Equipment isolation and vibration damping.

[bdiament]

I have read the whole thread, and lot of people have given lot of very important feedback, thank you all for that.

 

I have a question before I implement this to my system. I know it is very cost effective arrangement, but is it better in performance compared to few other systems like Stillpoints; which I don't understand how it works, but that is what they claim. Why I am asking is also because I am little afraid that things might tend to slide off or not really be stable (I have lot of money invested in the gear). So question really is; how is the experience with stability (say a heavy amp), and how this arrangement compares to other commercial offerings.

 

Do things tend to slide off, say due to change in air pressure in the tube because a valve leaked or something.

 

Thanks again.

 

Hi sig8,

 

I have never had any issues with things sliding off roller bearings or air bearings. That said, I have always offered a few caveats:

 

1. If a remote control is not used, one must develop a gentle touch on front panel controls. Stabilizing a component with one hand while operating the controls with the other works. I've also found that I can use a few fingers to stabilize a component and press a button with the thumb on the same hand. Or just be gentle with a normal button push. The component will jiggle but that is simply an indication that the isolation is working.

 

2. One must be mindful of some pets, small children, and guests in the listening room. My cats and large dog have often visited the studio/listening room and luckily, I've had no issues at all. I routinely warn first-time guests to stay clear of the speakers. (A quick visual demo where I show them the speakers will move easily is always sufficient.)

 

3. Changing air pressure in an air bearing usually requires one disconnect the component, remove it, remove the platform, change the inflation, restore the platform, restore the component, and reconnect. Flexible valve extensions can be used to avoid all this, allowing inflation adjustment while the music is playing (!).

 

One thing to keep in mind is that most of the commercial products involve more damping on the ability of the isolator to move. This makes things less "jiggly" and it also means there is appreciably *less* isolation. (Greater damping = slower rolloff above resonance = less isolation.) The best, most effective isolators will theoretically be like having the components supported by Jello on springs. ;-} In practice, even with minimal damping, things are much more stable than that. There is still a sense of the Jello but as long as nobody (or nothing) crashes into the gear, all has been completely fine in my experience.

 

Best regards,

Barry

Soundkeeper Recordings

http://www.soundkeeperrecordings.wordpress.com

Barry Diament Audio

[Daudio]

This is why I use the Symposium Jr HD roller balls under my very large speakers. First, they thread with a 1/4-20 thread. Second, they are two halves rather than open on the top. While that isn't as "perfect" as open on top, it is much, much more stable. I am very happy with the results and find them to be completely stable even though the "wiggle" when bumped. They really can't tip over with the design.

 

John,

 

What is your experience with a 'triangular' support under your large speakers with the Jr's ?

 

I use 4 'open-topped' rollers under my big speakers for stability and load capacity. I have been using 3 similar devices under my subs, and find it too easy to reach out for support to one of the corners of the woofer box that doesn't have a device under it, and tipping it over. I may go to 4 devices per woofer too, just for a reasonable amount of stability.

 

I'd consider the 'double stack' arrangement, like the Jr's, but my acrylic bowls have a deep curvature, and I'm wary of too much impedance with two deep bowls (and corresponding larger ball). I have a couple of sets of devices in a double stack arrangement for some lesser equipment, and while they are very stable and easy to setup, but I don't like the feel of them - too stiff.

 

My preference would be to get some blocks with a very shallow curvature and the smallest balls that would work with top and bottom bowls. I think that would be a good compromise between stability and performance.

[YashN]

I was playing with different types of bamboo boards, from cheapest to expensive Japanese imports. Most expensive from them are quite thick, and they add to sound characteristics rather than isolate. The idea is everything what we use to support components needs to be neutral, is bamboo neutral?

 

There are a few things to consider:

 

You'd rather use something like metal for the surface in contact with the ball.

 

The bamboo item can be constructed in several ways. If you zoom in on the IKEA pics, you can see that this one is made up of several layers glued together. One of the reviews I came across actually recommended that type of construction, or several layers of those in various alignments.

 

Bamboo may not be neutral per se, but it may be more natural, especially regarding acoustic music.

[YashN]

find it too easy to reach out for support to one of the corners of the woofer box that doesn't have a device under it, and tipping it over. I may go to 4 devices per woofer too, just for a reasonable amount of stability.

 

Use a safety fall-back support device at these corners, which do not usually touch the lower surface of the component.

 

Do not use 4 unless you make absolutely sure that you have managed to make the 4 totally horizontally level.

 

If planarity is missing with 4, this will end up as chatter or additional sound coloration detrimental to the overall accuracy of music reproduction, hence the recommendation to use only 3, which is the minimum number to define a plane. Proper placement of the 3 will define the stability of the plane.

[YashN]

To the extent that any of these must bear a certain amount of weight over a given surface area size, isn't the "resonant frequency" ultimately determined by the weight of the device plus the platform? In other words, a lighter weight can use a less inflated tube, therefore a springier, lower resonance. A heavier weight object will put more pressure on the tube, thereby raising the effective air pressure and the resonant frequency. Obviously you can increase the size of the tube only so much...

 

Good question, once you add parts, there is a need to consider the new system's natural frequencies. This is why I am not too fond of the current air-cushion for now as I haven't seen any measurements relative to the frequencies and damping or the transfer chart, but that won't prevent me from trying it out and listen for SQ effects.

[YashN]

I meant to ask, where you find bamboo boards.

 

Forgot to mention that I found mine at the 'Dollar' Store nearby (it's actually called Dollarama here).

[AnotherSpin]

There are a few things to consider:

 

You'd rather use something like metal for the surface in contact with the ball.

 

The bamboo item can be constructed in several ways. If you zoom in on the IKEA pics, you can see that this one is made up of several layers glued together. One of the reviews I came across actually recommended that type of construction, or several layers of those in various alignments.

 

Bamboo may not be neutral per se, but it may be more natural, especially regarding acoustic music.

 

If you read my posts carefully, you might find out I use set in which balls contact metal. I also use very good Japanese bamboo boards, much better quality than those from cheap Ikea stock.

[Daudio]

Do not use 4 unless you make absolutely sure that you have managed to make the 4 totally horizontally level.

 

If planarity is missing with 4, this will end up as chatter or additional sound coloration detrimental to the overall accuracy of music reproduction, hence the recommendation to use only 3, which is the minimum number to define a plane. Proper placement of the 3 will define the stability of the plane.

 

A 6 foot tall, 95 lb speaker has to high a center of gravity to worry about a little 'possible' chatter. Besides I'm sure the carpet everything rests on will take up any small irregularities.

 

The subs are only 24" tall, so a different situation.

 

And, I am still interested in Johns's actual experiences.

[YashN]

A 6 foot tall, 95 lb speaker has to high a center of gravity to worry about a little 'possible' chatter.

 

You'd worry about it if you were serious about getting great sound.

[YashN]

I also use very good Japanese bamboo boards, much better quality than those from cheap Ikea stock.

 

What about their construction (in terms of layers)?

[AnotherSpin]

What about their construction (in terms of layers)?

 

Visually it has layers.

[YashN]

Visually it has layers.

 

I'll see if I can find that review or article about bamboo and audio. It goes to some length with that construction or layering aspect.

[YashN]

Here it is:

 

Audiobeat - The Best Things in Life Are (Almost) Free: IKEA's Aptitlig Chopping Boards

 

What makes bamboo so effective in the audio world is its structure and the process that allows us to turn what is basically a massive fibrous grass into a flat board. The bamboo itself is formed from long bundles of cellulose fibers, bound together by lignin, a natural thermoplastic resin. The closer to the surface you get, the greater the density of those fibers. The result is not unlike natural carbon fiber, but considerably heavier. Take that structure and cut it into strips that can then be stacked face to face to create a single flat board and you have a random, composite, variable-density material -- which is just about ideal for dissipating mechanical energy effectively without converting it into a single, dominant resonant frequency the way that glass or MDF does. Great in theory -- how does it work in practice? Better than you are going to believe -- which is exactly why Atacama and Quadraspire have made it central to their product lines.

[Daudio]

You'd worry about it if you were serious about getting great sound.

 

 

I am serious about a lot of things, and have to balance them to achieve the best all around results for my life.

 

One thing I am serious about is not getting told what to do by a 'Google Gadfly' with a lot of unconnected and conflicting data rattling around uselessly in his youthful head, precious little wisdom, diarrhea of the fingertips, and a decidedly rotten attitude !

 

Good Bye

[AnotherSpin]

Here it is:

 

Audiobeat - The Best Things in Life Are (Almost) Free: IKEA's Aptitlig Chopping Boards

 

Thank you, I read that article before I started my bamboo experiments. I tried various bamboo boards, of different design. Never tried Ikea, it has measurements which doesn't fit into my existing DIY support system. But, I tried more expensive square shaped thick bamboo boards of layers construction, both horizontal and vertical. Such as:

 

[sig8]

I have read that marble tiles to go under the equipment (above the roller balls) should be 1/2" thick. I am having no luck finding them; all I find is 18"x18", 3/8" thick tiles. How critical is this?

 

Also on the same lines; 3/4" birch plywood is common, 1" is special order; again is it critical or not a deal breaker.

 

Thanks.

[sig8]

Thank you, I read that article before I started my bamboo experiments. I tried various bamboo boards, of different design. Never tried Ikea, it has measurements which doesn't fit into my existing DIY support system. But, I tried more expensive square shaped thick bamboo boards of layers construction, both horizontal and vertical. Such as:

 

[ATTACH=CONFIG]19770[/ATTACH] [ATTACH=CONFIG]19771[/ATTACH]

 

Where you find these, and you are placing them I guess under the component above the marble tile I guess, is that correct? Thanks.

[AnotherSpin]

Where you find these, and you are placing them I guess under the component above the marble tile I guess, is that correct? Thanks.

I was buying those boards online. And it was before I started tubes/balls. Never tried bamboo combined with marble, and I believe marble/plywood should work ok. According to Barry you shouldn't prefer thick boards over thinner if latter have required hardness and rigidity. Surface which contacts balls should be very smooth.

[Otherworld74]

If the bottom of your speakers is smooth, do you need anything between the balls and the speaker?

[YashN]

One thing I am serious about is not getting told what to do by a 'Google Gadfly' with a lot of unconnected and conflicting data rattling around uselessly in his youthful head, precious little wisdom, diarrhea of the fingertips, and a decidedly rotten attitude !

 

You're classless and ignorant. Join the other trolls.

[Daudio]

Join the other trolls.

 

Sigh... Normally I like Canadians, too bad...

 

BTW, while you are Googling look up the definition of 'troll', fool.

[kumakuma]

BTW, while you are Googling look up the definition of 'troll', fool.

 

Good advice. He clearly doesn't understand what a troll is.

[groovybassist]

YashN:

 

The only poster that continues to prove they are a classless, ignorant troll is you. This I can tell you're serious about, as you sure are trying hard.

[AnotherSpin]

If the bottom of your speakers is smooth, do you need anything between the balls and the speaker?

 

If it smooth and very hard (balls will not dent and leave traces on its surface under weight) it may work, I guess.

[jabbr]

When using marble under components and on top of bearings -- what size tile?. Barry mentioned 20x20 plywood -- does this mean 18x18 x 3/8" marble tile or smaller tiles eg 12x24 that are 1/2" thick -- Home Depot doesn't have 18x18x1/2 -- what are people using?