Equipment isolation and vibration damping.

InfernoSTi · July 22, 2015

Hi John,

Are you using the rollers below the air bearing? If so, have you tried it the other way (shelf - air bearing - platform - rollers - component or tile-component)?

The main thing is you are happy with the results. I wonder if reversing the setup (rollers on top) might make you even happier?

Just a thought.

Best regards,

Barry

Soundkeeper Recordings

http://www.soundkeeperrecordings.wordpress.com

Barry Diament Audio

I've just tried them the one way, not the other way around. My assumption was there should not be a difference if each is doing its job? If there is a difference, what would cause that to be the case?

I will try things the other way around and see if I can hear a difference.

Thanks for the idea, Barry...

John

bdiament · July 22, 2015

I've just tried them the one way, not the other way around. My assumption was there should not be a difference if each is doing its job? If there is a difference, what would cause that to be the case?

I will try things the other way around and see if I can hear a difference.

Thanks for the idea, Barry...

John

Hi John,

I believe your assumption makes sense. However, I've also found that isolation seems to work best when it is placed as close as possible to that which we wish to isolate. In this case, having tried (and currently using) both, I find giving "priority" to the rollers (i.e., the horizontal and rotational planes) to be sonically advantageous.

Does this mean horizontal vibrations potentially do more damage than vertical ones? I don't know but I think this is a possibility. Another, perhaps stronger possibility is that there just happen to me more horizontal ones than vertical ones. (To my current understanding -- always subject to modification of course -- seismologists refer to the former as "primary" and the latter as "secondary".)

Best regards,

Barry

YashN · July 22, 2015

I have both the ESS rack and the Entreq Silver Minimus.

The ESS rack is nothing short of incredible. It was probably the biggest leap in my system in terms of musical enjoyment.

And I wouldn't listen to my digital source without the Entreq box.

Thanks for the feedback, skyline.

There's quite a hefty and thoroughly interesting thread where we talk about the Entreq and Tripoint devices as well as grounding among other things if you want to share your listening impressions there, that would be awesome too:

[h=2]AC Filtering, Grounding Boxes, Linear PSU and Balanced Power.[/h]

YashN · July 22, 2015

Does this mean horizontal vibrations potentially do more damage than vertical ones? I don't know but I think this is a possibility. Another, perhaps stronger possibility is that there just happen to me more horizontal ones than vertical ones. (To my current understanding -- always subject to modification of course -- seismologists refer to the former as "primary" and the latter as "secondary".)

In seismic event, if I remember correctly, the P Waves are larger than the S waves.

Additionally, S waves do not travel through liquid...

Now, as mentioned previously (first post), the air-cushion predominantly is dealing with vertical isolation (or at least the predominant goal of using it by those installing it is avowed to be this).

However, since the air-cushion in the form of a partially inflated inner tube has freedom of motion in all directions, it can also help isolate for vibration and rotation in the horizontal plane, as well as provide some isolation from tilt, i.e. rotation around axes in the horizontal planes.

So, I would say that if the inner tube is used below the cup-and-ball, it is already pre-filtering some of the horizontal plane vibrations and rotations before they reach the cup-and-ball.

Daudio · July 22, 2015

Gosh, I hope I didn't seem bossy Dave- my apologies.

Forrest,

Sorry, I did not mean anything by the "Ok with that" thing. It was poorly expressed, and not meant to have any negative connotations. My apologies.

If it were me, I think I would take the valve out of the Schrader valve body and glue in a 3mm tube long enough to extend to the rear. There I would have a needle valve and a low pressure air gauge (15 psi?). All of that should be available at Menards btw, or Mcmaster Carr of course. If one really wanted to trick it out, once the known pressure is determined, the tubes could be evacuated, and filled with SF6 which is 5-10x more compressible than atmosphere, whereby lowering the resonant freq.

I agree that would be a better way to go, but the original questioner seemed to want an easier solution, and that's why I was perusing that avenue.

I too would like a flexible fill tube to easily route out of the inner, inner tube ( ). I still have strong reservations about anything that distorts the shape of the rubber torus as it does its job of supporting the load and absorbing small vertical movements (vibration). Including turning them inside-out, which I think would change the stress's in the rubber walls. (probably not enough to negate the value of an easy fill access in tough situations, through).

Daudio · July 22, 2015

However, since the air-cushion in the form of a partially inflated inner tube has freedom of motion in all directions...

Not really. Draw a cross-section through the center of an inner tube used as an air bladder support for audio...

The bottom line represents the base plate, the top line represents a plate supporting some gear. Separating those two lines are two circles, partially flattened on the top. The circles represent two slices of the torus of the inner tube.

Now imagine a horizontal force applied to the right side of the base plate. The right side of the tube would want to roll clockwise to accommodate the applied force, and it looks like it could in our drawing. BUT, the rest of the torus can not roll clockwise, or any-wise, since it is all part of the same structure, but oriented up to 90 degrees off axis, and resisting that roll, and the applied force, spreading it out over the entire structure. Therefore coupling, not isolating.

Put another way: The inner tube is 'soft' in the vertical plane, but rigid in the horizontal plane.

Don't believe me ? Try pushing that top plate around in any horizontal direction. Doesn't want to move, does it ?

P.S I know that YashN probably has me on 'Ignore', so this is for everyone else

4est · July 22, 2015

No worries!

Well, the Schrader valve body is about 6mm, and the bladder tube needs to be inflated beyond that, let's say 8mm. 8mm-3mm tubing-2mm tube wall=3mm clearance. IDK, seems like it ought to be OK. If you were really worried about the discontinuity, you could throw a couple more equidistant around the bladder...

Forrest,

Sorry, I did not mean anything by the "Ok with that" thing. It was poorly expressed, and not meant to have any negative connotations. My apologies.

I agree that would be a better way to go, but the original questioner seemed to want an easier solution, and that's why I was perusing that avenue.

I too would like a flexible fill tube to easily route out of the inner, inner tube ( ). I still have strong reservations about anything that distorts the shape of the rubber torus as it does its job of supporting the load and absorbing small vertical movements (vibration). Including turning them inside-out, which I think would change the stress's in the rubber walls. (probably not enough to negate the value of an easy fill access in tough situations, through).

4est · July 22, 2015

You have company!

P.S I know that YashN probably has me on 'Ignore', so this is for everyone else

sig8 · July 22, 2015

I raised the question of valve stem location yesterday; towards the inside vs outside.

There are two options; twist the tube so that the valve is towards the outside (I tried that last night, see my post #577 above), or have some kind of valve extension and keep the valve stem in its original location (inside).

I know twisting the tube exerts additional stresses in the tube material, in addition to the stresses caused by blowing the tube itself. So overall it becomes a complex equation. But twisting the tube sure makes it lot easier to manage pressure in the tube.

I checked in the morning, and tube (valve stem) is holding its position (not trying to go back to its original state).

Hope it helps. Thanks.

sig8 · July 22, 2015

My spkr platform (Barry design). Works like a charm

[ATTACH=CONFIG]19536[/ATTACH]

I saw this little older post; what is on top of the roller balls, I see a tile or plywood? Thanks.

Foggie · July 23, 2015

I saw this little older post; what is on top of the roller balls, I see a tile or plywood? Thanks.

Here is a better pic. It's rollers > tile > plywood (which the spkrs rest on)

The little "blocks" are just there for a some reassurance They're not touching the tile and I actually removed them and filled the large voids (of the triangle) with large spare plywood cuts. In reality, one would have to give a pretty firm shove or bump to the spkrs before choice words would be said

4est · July 23, 2015

I noticed this too, and felt it was a prudent move.

[ATTACH=CONFIG]19883[/ATTACH]

Here is a better pic. It's rollers > tile > plywood (which the spkrs rest on)

[ATTACH=CONFIG]19882[/ATTACH]

The little "blocks" are just there for a some reassurance They're not touching the tile and I actually removed them and filled the large voids (of the triangle) with large spare plywood cuts. In reality, one would have to give a pretty firm shove or bump to the spkrs before choice words would be said

bdiament · July 23, 2015

I raised the question of valve stem location yesterday; towards the inside vs outside.

There are two options; twist the tube so that the valve is towards the outside (I tried that last night, see my post #577 above), or have some kind of valve extension and keep the valve stem in its original location (inside).

I know twisting the tube exerts additional stresses in the tube material, in addition to the stresses caused by blowing the tube itself. So overall it becomes a complex equation. But twisting the tube sure makes it lot easier to manage pressure in the tube.

I checked in the morning, and tube (valve stem) is holding its position (not trying to go back to its original state).

Hope it helps. Thanks.

Hi sig8,

The question becomes, is the tube as flexible and "loose" as it would be in its normal (valve facing inward) state?

I would tend to think it is more "tight" with the valve outside, making it stiffer.

Best regards,

Barry

bdiament · July 23, 2015

Not really. Draw a cross-section through the center of an inner tube used as an air bladder support for audio...

Hi Dave,

The "problem" here is that you are speaking from direct experience as opposed to not having any experience with this, theorizing a lot (often erroneously), and simply repeating what others have said as if you discovered it. Now who am I going to believe about how the water feels: Someone who has spent some good time swimming? Or someone who might have (or might not have) dipped their toe in once? ;-}

My experience matches yours: the air bearing works well vertically and doesn't do much horizontally. To be clear, it might be more than zero in the horizontal plane but it is essentially close enough to zero that this is how I think of it. And rotationally, does even less. That is why I feel the rollers are such a good idea. (And it is probably why air bearings aren't used under skyscrapers in earthquake-prone areas, while rollers are.)

Best regards,

Barry

InfernoSTi · July 23, 2015

Barry,

I have reversed the order under my DAC and my pre amp and am listening for a while.

I have a question about the order of the two elements, the tube and the rollers. Could it be that there is less overall weight and mass the closer to the equipment the rollers are and this is why it may sound better? I'm interested in your thoughts in this idea?

John

AnotherSpin · July 23, 2015

Hi sig8,

The question becomes, is the tube as flexible and "loose" as it would be in its normal (valve facing inward) state?

I would tend to think it is more "tight" with the valve outside, making it stiffer.

Best regards,

Barry

Soundkeeper Recordings

www.soundkeeperrecordings.wordpress.com

Barry Diament Audio

Barry, I could agree with your idea that keeping tube in its normal state may give it more flexibility and looseness. However, in my experience I could decrease tube to slightly inflated state only in "valve outside" mode under board weight, if I not go through attaching additional valve extender or making hole in the board.

bdiament · July 23, 2015

Barry,

I have reversed the order under my DAC and my pre amp and am listening for a while.

I have a question about the order of the two elements, the tube and the rollers. Could it be that there is less overall weight and mass the closer to the equipment the rollers are and this is why it may sound better? I'm interested in your thoughts in this idea?

John

Hi John,

I don't believe a well-designed roller will "care" about the weight of the load.

I have them under quite light DVD players and line stages, as well as under quite heavy amps, speakers, and subwoofers.

My feeling is the less there is between the rollers and what they isolate, the less there is to isolate. Not a matter of weight but a matter of what there is to "shake."

Best regards,

Barry

bdiament · July 23, 2015

Barry, I could agree with your idea that keeping tube in its normal state may give it more flexibility and looseness. However, in my experience I could decrease tube to slightly inflated state only in "valve outside" mode under board weight, if I not go through attaching additional valve extender or making hole in the board.

Hi AnotherSpin,

A hole in the board is a good idea. It eliminates the need for the straw too.

Best regards,

Barry