of metal (say an inch wide and very thin) constrained in such a way that when they start buckling they bulge out away from each other. This helps a lot with the stability, but is still pretty unstable and requires considerably more support structure. A common support is the top of each bar is connected to a long horizontal arm with a hinge at the other end. This keeps things in place and doesn't interfere too much with the operation of the spring. But it is large and cumbersome, not something you would want in your stereo system.

 

Recently (in the last couple years) a new configuration of a Euler spring has been invented which I personally think is going to revolutionize the whole concept of Euler springs and make them applicable to a much wider range of uses. This is the tetrahedral Euler spring. If you are not familiar with a tetrahedron it is essentially a three sided pyramid. The tetrahedron has four sides (a cube has 6), one as the base and three that make up the "sides" of the pyramid.

 

Think of a tetrahedron made out of very thin carbon fiber rods. Take such a structure and place one side on the ground, pointing up is a "point" of the tetrahedron. Now take three of these and place a platform on top of the three "points". It is a nice stable platform. Now start putting weight on the platform. At first nothing happens, but then as you reach the "critical force" the rods in the tetrahedrons start to buckle and the whole platform moves down an inch or so. Now a very small force applied to the platform causes it to move down. Because of the tetrahedral configuration the platform is stable, it doesn't "fall over" or wander all over the place, it just moves up and down. If you get the length and thickness of the rods right you can make the resonant frequency of the system quite low (sub hertz).

 

Now on top of the platform put the shallow bowl and ball bearing we have been talking about and you have a VERRY effective isolation system that works down to the low single digit Hertz range.

 

This generally tends to work better with longer rods, so I came up with a rack with six foot high tetrahedrons, from which are suspended strings holding up a shelf, so the system uses Euler springs for vertical and pendulum for horizontal. It would certainly be a conversation piece in your listening room! You could use these for speakers as well as equipment.

 

Note I have not built a tetrahedral Euler spring yet, my clients keep me too busy designing stuff for them.

 

I have done the traditional "leaf spring" version. These are really weird feeling things, you press down hard then it reaches the threshold and all of the sudden it is "squishy", it is a very bizarre feeling, there is nothing else in your experience that feels this way.

 

BTW the person that invented the tetrahedral Euler spring used them as a protection system for drones. A far cry from stereo systems.

 

John S.

 

Funny, I sent this to one of the lead ME's at work about this topic the other day - just an interesting video. Listen for the "snap"

 

 

Sent from CA app

[Duke40]

I remember seeing that term 'sticktion' in my recent reading sessions. It's new to me, never saw it before in Physics classes. Teflon is out then, if I'm understanding correctly.

 

Requisitioned my gf's pancake pan while she was not looking, rested 3 good-sounding marbles on it and balanced a bamboo plate on it: now, THAT'S free motion!

 

 

 

hi YashN … a lot of good stuff in this thread.

 

 

7 years ago I also took my GF’s pancake tray, used some marbles & bamboo !!!

You are not alone in trying these experiments.

Good times.

 

 

Re-reading this thread to try to come up to speed. Some stuff will echo that of others, some may conflict, some may be new thoughts … but afterall this is just my opinion.

 

 

Plus most of my experimentation was between 2005 and 2010 … so I am a bit rusty on this topic. I actually did night school at university (first year physics) back in 2010 to understand the “why” of things in relation to audio … like sound waves, power & energy (mechanical, kinetic)… but the more I learn … the more I realise I don’t know. During lecture breaks my Physics professor must have thought “Oh no … here comes the audiophile!” when I approached him.

 

 

Anyway, I will add to my isolation/resonance “journey” or tale of “Audiophile gone wild”.

 

 

Still .. Post 3 in this thread by Barry Diament… and post by John Swenson on ALU stand out the most to me.

 

 

Afterall it was Barry’s “Vibration control for better performance” that became my template and reference for the start of my experiments … I also thought it was quite brave & courageous to write an article like that … the benefits of isolation were less well known than they are today. Then again, who dares … wins. I had started research on Audiogon … yet it was not until I read “Vibration control for better performance” that I had a great & inexpensive base for experimenting. Also intriguing to hear John Swenson thoughts on ALU … I have heard remarks from other audio designers (like the guy from Arcam), though really never understood fully the technical “why” of why I like ALU … I just trust my ears (as well as some effort on learning this topic … plus experimenting).

 

 

 

 

Statements like below, echo my thoughts … I could not be that eloquent.

 

 

“Now, what I've learned in my own experiments is that just about anything you put under (or atop) a component will change its sound. The operative word is "change" which should not be confused with "improve." Couplers like spikes and cones *will* change the sound but what I've found is the change is somewhat random and inconsistent from component to component. These are ideal for folks who want to play with the "color" of their components. But they aren't the same as isolating a component and freeing it to do what(ever) it can do. (By the way, in my view, the idea of an "isolation cone" is an oxymoron, like "jumbo shrimp" or "civil war.")"

 

 

 

Below is a photo of some things I have tried as footers...

 

 

 

Apart from the bicycle tube … everything listed below seem to alter the sound , not always in a positive way. “Wasted” or “Invested in experimenting” about $400 on the stuff mentioned below (plus the different platform materials mentioned at the end of this long post).

 

 

Blu-Tak … under speakers … smeared the sound

Sand Filled Box’s … under components … not much effect

Brass Cone …. lasted a week

Ceramic Cone …. dry

Ebony Wood Cone … wood seems to focus on the mid-rage

ALU cone … (I always mistype Aluminum, so just abbreviate it to ALU)

1/2 Squash Balls

Full Squash Balls …. red dot, yellow dot

Sorbathane … various thickness … smears sound … may as well throw a rug over my speakers

Acryllic … various thickness … not for me … maybe I did not try the right combo with platform material

Marbles … liked the effect, saw the potential, which I was I got the Nordost Quasar Points mentioned later.

 

 

Things I did not try ;

$1K Carbon Fibre shelves

Expensive “Racing” Cones

Titanium … or anything else which was "Unobtanium"

Laboratory Isolation Platforms

 

 

I also tried putting a spring inside some sort of rubber material … trying to echo my Townshend Springs … but it was just not stable … or good.

 

 

Not shown is Nordost Pulsar Points. Just OK (even if it made out of ALU).

Thins sound out a bit.

 

 

Also tried Nordost Quasar (?) Points … 2 piece of ALU with a roller ball bearing in the middle.

That was the most effective of everything listed above (reminded me of the marbles , though a bit better)… now I was getting somewhere. Still, I liked the Bicycle tube.

 

 

Though I did find combing them provided cumalative benefits.

That is;

Nordost Quasar points on hifi rack shelf

Some type of shelf material

Bicycle Tube

Another layer of shelf material

DAC

 

 

Well, the above is still kind of following BD’s recipe (the benchmark for starting my experiments).

 

 

At that time I also found I that I preferred no Footers … at all.

So I removed the footers from my equipment … and rested thing like DAC, CD players, PS3 on plates of 10mm ALU.

See photo ...

 

 

So my final favourite items to place between ALU plates ... ended up being very inexpensive (the $1 Steel Sand filled Door Stops with rubber base) or pricey (the Townshend Springs or Pods).

A better photo below...

 

 

 

Another thing …. Sand … 50 lbs (can not remember exactly) in my steel/glass hifi racks, stopped the steel ringing.

 

 

 

 

Oh … another thing I tried was an ALU piece called the “Eichmann Resonance Topper"

Above or below equipment I could not detect any benefit.

On top of speakers …. I noticed a very slight focussing of sound … not worth the money though for that application.

Finally I re read the instructions on the back … and it suggests sticking them to your windows … and this is when I really noticed a worthwhile benefit. Stuck a Topper into the very corner of window … so 4 Toppers per window in my listening rooms. This seemed to help nicely with airborne vibration.

See photo below.

 

 

 

Then I got the thought … maybe some rubber window seals … and applied these to all sliding windows in the house.

See photo below.

 

 

It dropped the sound coming into the house by a few decibel … also prevented sound of my speaker rig escaping by a few decibel.

 

 

… mmm, what else ….

 

 

 

 

I like placing ALU on top of components if possible …. as well as directly under (with no footer. Made a nice improvement to my BenchMark DAC1 Pre. It is difficult to see but I have 10mm plate of ALU on top of the Benchmark DAC1 Pre, very beneficial)

See photo below..

 

 

Photo is a bit old (no longer have the PS3 replaced it with an Oppo BDP-103).

 

 

Photo below is more recent … I have the ALU above and below the Oppo BDP-103.

Though most of my experimentations ended back in 2010 … I still play around determining how much effect on each component.

 

 

 

Oh, nearly forgot … the one thing I have found little benefit for isolating is my Isolation Transformers and Balanced Power Supplies (similar to what EquiTech make in the USA).

They weight 40 to 60 lbs … some of them can be seen in the above photo … they sound best when not on the floor …. so have put them on my headphone rack … tested placing them on isolation platforms … but for some reason I do not like it …. do not know why … they have huge transformers in them (hence the weight) … I placed a sheet of ALU underneath them (10mm thick) and they appear to like that … rather than being directly on the glass shelves of my headphone rack.

 

 

 

 

After Speakers … I still find the DAC the most sensitive … though I am experimenting still … so my Townshend Springs, $1 Door Stops and ALU plates tend to move around … currently trying to work out … if a double layer of springs is better under DAC … or have 1 set under DAC, another under the Oppo.

 

Below are some photo’s from a few months ago … if I tried this in the Living Room (instead of the Man Cave) I think my GF would kill me. My current project is how far I can improve a lifestyle product like my Auralic Gemini 2000 DAC/Headphone Amp … using Isolation techniques … better Linear Power … and better USB (USB Regen). Looks weird, but I am chuffed at the SQ result.

Photos ... hopefully these have better lighting than the previous one's ... I am not good at taking photo's

 

 

 

As of today … My current DIY reference stands… is using 2 sets or layers of springs … I think I am getting the right amount of both vertical & horizontal isolation… the right amount of “Float”.

 

 

Trying 3 sets of springs currently under my DAC … but not hearing anymore benefit.

 

 

Nearly forgot … by the way, I also tested a number of materials for platforms, but this post is already becoming “War & Peace”, that is a long novel.

So briefly ...

Acryllic … 5, 10, 20, 25 mm thickness … not a fan, seem to remove some energy out of music … I had hoped better results for Acryllic as it is used in some Turntable designs … maybe I had the wrong quality/thickness. This result surprised me. Then again I could be completely wrong about this material.

Granite slab…. no good … rings

Marble slab 20mm thick … good … 25mm better … 30mm best

American Maple … nice but not great

Bamboo … liked it a bit better than maple

Glass 10mm safety shatterproof … like those on my hifi rack's … not good … should replace them with shelves of ALU.

 

 

 

ALU 10mm plates … best material I have found so far … for platform shelves.

 

 

 

 

My findings are just that … my experience … if other’s have found different experiences, that is great too (like with different materials) … excellent !!! …. I am glad you advanced your setup so you can get even more enjoyment out of music … I am not out to diminish anyone else’s experience , beliefs or fun … my thoughts should only be taken as one data point … of just one guy experimenting (who is not an audio professional or engineer). Plus I could wrong, it certainly would not be the first time.

 

 

Anyway, I love Music and the Audio equipment aspect is just a hobby for me, and shall remain fun … plus like everyone else who is contributing to this thread … there definitely seems to be benefits in exploring this area of isolation/resonance.

 

 

So much great information just on the first page of this thread … though I think I will go back to researching what all the fuss is about OXCO Clocks and determining if I need them. Time for me to be confused in another area

 

 

I do not post much.

YahsN, I hope you get something out of my experience, It was a bit of fun experimenting.

 

 

John

[ted_b]

I use nothing but Sistrum stands, racks and speaker platforms. They are a commitment, though...they require you to be "all in" (sorry Cavs) and to never put any sort of secondary damper or vibration unit in the path of the energy. They also require some special attention if one is using a loaned piece of equipment (and me as a reviewer and equipment junkie have plenty of those situations), as the Sistrum racks use upturned audio points, so whenever you have equipment that you need to protect the bottom plate, use their spacers/protectors...which have nicely engineered cavities where the points couple up with.

 

Sistrums simple yet very effective idea is to use Coulumbs friction; that is, to let your audio pieces vibrate into the audio points they sit on, then provide a vehicle for easy and unencumbered energy flow, to ground. The concept works extremely effectively.

[AnotherSpin]

 

 

So my final favourite items to place between ALU plates ... ended up being very inexpensive (the $1 Steel Sand filled Door Stops with rubber base) or pricey (the Townshend Springs or Pods).

A better photo below...

[ATTACH=CONFIG]19305[/ATTACH]

 

 

 

 

 

Hi John, what type of sand you prefer? Whiteheaven silica?

[ted_b]

Hi John, what type of sand you prefer? Whiteheaven silica?

 

You just don't care, do you?

[Jabs1542]

You just don't care, do you?

 

I checked them out, they look very rigid which is what they are after. How do you determine where the spikes connect/touch your components? The front two look easy, unscrew the rubber foot and let the spike touch there (yes?), but the rear is in the middle which might be touching a weak aluminum casing bridge under the chassis.

 

BTW - My rack uses spikes to the floor with aluminum shelves and the uprights are filled with sand, and I use Stillpoint for the components. The concepts are similar to yours.

 

I am curious about the three points of contact.

 

Always curious if someone else figured out a better mouse trap...

[elcorso]

Hi John, what type of sand you prefer? Whiteheaven silica?

 

Silica sand is not good, at least you like a dull SQ.

 

Clean (no mud) river sand is the best.

 

Roch

[ted_b]

I checked them out, they look very rigid which is what they are after. How do you determine where the spikes connect/touch your components? The front two look easy, unscrew the rubber foot and let the spike touch there (yes?), but the rear is in the middle which might be touching a weak aluminum casing bridge under the chassis.

 

BTW - My rack uses spikes to the floor with aluminum shelves and the uprights are filled with sand, and I use Stillpoint for the components. The concepts are similar to yours.

 

I am curious about the three points of contact.

 

Always curious if someone else figured out a better mouse trap...

 

I place the equipment on the tripod (3 cones) so it balances and is NOT in a hole made by rubber feet, etc. You want it on the flat surface so it conducts energy as well as possible. The cones/tips are all adjustable for position.

[AnotherSpin]

You just don't care, do you?

I do care. About any practical solution that might be useful for those who care. What I do not care is words about words.

[InfernoSTi]

 

The "bowls" do not have to be large, just a shallow curve, in actual operation the distance things actually move is tiny so large bowls are not necessary. A good compromise seems to be a shallow surface with a rim, in normal operation the ball sits in the center and is moving microns at a time. The rim takes care of the situation where you push a button or try and pull a cable off etc, it keeps the device from moving very far. In normal operation it is not touching the rim.

 

I was thinking about commercial items that could be used for the "bowls" that would work well and are inexpensive. What I came up with are concave optical mirrors made of glass, they are hard, have highly accurate surfaces and highly polished. At first thought I thought they would be too expensive, but I found several places on Amazon that are selling concave glass mirrors in the 35-50mm diameter sizes for $2-$3 each. You can get focal lengths from 50mm to 250mm to try different "steepness" of curves. I haven't tried these yet but I'm planning on getting several and giving them a try.

 

By all means try them. I'd be curious as to what you find.

I'd be wary though of performance with heavy components simply because my experience as an amateur astronomer has taught me that glass flexes.

 

I found these on Amazon...just copy/paste this into the search function. They are $25 after shipping but that is for ten, enough for two sets of 4 or three sets of 3.

 

Imperial 6962 Concave Style Freeze Plug 1-5/8", Zinc Plated (Pack of 10)

 

 

I don't know if they would be smooth enough. Perhaps they could be polished? The main issue was that they are not glass. Thoughts?

 

Also, Ebay has inexpensive aluminum plates available in every size and thickness we would want. Also they have every size of metal ball bearings. Pretty good prices if you look a little.

 

John K

[Sam Lord]

Sorry all, I haven't read the entire thread so what I copy below might be fully redundant. I must add that I always find Barry Diament's posts illuminating and accurate. Anyway for everyone's benefit (so I claim), I keep emphasizing in the periodic (pun intended) threads on loudspeaker vibration one critical principle:

 

Separate *momentum* problems from *energy* problems until you have fully described each.

 

Here's a post I wrote last year to explain how bearings improve loudspeaker behavior. On re-reading I see some problems with the post, but I hope it helps. Thanks to John Swenson for his quoted passage.

 

Cheers, Sam

 

From post 152 in:

 

http://www.computeraudiophile.com/f8-general-forum/equipment-rack-and-isolation-suggestion-16048/

 

-------------

 

09-25-2014,*03:46 AM #152

Sam Lord

 

----

 Originally Posted by JohnSwenson 

 

"This handles the horizontal components of the seismic noise, but does nothing for the vertical components. The requirements for the vertical direction are much more difficult to deal with because of the DC bias (gravity). What you want is a system that has a very high spring constant for DC but a very low constant for AC, down into the sub Hertz range. Such systems are extremely difficult to come up with. Things such as elestomers are exactly the opposite of what you want, they have low constant at DC and high constant at AC. The approach of the partially inflated inner tube is better than most attempts, but still doesn't come close to what is really needed."

----

 

That was a great explanation and should be made a sticky. We should emphasize that we need only use basic physics to reduce the acceleration of components (except for loudspeaker diaphragms!). So many devices sold, like woodblocks and pucks, are merely replacing one spring with another, when we need to eliminate springs or at least use only springs with very low resonant frequencies.

 

We need to remind everyone that momentum is conserved: it can't be stopped or redirected, it can only be slowed by a high mass ratio, or in the oscillating case, by mechanical conversion to a different frequency. Fortunately energy, being a scalar (i.e. directionless), can be converted from one type of motion to another such as heat. It helps to understand the benefit of bearings when one considers that normal equipment feet are springs. They can convert energy but usually have too high a resonant frequency when loaded to help with horizontal or vertical vibrations. Bearings replace those multiple springs to act as a single, omnidirectional spring, acting only in the horizontal plane, with a long period that is usually symmetrical in every direction within the plane.

 

It seems that very troublesome vertical momentum can be effectively mitigated with a pendular approach as you described. Some fancy camera stabilizers work in a similar way. I believe a combination of brute-force measures like high-mass construction can be combined with vertical nonlinear springs and horizontal summers (i.e. smooth bearings on smooth, barely concave surfaces) to solve most vibration problems at the lowest total cost.

 

-----------

[AnotherSpin]

I must add that I always find Barry Diament's posts illuminating and accurate.

+1. Very practical, simple and working ideas. No bullshit from school study-books.

[YashN]

hi YashN … a lot of good stuff in this thread.

 

Blu-Tak … under speakers … smeared the sound

Sand Filled Box’s … under components … not much effect

Brass Cone …. lasted a week

Ceramic Cone …. dry

Ebony Wood Cone … wood seems to focus on the mid-rage

ALU cone … (I always mistype Aluminum, so just abbreviate it to ALU)

1/2 Squash Balls

Full Squash Balls …. red dot, yellow dot

Sorbathane … various thickness … smears sound … may as well throw a rug over my speakers

Acryllic … various thickness … not for me … maybe I did not try the right combo with platform material

Marbles … liked the effect, saw the potential, which I was I got the Nordost Quasar Points mentioned later.

 

Thanks, that's very useful.

 

The thing with acrylic is that it's used in vinyl systems because it is a good match-up with mats or vinyl (can't remember which). Not sure it's a good thing for what we envision.

 

I also tried putting a spring inside some sort of rubber material … trying to echo my Townshend Springs … but it was just not stable … or good.

 

This kind of device is used in ships for vibration control, so perhaps Townshend found a way to tweak them for audio use specifically, like the tension in the rubber and the type of spring.

 

 

I like placing ALU on top of components if possible …. as well as directly under (with no footer. Made a nice improvement to my BenchMark DAC1 Pre. It is difficult to see but I have 10mm plate of ALU on top of the Benchmark DAC1 Pre, very beneficial)

 

On top, you probably gain by further diminishing vibrations coming through the top plate, and perhaps some shielding as well. Must ensure your component's aeration vents aren't being obstructed though.

 

Oh, nearly forgot … the one thing I have found little benefit for isolating is my Isolation Transformers and Balanced Power Supplies (similar to what EquiTech make in the USA).

 

That's interesting: you would have thought they would. Just only recently been looking at those (reading about them mostly).

 

Below are some photo’s from a few months ago … if I tried this in the Living Room (instead of the Man Cave) I think my GF would kill me. My current project is how far I can improve a lifestyle product like my Auralic Gemini 2000 DAC/Headphone Amp … using Isolation techniques … better Linear Power … and better USB (USB Regen). Looks weird, but I am chuffed at the SQ result.

 

Cool that you can experiment in your space.

 

I had the same goal: see what I can optimise within limited means. It sounds great. Today a friend visited as I had repaired one of his synths. Made him listen to my system with the Totem Mites. After the music stopped, I told him: "My subwoofer isn't even on."

 

'I don't understand this! These speakers are playing like that!?'

 

LOL!

[YashN]

I use nothing but Sistrum stands, racks and speaker platforms. They are a commitment, though...they require you to be "all in"

 

Hadn't looked at them in detail before. Thanks Ted.