Equipment isolation and vibration damping.

YashN · July 20, 2015

Click on the various photo highlight circles to see what's on offer from HRS and how they work.

Daudio · July 20, 2015

Hi Dave, Why assume the floor vibrations you felt were vertical?

Barry, I replied to you in post #546, but that may have become covered up by the normal accumulation of forum detritus over the weekend

Tintinabulum · July 20, 2015

Slightly off topic but on the subject of isolation, vibration etc, how much harm are humming transformers going to do to ones sound? Presumably there's a lot of vibration caused, is this going to be significantly impacting SQ (apart from about as long as a piece of string)? This is leading to- how much effort to I put into resolving this (balanced transformer, move home..)? Ta.

Sorry if this is detritus, just trying to get perspective...

Daudio · July 20, 2015

Sorry if this is detritus, just trying to get perspective...

One man's detritus, is another man's interesting conversation. Just a matter of perspective

bdiament · July 20, 2015

Barry, I replied to you in post #546, but that may have become covered up by the normal accumulation of forum detritus over the weekend

Hi Dave,

I saw the post, then got distracted by some non-audio necessities (aka Life and the health of a loved one who was in the hospital for a heart operation).

Also, I didn't really have much to say.

I don't know that I would draw the same conclusions, i.e., that the vibrations were vertical in nature.

Even if the subs are in direct contact with the floor (I'd consider "floating" them too. ;-}) and even if the floor is suspended on joists, I could be mistaken (of course) but I don't see why these would suggest the vibrations in the floor itself travel across the floor vertically rather than horizontally. Vibrations may *enter* the floor vertically but I'm not so sure this means they stay that way once the floor is energized.

As I said, I don't know. I would just tend to think the *primary* vibrations are horizontal if they are felt in a part of the room well away from where the subs contact the floor. Not to say the floor isn't *also* moving vertically. I'm thinking of seismic vibrations in the earth: the P (primary) waves move horizontally, the S (secondary) waves move vertically. Those P waves are what appear to do most of the damage.

Best regards,

Barry

completeluxury · July 21, 2015

Despite most of that HRS stuff being well out of my price range i wonder how these would go.

Nimbus System

they are well priced and they say it works on any shelf system so it might be a replacement for the cup and ball?

sig8 · July 21, 2015

Those of you who have tried bicycle tube method, including Barry, I have a question:

I think the idea is to keep the tube valve stem towards the outside for access. As we all know it is designed to be towards the inside of the ring, but I think once we force it and put some load on it, it will probably stay outside for access.

Is that how it is or am I missing something and we would need flexible valve extension, etc. for sure.

Please let me know. Thanks.

Daudio · July 21, 2015

Nimbus System

they are well priced and they say it works on any shelf system so it might be a replacement for the cup and ball?

Looks like squishy stuff in a metal cup to me

I wouldn't replace roller devices with them, But, I think it's great for people to experiment, listen, and judge for themselves. And then let us all know their results.

Daudio · July 21, 2015

I think the idea is to keep the tube valve stem towards the outside for access. As we all know it is designed to be towards the inside of the ring, but I think once we force it and put some load on it, it will probably stay outside for access.

Is that how it is or am I missing something and we would need flexible valve extension, etc. for sure.

Well, if you can turn an inner tube inside out, my hat's off to you

But there is the little matter that the inside diameter of the torus is considerably smaller then the outside diameter. So there is less rubber skin on the inside, and more on the outside. The structure will mightly resist efforts to deform it, probably only resulting in damage. But please try it if you think you can. They are certainly cheap enough to experiment with !

Daudio · July 21, 2015

I don't know that I would draw the same conclusions, i.e., that the vibrations were vertical in nature.
Even if the subs are in direct contact with the floor (I'd consider "floating" them too. ;-}) and even if the floor is suspended on joists, I could be mistaken (of course) but I don't see why these would suggest the vibrations in the floor itself travel across the floor vertically rather than horizontally. Vibrations may *enter* the floor vertically but I'm not so sure this means they stay that way once the floor is energized.

As I said, I don't know. I would just tend to think the *primary* vibrations are horizontal if they are felt in a part of the room well away from where the subs contact the floor. Not to say the floor isn't *also* moving vertically. I'm thinking of seismic vibrations in the earth: the P (primary) waves move horizontally, the S (secondary) waves move vertically. Those P waves are what appear to do most of the damage.

Barry,

Think of my floor as a trampoline, anchored at the edges, flexible in the center. That kind of structure supports vertical waves. And the center of my floor was where I first noticed the phenomenon.

But, who says it is only one kind of effect ? It is probably a combination of P and S waves. But I still think that S waves are predominant in my situation.

How would one measure this kind of thing ? I've been wondering about those accelerometers built in to the various iDevices lately.

Could they be used to accurately and reliability measure these small vibration vectors ?

sig8 · July 21, 2015

Well, if you can turn an inner tube inside out, my hat's off to you

But there is the little matter that the inside diameter of the torus is considerably smaller then the outside diameter. So there is less rubber skin on the inside, and more on the outside. The structure will mightly resist efforts to deform it, probably only resulting in damage. But please try it if you think you can. They are certainly cheap enough to experiment with !

Ok, bad idea, wouldn't work. As you know I am trying to gather whatever I need for a weekend trial, that is why the questions, and I do not have everything to try yet. Thanks for your help, but still questions;

I physically tried to turn the tube, but as you said stem tries to go back inside, but I thought it might stay there with load. So the question then is how do you adjust the inflation.

I do not want to pick my 75 lbs amp six times to adjust the pressure, and I really wouldn't know how much pressure to put without trying, so what is the answer?

Would flexible valve stems work, but would have to pass under the tube like the straw, or we may not need the straw, because flexible hose will create some gap.

Also there was a talk about valve extensions, etc. how they apply then?

Let me know please. Thank you for your help.

YashN · July 21, 2015

Slightly off topic but on the subject of isolation, vibration etc, how much harm are humming transformers going to do to ones sound? Presumably there's a lot of vibration caused, is this going to be significantly impacting SQ (apart from about as long as a piece of string)? This is leading to- how much effort to I put into resolving this (balanced transformer, move home..)

Good point, I am re-thinking my SET Tube Amp because of that.

bdiament · July 21, 2015

Those of you who have tried bicycle tube method, including Barry, I have a question:

I think the idea is to keep the tube valve stem towards the outside for access. As we all know it is designed to be towards the inside of the ring, but I think once we force it and put some load on it, it will probably stay outside for access.

Is that how it is or am I missing something and we would need flexible valve extension, etc. for sure.

Please let me know. Thanks.

Hi sig8,

I'd leave the valve on the inside. As Dave rightly points out, there is less rubber on the inside of the circle than there is on the outside.

A flexible valve extension helps with access. And yes, it *may* also provide enough of a gap to remove the need for the straw. However, it may also make for a bit of tilt. You would need to experiment to see.

Best regards,

Barry

Gilles · July 21, 2015

sig8,

You could use the tank valve G21TVB and the chuck valve pictured on page 7 of http://greenlinehose.com/_pdf/fittings/16.Accessories.pdf and connect them with a flexible hose of your choice, long enough to extend beyond the exterior circumference of the air chamber.

I bought a few of these for when I will take the time to try that.

Have fun!

Gilles

bdiament · July 21, 2015

Barry,

Think of my floor as a trampoline, anchored at the edges, flexible in the center. That kind of structure supports vertical waves. And the center of my floor was where I first noticed the phenomenon.

But, who says it is only one kind of effect ? It is probably a combination of P and S waves. But I still think that S waves are predominant in my situation.

How would one measure this kind of thing ? I've been wondering about those accelerometers built in to the various iDevices lately.

Could they be used to accurately and reliability measure these small vibration vectors ?

Hi Dave,

Understood about the floor. However, I still don't see this means vibrations in the floor are necessarily traveling vertically as opposed to horizontally.

Not sure how this could best be measured. Probably have to look into how seismologists do it. (There's a job. I can imagine a kid somewhere saying: "When I grow up, I want to be a seismologist." ;-})

Best regards,

Barry