Stephen Scharf
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Seriously good isolation for your system; no expensive high-end racks, bits, bobs needed
Jan Vigne
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Thanks for posting, SS. I can't imagine a component that will not perform well on one or all of these set ups. If it has tubes, this is a must IMO.

Now you need to perform and report on your extensive ABX DBT's into the sound of red marbles vs. blue marbles.

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i'll have to give these tweaks a try, especially since i'm a college student on a limited budget. thanks for the cash saving ideas!

Stephen Scharf
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Quote:
Thanks for posting, SS. I can't imagine a component that will not perform well on one or all of these set ups. If it has tubes, this is a must IMO.

Now you need to perform and report on your extensive ABX DBT's into the sound of red marbles vs. blue marbles.

Thanks, Jan. I am surprised this post did not garner more response. I posted a similar thread on Steve Hoffman's forum, recapping Barry's work with my own experiences, and it generated over 50 replies.

Regarding DBTs for marbles; my stainless steel ball bearings came in today, so that's the setup for now.

I know this will be controversial view, but I am of the opinion that true improvements in an audio system will hold up to a double blind test. It's either truly better or it isn't. If the hyphothesis that something makes an audio system sound better is really true (in the sense of a null or alternative hypothesis test), it will hold up in a DBT test and one can run statistically meaningful proportion tests on a sample of listeners to evaluate the test. All the arguments by high-end magazine editors that DBTs are not applicable in audio reviewing is a crock, IMHO. It's my personal opinion that this view is just another manifestation of an inability to be truly objective.

mrlowry
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I've been interested since your very first post on the DIY roller blocks. I'm staying tuned for the update on the difference in sound between the glass marbles and the steel ball bearings. I have my theories but I won't introduce any biases into you experiment by stating them just yet.

JoeE SP9
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Thanks for the tips. I'm going to give them a try. I'll be doing the power amps first. They're on home made stands behind my speakers.

Stephen Scharf
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The steel ball bearings make an audible improvement, but it is not "significant". That is, not as significant as going from no isolation, e.g. not having the component on an inner tube, to isolation, that is, having the component on an inner tube. Or, going from no roller bearings to roller bearings, but it is an improvement. One thing is that they have are more uniform in size than marbles, more truly spherical, and have markedly less friction. But you are only going to get so much improvement out of them using them in a plastic furniture cup. Using them with true, machined and polished roller blocks would likely result in a bigger improvement than I have noticed, I would guess. But those would cost about 10X as much, so there ya go.

Stephen Scharf
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So, let us know what you find out.

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Stephen,

I can see the need for isolating the source of sound, such as a turntable. I am not convinced that electronics need this kind of treatment, even though an audiophile friend of mine swears by it.

I think through what is the 'problem' you are trying to solve. The inner tube is intended to reduce/eliminate possible vibration of the turntable caused by the shelf or support it sits on, presumedly from the shaking from the bass transmitted throught the floor to the shelf. Is this problem significant enough for electronics? I don't know.

One might suspend all equipment from the ceiling on springs with a very low combined resonant frequency of say 5 Hz, and get equivalent or better(?) results. But this is definitely not an aesthetically-pleasing route!

Since the above approaches do not isolate the equipment against air-borne vibrations, which one is more important, structural or air?

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Quote:
Stephen,

I can see the need for isolating the source of sound, such as a turntable. I am not convinced that electronics need this kind of treatment, even though an audiophile friend of mine swears by it.

I think through what is the 'problem' you are trying to solve. The inner tube is intended to reduce/eliminate possible vibration of the turntable caused by the shelf or support it sits on, presumedly from the shaking from the bass transmitted throught the floor to the shelf. Is this problem significant enough for electronics? I don't know.

One might suspend all equipment from the ceiling on springs with a very low combined resonant frequency of say 5 Hz, and get equivalent or better(?) results. But this is definitely not an aesthetically-pleasing route!

Since the above approaches do not isolate the equipment against air-borne vibrations, which one is more important, structural or air?

WTL,
I was dubious of this too, until I tried it. My local dealer suggested putting an inner tube under my Arcam AVR280. I thought it was a bunch of hoo-ha until I tried it. But I tried it, and he was right. It did sound better. Everything I put an inner tube under sounds better. Then I started playing with the roller blocks on top of a board that was resting on the inner tube. More improvement. These tweaks were suggested by Barry Diament on Steve Hoffman's forums. The Townsend Seismic Sinks work in the same way; they are just WAY more expensive than a $6 inner tube.

You may or may not think these things can help an electrical component, but my experience, discovered from trying it while initially quite skeptical, is that it really does...it makes your system, as Barry puts it, sound "bound and gagged no more..."

BTW, your friend is right....

But don't take my word for it...try it for yourself.

See what you think. You've got nothing to lose, 'cept maybe six bucks. Or go whole hog, and put your preamp on a board on the inner tube resting on the roller block system I describe here. It will set you back a whopping twenty bucks or so.

absolutepitch
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Quote:
... These tweaks were suggested by Barry Diament on Steve Hoffman's forums. The Townsend Seismic Sinks work in the same way; they are just WAY more expensive than a $6 inner tube. ...

The description of "Seismic Sinks" implies the vibrations are structural. In this case, the isolation provided by the inner tube may be what is needed. I'm just adding a bit of technical inquiry into the reported improvement.

It may or may not be good for turntables, which already have its own isolation designed into it. Adding another spring (inner tube) can induce more vibration at certain frequencies and reduce vibration at others. One does not know what frequencies are transmitted more and what frequencies are isolated more. Does sounding better (subjective impression) correlate with reduced transmitting of vibration (objective data)? I won't know without doing the experiment.

Putting inner tubes below speakers probably is not a good idea, whereas it may be helpful for electronics, from a vibration point of view.

Stephen Scharf
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Quote:

Quote:
... These tweaks were suggested by Barry Diament on Steve Hoffman's forums. The Townsend Seismic Sinks work in the same way; they are just WAY more expensive than a $6 inner tube. ...

The description of "Seismic Sinks" implies the vibrations are structural. In this case, the isolation provided by the inner tube may be what is needed. I'm just adding a bit of technical inquiry into the reported improvement.

It may or may not be good for turntables, which already have its own isolation designed into it. Adding another spring (inner tube) can induce more vibration at certain frequencies and reduce vibration at others. One does not know what frequencies are transmitted more and what frequencies are isolated more. Does sounding better (subjective impression) correlate with reduced transmitting of vibration (objective data)? I won't know without doing the experiment.

Putting inner tubes below speakers probably is not a good idea, whereas it may be helpful for electronics, from a vibration point of view.

Seismic Sinks is just a product name.

I wouldn't put inner tubes beneath speakers, either. But they really help electronics and TTs.

All this analysis is well and good (I'm a scientist by profession, so I know where you're coming from), but my recommendation is:

go out and try it!

You've got nothing to lose except the grunge in your system.

absolutepitch
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Quote:
Seismic Sinks is just a product name.

I wouldn't put inner tubes beneath speakers, either. But they really help electronics and TTs.

All this analysis is well and good (I'm a scientist by profession, so I know where you're coming from), but my recommendation is:

go out and try it!

You've got nothing to lose except the grunge in your system.

I'm sure the name used is a trade name. The Seismic part is probably more than just a name, and describes what it may be doing.

I've tried supports below speakers combining foam for damping and spikes for coupling to the wood floor below the carpet. The spikes made the most difference in the bass, subjectively more preferable.

If the inner tube bases work for the electronics, and presuming that the electronics need vibration isolation from the shelf, then maybe it will also work by discreetly damping the innerds of the electronics without the inner tube. Maybe better targeted application of damping?

I would be concerned with the turntable. I guess it depends on what the suspension the TT has relative to the inner tube. Someday, given the time, I would like to see how much vibration is really transmitted through to the TT with and without the innertube support. Have you tried to measure this?

Stephen Scharf
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Quote:

Quote:
Seismic Sinks is just a product name.

I wouldn't put inner tubes beneath speakers, either. But they really help electronics and TTs.

All this analysis is well and good (I'm a scientist by profession, so I know where you're coming from), but my recommendation is:

go out and try it!

You've got nothing to lose except the grunge in your system.

I'm sure the name used is a trade name. The Seismic part is probably more than just a name, and describes what it may be doing.

I've tried supports below speakers combining foam for damping and spikes for coupling to the wood floor below the carpet. The spikes made the most difference in the bass, subjectively more preferable.

If the inner tube bases work for the electronics, and presuming that the electronics need vibration isolation from the shelf, then maybe it will also work by discreetly damping the innerds of the electronics without the inner tube. Maybe better targeted application of damping?

I would be concerned with the turntable. I guess it depends on what the suspension the TT has relative to the inner tube. Someday, given the time, I would like to see how much vibration is really transmitted through to the TT with and without the innertube support. Have you tried to measure this?

No, but I would if I had access to the appropriate metrology. I don't have accelerometers or Keyence laser-based metrology system for measuring ringing components. But if I did, I would be doing DOE's to determine the main effects, e.g. the effect of air pressure, and if there were any interactions, which I am sure there are. One could use Response Surface DOE to optimize the setup with respect to minimizing ringing.

JoeE SP9
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I tried the roller blocks and inner tubes under my mono, tube power amps. I already had them sitting on granite slabs with hockey pucks under them. The inner tubes and roller blocks are staying!
Oh, I hear less and more, blacker blacks less microphonic type noise, there is an overall improvement. IMHO (I've gotta say that because all the DBT'rs are really rabid lately) my power amps sound better on the roller block bike tube isolation. Try it yourself you'll like the results. If you feel there is no difference so what. You only spent a couple of bucks.
I'm going to tell my audio buddies about this. I'll let you folks know what they think.

Stephen Scharf
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Joe,
Yeah, I knew it would work....I've pulled my stuff off the roller blocks and inner tubes a bunch of times just to compare once again, and every time, the stuff goes back on the roller blocks and inner tubes. It really does work in making your system sound better, there's no doubt about it in my mind.

Very glad to hear it worked out for you.

JoeE SP9
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I won't even bother going back. I like what I hear now. My preamp will be next. That will take care of my tube gear. My TT will be after the preamp.

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Hi Stephen,


Quote:
I've posted here before about the marked improvements you can make by putting your gear on a partially inflated inner tube, and Jan Vigne has posted some great advice about using squash balls and QuikCaps as well. Barry Diament of Soundkeeper Recordings and Barry Diament Audio has been recommending something similar for quite a while now on Steve Hoffman forums. Barry has been a proponent of inner tubes for quite a while as well as recommending using them in combination with "roller blocks" (in fact, I posted my roller block TT setup here a while ago, based on Barry's guidelines). Well, while I've had my TT's in this type of set up for a quite while, and now, it was time to get the preamp and amp set up this way as well...

If anyone is interested in an article I wrote on the subject ("Vibration control for better performance"), it can be found here.

Best regards,
Barry
www.soundkeeperrecordings.com
www.barrydiamentaudio.com

Stephen Scharf
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Barry,
Thanks for coming on over to Stereophile and posting a link to your article.

Here's another tidbit that I am sure will not surprise you.

I had to remove by power amp from it's setup because the inner tube had gone flat from air leaking out over time. After re-inflating it and placing it back under the board, I put the Premier 11A back on the board w/o the "roller blocks" and listened for a bit (approx 30 min). It sounded good, but not as good as I was used to. I then reinstalled my homemade version of your Hip Joints (TM) aka homemade roller blocks, the sound once again opened up and got better in pretty much every respect we've been discussing on Steve's forum. Basically, improvements across the board (no pun intended!)

bdiament
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Hi Stephen,


Quote:
Barry,
Thanks for coming on over to Stereophile and posting a link to your article.

Here's another tidbit that I am sure will not surprise you.

I had to remove by power amp from it's setup because the inner tube had gone flat from air leaking out over time. After re-inflating it and placing it back under the board, I put the Premier 11A back on the board w/o the "roller blocks" and listened for a bit (approx 30 min). It sounded good, but not as good as I was used to. I then reinstalled my homemade version of your Hip Joints (TM) aka homemade roller blocks, the sound once again opened up and got better in pretty much every respect we've been discussing on Steve's forum. Basically, improvements across the board (no pun intended!)

In my experience, air bearings do require periodic adjustment in the amount of air. My Enjoyyourshelf

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Quote:
Hi Stephen,
<SNIP>

The combination of air bearings (for vertical isolation) and roller bearings (for horizontal and rotational isolation) really do make for some wonderful performance improvements, don't they? At this point, I can't imagine my gear not "floating".

Best regards,
Barry

Boy, I'll say. I can't imagine not having my gear "floating", either. Far as I am concerned, if you're not listening to gear set up this way, you are not hearing how the gear really sounds.

Jan Vigne
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Stephen, one of the reasons I chose the raquetballs with QuikCaps is to avoid the issues of a slowly leaking inner tube.

Whichever way you go, attention paid to isolation and vibration control will bring out the best in all equipment.

geoffkait
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Yup, inner tubes and bladders leak like a seive. And while they're leaking isolation performance is compromised 'cause the thing is constanltly shifting. Even worse is their crappy surface area to volume ratio. Gimme good old steel springs any day. They don't leak, don't have much internal friction and are very linear.

Jan Vigne
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But have a very noticeable resonance I would suppose.

geoffkait
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Not really. Maybe just a bit, hardly enough to notice. The springs are in compression, which disallows most ringing in the metal. Any residual resonances one might object to can be tamed viscoelastically.

Jan Vigne
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"Disallows"! Sounds like a nun I had in grade school.

geoffkait
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Stops, suppresses, constrains, damps, prohibits, quiets, tames, cancels, checks, curbs, quells, silences. Any of those words more Presbyterian to you?

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Quote:
Stephen, one of the reasons I chose the raquetballs with QuikCaps is to avoid the issues of a slowly leaking inner tube.

Whichever way you go, attention paid to isolation and vibration control will bring out the best in all equipment.

Agreed.
The only component that gives me problems with the inner tube deflating is the 55 lb Conrad-Johnson Premier 11A. But I know a way to fix that: SLIME!
Slime is great because it coats the inside of the inner tube to prevent flats...it also prevents air leaking out of inner tube or valve stem.

One of the reasons I am presently using an inner tube for my amp and preamp is that it is thinner, and fits in the shelves in my audio rack and still allows me to put my "roller block" system underneath, and leave room at the top keeping things cool, making connections, etc. I am using 12" pillars in my Sanus rack to be able to do this; the 8" ones were not tall enough, even with just using an inner tube. That bank of transformers in the Pr 11A sticks up pretty high in back.

Both systems work well for providing isolation.

Cheers,
Stephen.

Jan Vigne
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Slime = Leak Stop?

rvance
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Yea, Slime works. I used it on a wheelbarrow tire w/success but it (tire/tube) needs to be spun so centrifugal force distributes it to all surfaces of the tube. Comes with a valve remover tool to better squeeze in the goop.

BTW, the best hedge against valve leaks is the little plastic valve cap. They can hold 100 lbs. pressure without the schrader mechanism in place.

Buddha
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Keep in mind, there is tube to tube variation.

Here is a 'pre-slimed' tube that would save someone the bother.

Rvance is right, Presta valves are better at holding air than Schrader valves.

Here's another tube along those lines.

You can also experiment and compare butyl, latex, and MTB tubes; and you can even interdigitate more than one tube for heavier gear.

If you want to get really esoteric, you can get different size tubes, filled to different pressures, and adjusted so both are supporting weight, but they will have different 'reasonance' characteristics.

I think the wave of the future may be supports with differing characteristics under the same piece of gear. The two-tube thing may offer even more than one.

Maybe different brands of racquet/squash/hand/tennis balls, too.

Some might say that the various types of balls are supposed to have identical specifications, but we all know that specs don't always tell the full story.

Maybe three different brands of a certain type of ball used one each beneath a piece of gear?

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Hi Jan,


Quote:
Stephen, one of the reasons I chose the raquetballs with QuikCaps is to avoid the issues of a slowly leaking inner tube.

Whichever way you go, attention paid to isolation and vibration control will bring out the best in all equipment.

There are certainly many approaches one can take.
I like the lower resonance frequency of inner tubes vs. racquet balls.

As to the periodic need for inflation adjustment, this takes me a few seconds per tube once a month or so. (My setup allows me to change inflation without having to remove the gear first. I can change inflation while the music is playing.)

Best regards,
Barry
www.soundkeeperrecordings.com
www.barrydiamentaudio.com

geoffkait
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Agree w/ the statement the lower the resonant frequency the better. This happens to be a limitation of the inner tube even when it doesn't leak. The resonant frequency of an air bladder turns out to be a function of the ratio of the surface are over the volume. For inner tubes and bladders and balls this ratio is fairly low due to the high surface area of the compressed bladder/tube and the low volume of the balls.

My Nimbus Platform, to use a prime example, uses a *single* airspring with auxillary air cannister connected to the airspring via NPT air fitting. The airpspring is a convoluted type with a quite small surface area and machined to accept the air fitting. This novel design not only yields a very low resonant frequency by virtue of a single airspring (instead of 3 or 4), but produces a Very Low surface area/volume (when the volume of the large air cannister is considered). Result - resonant frequency of Nimbus is below 1 Hz. The typical resonant frequency of an inner tube, bladder or squash ball type device is around 3 Hz at best. Nimbus employs a Firestone airspring with thick walls, so it won't leak significantly even over the course of a year. I should point out another big advantage of Nimbus' unipivot design - it isolates in all 6 directions.

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Hi Geoff,


Quote:
Agree w/ the statement the lower the resonant frequency the better. This happens to be a limitation of the inner tube even when it doesn't leak. The resonant frequency of an air bladder turns out to be a function of the ratio of the surface are over the volume. For inner tubes and bladders and balls this ratio is fairly low due to the high surface area of the compressed bladder/tube and the low volume of the balls.

What I take from this (and my experience supports this) is that not all air bearings are equal. This is true of roller bearings as well, of course.


Quote:
My Nimbus Platform, to use a prime example, uses a *single* airspring with auxillary air cannister connected to the airspring via NPT air fitting. The airpspring is a convoluted type with a quite small surface area and machined to accept the air fitting. This novel design not only yields a very low resonant frequency by virtue of a single airspring (instead of 3 or 4), but produces a Very Low surface area/volume (when the volume of the large air cannister is considered). Result - resonant frequency of Nimbus is below 1 Hz. The typical resonant frequency of an inner tube, bladder or squash ball type device is around 3 Hz at best. Nimbus employs a Firestone airspring with thick walls, so it won't leak significantly even over the course of a year. I should point out another big advantage of Nimbus' unipivot design - it isolates in all 6 directions.

I get multiple axis isolation using a combination of air and roller bearings.
No doubt, the Nimbus system sounds wonderful and I'd love to hear one (or more) in my system some time.

The one area where it cannot compete, I'm afraid, is overall cost. Unless I'm mistaken, it will cost considerably more than a good air bearing and a set of roller bearings. This is true of the Townshend devices as well, which in my own auditions, I've found to also be excellent performers.

Obviously, if the cost differential is not a factor, I can certainly see a sonic edge for a device with an even lower resonance frequency, provided the rolloff above resonance is at least as steep, which I would assume, would be the case.

Best regards,
Barry
www.soundkeeperrecordings.com
www.barrydiamentaudio.com

Jan Vigne
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Quote:
There are certainly many approaches one can take.
I like the lower resonance frequency of inner tubes vs. racquet balls.

I would think the desired resonant frequency varies with the componet being supported. Wouldn't the racquetballs have a high "Q" to their resonance and therefore have a different and possibly desirable effect on the component?

In the case of the racquetballs on QuikCaps combination I tried to take advantage of a stiff, high "Q", higher frequency resonance sitting on top of a lossy, low "Q", lower frequency resonance system. The low frequency component (QuikCap) cannot pass much information to the high frequency component and what does pass between the two will result in a high "Q" which passes quickly at the junction with the component. For draining resonance from a heavy weight component, say, a tube power amplifier, I cut the ball in half and place the broad (cut) side against the component. The ball/cap system then rests on a layered platform of damped MDF sheets. For a lighter component, such as my tube pre amp, the ball is cut side down and then placed on a shelf (actually the three layered, internally damped MDF plinth to one of the original Well Tempered turntables) supported by QuikCap/ball systems on a semi-floating support shelf. As I look at the combination vibration can move down but not up and can be drained but not passed.

I would not think an inner tube to be the best solution for a turntable that lacks much in the way of its own suspension. Too much horizontal movement that would allow mistracking of the arm and therefore stylus by way of low frequency horizontal movement. The friction of the rollerballs in the horizontal - another aspect of the QuikCap with its slight center depression - should prevent much of this movement but an inner tube by itself, I wouldn't think to be ideal for a table.

What about an inner tube embedded within a box of sand?

bdiament
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Hi Jan,


Quote:
I would think the desired resonant frequency varies with the componet being supported. Wouldn't the racquetballs have a high "Q" to their resonance and therefore have a different and possibly desirable effect on the component?

In the case of the racquetballs on QuikCaps combination I tried to take advantage of a stiff, high "Q", higher frequency resonance sitting on top of a lossy, low "Q", lower frequency resonance system. The low frequency component (QuikCap) cannot pass much information to the high frequency component and what does pass between the two will result in a high "Q" which passes quickly at the junction with the component. For draining resonance from a heavy weight component, say, a tube power amplifier, I cut the ball in half and place the broad (cut) side against the component. The ball/cap system then rests on a layered platform of damped MDF sheets. For a lighter component, such as my tube pre amp, the ball is cut side down and then placed on a shelf (actually the three layered, internally damped MDF plinth to one of the original Well Tempered turntables) supported by QuikCap/ball systems on a semi-floating support shelf. As I look at the combination vibration can move down but not up and can be drained but not passed.

In my experience, what is desired in an isolation device, for all components, is as low a resonance frequency as possible, since isolation will begin above that frequency.

If the resonance is not kept way down, the result is a bump in the bass (in amplitude as well as a slow down in bass speed). This may not be an issue with a system that does not reach down into the bass. It also may be something some folks find pleasing. Personally, I want the resonance as low as I can possibly get it as this results in the isolation taking effect that much sooner.

I've also found a single "spring" per axis of motion works better than multiple springs "stacked" on each other, where each interferes with the energy transfer by the others.

As to draining, I personally don't subscribe to this. My feeling is that when something is drained, less of it should remain in the place from where it has been drained. For example, when I drain my kitchen sink, I end up with less water in the sink. If there is still water in the sink, I am not convinced any draining is occurring.

Now perhaps you mean you want to provide a path for vibrations to leave the component being isolated. My own intent is to block vibrations from the ground from entering the component. I see no advantage (and some disadvantage to providing a transfer path, which will always be a two-way street (regardless of what the marketers and those writers who unquestioningly echo them say).

In my view, attempts to alter the chassis' inherent resonance will certainly change the sound but unlike well designed and implemented isolation mechanisms, the results - to my ears - are not consistent and repeatable and are more in the line of random alterations (some of which may be pleasing).


Quote:
I would not think an inner tube to be the best solution for a turntable that lacks much in the way of its own suspension. Too much horizontal movement that would allow mistracking of the arm and therefore stylus by way of low frequency horizontal movement. The friction of the rollerballs in the horizontal - another aspect of the QuikCap with its slight center depression - should prevent much of this movement but an inner tube by itself, I wouldn't think to be ideal for a table.

I know a number of folks who have used a large diameter inner tube, minimally inflated, under turntables that lack their own suspensions. The results have been consistent, repeatable performance improvements. While there is some horizontal play, I find air bearings provide the overwhelming majority of their isolation in the vertical plane. (This is why I combine them with roller bearings, which when properly designed and implemented, will isolate in the horizontal and rotational planes.)


Quote:
What about an inner tube embedded within a box of sand?

If the sand is only underneath the tube and not at all impeding vertical compression of the tube, I don't think it will hurt. In my experience, sand settles and sometimes leaks (but the latter can be avoided with a well sealed enclosure). I don't really see any advantage to adding sand and do see the possibility of it impeding vertical compression of the tube.

Just my perspective.

Best regards,
Barry
www.soundkeeperrecordings.com
www.barrydiamentaudio.com

geoffkait
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"I get multiple axis isolation using a combination of air and roller bearings. No doubt, the Nimbus system sounds wonderful and I'd love to hear one (or more) in my system some time."

"The one area where it cannot compete, I'm afraid, is overall cost. Unless I'm mistaken, it will cost considerably more than a good air bearing and a set of roller bearings. This is true of the Townshend devices as well, which in my own auditions, I've found to also be excellent performers. Obviously, if the cost differential is not a factor, I can certainly see a sonic edge for a device with an even lower resonance frequency, provided the rolloff above resonance is at least as steep, which I would assume, would be the case."

Cost is a factor, of course, and Nimbus ain't cheap, that's true. But how does one weigh cost vs performance? Ah, the age old question. It would be an interesting challenge to try and establish the pecking order of, say, the top ten or fifteen isolation devices -- i.e., finding the system(s) out there that would do justice to the differences among them. I guess I was expecting some bold reviewer would come along and do just that. Maybe, realistically one can hope for a shoot-out between two iso devices. Let's say the Nimbus vs the Vibraplane. Or perhaps the steel spring'd Promethean with roller bearings vs. the Halcyonics. Heh heh

Machina Dynamica

bdiament
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Hi Geoff,

Any time you want someone to test a Nimbus product, please don't hesitate to contact me.

As to performance vs. cost, I understand your point. My problem is I'm not as wealthy as I might be. Hence, my offering my services as a volunteer tester.

Best regards,
Barry
www.soundkeeperrecordings.com
www.barrydiamentaudio.com

geoffkait
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I am attached at the hip to Nimbus as it was my first product. But I really like mechanical springs, too. Especially when used with nice thick, heavy bluestone slabs. Why, shucks, I can even slap together a stack of several heavy mass/spring layers (some skill is involved in deciding the resonant frequency of each layer) with a resonant frequency of about 1/3 Hz. Touch the stack with a finger and watch it sway and bobble up and down, slowly slowly. Like a big bowl of jello. Pretty cool. No messy air fittings, no leaky air bladders. And it's not really that expensive.

arnyk
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Quote:

I can see the need for isolating the source of sound, such as a turntable. I am not convinced that electronics need this kind of treatment, even though an audiophile friend of mine swears by it.

I looked at the OP, and noticed that some of the audio components receiving this treatment had bottles in them. There is a belief that bottles are microphonic, but in fact its just the broken ones that cause audible problems this way.

At some level just about every audio component is a tiny bit microprophonic, if you measure small enough differences. For example, some interconnects are more microphonic than a good tubed component.


Quote:

I think through what is the 'problem' you are trying to solve. The inner tube is intended to reduce/eliminate possible vibration of the turntable caused by the shelf or support it sits on, presumedly from the shaking from the bass transmitted throught the floor to the shelf. Is this problem significant enough for electronics? I don't know.

Depends on the electronics. To be completely non-microphonic electronics would need to be like a solid block of sorbothane - a solid block of steel is actually very microphonic.

In the days of tubes we did build a lot of very sensitive electronics that were for all practical purposes non-microphonic. Of ocurse I threw in that hook - practical purposes. High end audio seems to be more about phobias than real-world problems.

Using a massy platform resting on an inner tube is an old work-around, dating back to the early days of lasers and holograms. We're talking at least 30 years ago.

It can work if you need it. My house is built on a concrete slab that rests on a nice solid layer of damp sand. The framework is steel covered by wet plaster. Never felt the need, even in the days of vinyl.

One might suspend all equipment from the ceiling on springs with a very low combined resonant frequency of say 5 Hz, and get equivalent or better(?) results. But this is definitely not an aesthetically-pleasing route!

Since the above approaches do not isolate the equipment against air-borne vibrations, which one is more important, structural or air?

Jan Vigne
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Hot air or just air?

absolutepitch
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Quote:
One might suspend all equipment from the ceiling on springs with a very low combined resonant frequency of say 5 Hz, and get equivalent or better(?) results. But this is definitely not an aesthetically-pleasing route!

Since the above approaches do not isolate the equipment against air-borne vibrations, which one is more important, structural or air?

This was copied from my post from which you referred to. Were you going to comment further? I don't see anything after this part.

I guess it may be said that if the structural vibrations are reduced enough, airborne vibrations would remain as a problem.

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