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View Full Version : Any one know anything about the little isolator blocks you put under the feet of cdp?



Deaf Cat
2006-02-07, 07:05
Hiya,

As above really, have heard bits and bobs about these things and how they are supposed to make things sound better, just wondered if any one else had? or even tried a few...?

Just wondered the theory behind them and if such things may work on a SB?

Cheers!

Heimiko
2006-02-07, 07:49
Those "feat" for under cdp's are to prevent vibrations going into the unit as much as possible, to let the transport have as much of a clean run as it can get. As you understand by now, the SB doesn't has a physical transport like that, so, putting it on isolators wouldn't be much of a difference

Skunk
2006-02-07, 08:18
Some people must make a pretty good living selling those feet. I can hardly imagine spending $400 for an interface between a table and cd player, but people certainly do.

There are lots of DIY methods you can try first to see what YOU think about it.

One is the partially inflated inner tube, with a board on top, acting as a 'seismic sink'.

Turntable manufacturers (VPI) realized sandwiching steel plate between mdf does a really good job of killing vibrations. That would be pretty easy to make yourself, especially squeezebox size.

Other people cut tennis or generally squishy balls in half, which looks incredulous.

I've seen people cut the bottoms off pop cans and mate two together with a ceramic ball in-between.

I personally haven't gotten around to trying any of these, but as you say I'm not sure one needs to with a Squeezebox. The clocking mechanisms may be candidates for dampening, but even that is up for debate probably. I just think there are lots of other tweaks concerning the SB that come before vib isolation.

pfarrell
2006-02-07, 09:05
Skunk wrote:
> Some people must make a pretty good living selling those feet. I can
> hardly imagine spending $400 for an interface between a table and cd
> player, but people certainly do.

It made a lot of sense back in the days of yore with turntables.
It makes far less sense with a CP player, but audiophiles are
not the most rational people. I can't imagine how a solid
state device with no moving parts, like a SqueezeBox, would care,
Maybe more so if you put the squeezebox on top of the speaker
cabinet. But I can believe that someone will swear that it makes
a huge difference.

If there is any real science behind it, then just floating it
on a tire tube or tennis ball is not going to help much.
You need to dampen and absorbe the vibration energy, and a spring
will just delay it. You really need something of a shock absorber.
Or a mass sprung between two or more series of springs.

--
Pat
http://www.pfarrell.com/music/slimserver/slimsoftware.html

jonheal
2006-02-07, 09:48
Skunk wrote:
> Some people must make a pretty good living selling those feet. I can
> hardly imagine spending $400 for an interface between a table and cd
> player, but people certainly do.

It made a lot of sense back in the days of yore with turntables.
It makes far less sense with a CP player, but audiophiles are
not the most rational people. I can't imagine how a solid
state device with no moving parts, like a SqueezeBox, would care,
Maybe more so if you put the squeezebox on top of the speaker
cabinet. But I can believe that someone will swear that it makes
a huge difference.

If there is any real science behind it, then just floating it
on a tire tube or tennis ball is not going to help much.
You need to dampen and absorbe the vibration energy, and a spring
will just delay it. You really need something of a shock absorber.
Or a mass sprung between two or more series of springs.

--
Pat
http://www.pfarrell.com/music/slimserver/slimsoftware.html
Well, you could suspend it in a vat of viscous fluid, or better yet, float it mid-air on magnets! You should also probably position an aluminum foil pyramid over it to reduce interference from alien sub-carrier frequencies (of course it will reduce your wireless signal strength somewhat).

(If I keep this up, I'm going to get banned from this forum. All in good fun, mates!)

Skunk
2006-02-07, 10:10
Well, you could suspend it in a vat of viscous fluid, or better yet, float it mid-air on magnets!

Don't act like you're joking. You're probably working on apperatuses like these in your shed as we speak, and wanted to gauge interest before setting the price point. Or, admit you've thought of them previously at least ;)

I agree, not that it matters, with Pat. But where do you draw the line? Do microvibrations in tube amps matter much? Not instigating, just curious : )

pfarrell
2006-02-07, 10:21
Skunk wrote:
> But where do you draw the line?
> Do microvibrations in tube amps matter much? Not instigating, just
> curious : )

Not sure about microvibrations, but lots of tubes used in
amps and guitar amps tend to get microphonic as they start
to fail. You can turn the amp on, bang gently on the chassis
and hear noise from your speakers. You know that feedback from
the speakers has to impact the sound thru the tubes.

Supposedly, good, new, tubes are not microphonic.
But I'm not so sure. The way they work is putting
charge on a grid, which controls the flow of voltage.
Moving the grid has to change the voltage, and thus
the sound.

Not sure if it is engineering or just marketing, but
a lot of audiophile tube amps weigh a ton. 90 pounds
of amp isn't going to move much, unless you have the
gain turned up to 11.


--
Pat
http://www.pfarrell.com/music/slimserver/slimsoftware.html

jonheal
2006-02-07, 10:31
Don't act like you're joking. You're probably working on apperatuses like these in your shed as we speak, and wanted to gauge interest before setting the price point. Or, admit you've thought of them previously at least ...
Hmm...maybe there are a few bucks to be made here.

CardinalFang
2006-02-07, 13:08
Skunk wrote:
> Some people must make a pretty good living selling those feet. I can
> hardly imagine spending $400 for an interface between a table and cd
> player, but people certainly do.

It made a lot of sense back in the days of yore with turntables.
It makes far less sense with a CP player, but audiophiles are
not the most rational people. I can't imagine how a solid
state device with no moving parts, like a SqueezeBox, would care,
Maybe more so if you put the squeezebox on top of the speaker
cabinet. But I can believe that someone will swear that it makes
a huge difference.

I've heard all sorts of claims that devices are microphonic, from the more obvious tubed amps to less obvious PSU capacitors. If any of it had an impact a true audiophile would have all his gear except the speakers in another soundproofed room. But then again they wouldn't be able to admire the wooden feng shui blocks under their solid state amp.

I can't see how an SB would have any form of microphony at all though, but the old SB had a slightly rubbery feel to it, so perhaps the case was slightly more absorbing of sound than the new SB3 case. Come to think of it, that display is made of glass and I swear it rings at certain frequencies....

no, only joking.

Paul

PhilNYC
2006-02-07, 13:55
With regards to solid state devices with no moving parts, vibrations will still affect the performance of a transformer. I do have some serious doubts whether the SB would be affected by these things, but I've heard DACs with large power supplies that have enjoyed some improvement with the use of things like brass cones or constrained layer platforms. How much these things have an impact is dependent on a lot of things...the component itself, the stand it is sitting on, etc.

ezkcdude
2006-02-07, 14:21
If you really want extreme vibration protection, just build something like I did in grad school. I needed to do very sensitive microindentation experiments, where accuracy down to 1 micron was necessary. As you can see the whole setup is on a large (200 lb) steel plate, which is suspended by bunjee cords on a steel frame. The tennis balls are not touching the plate, they are just there for an emergency! This kind of vibration isolation platform is cheap and provides just about the best isolation there is. I should know, because we had vibration tables, and they didn't work for us.

Edit: FYI, tennis balls and inner tubes were tried, and they didn't work either.

davehg
2006-02-07, 14:31
My personal experience is that certain isolators have worked incredibly well with turntables, and noticeably improved tube amps/preamps and some CD players. Of the various ones I have tried (those that absorb and release, those that insulate), my favorite products are the Final Labs Daruma, which use a steel or ceramic ball b/t two cups. Haven't tried but heard good things about using a heavy base supported by racquet balls or tennis balls cut in half.

I get why these devices would work in a turntable, where vibrations transmitted to the pickup device would be thereafter amplified downstream. I also get why they work in tube devices: tubes are microphonic and could amplify noise/vibration. Could the same be true with non-tube DC players? Why not? After all, these devices have amplification stages which are not immune to the effects of vibration.

Scientific studies have demonstrated that vibrations can be amplified and interfere with and obscure the original amplified signal. Check out the following articles:

http://www.rtd.com/images/movie/IDAN_VIB.PDF

I have my SB3 sitting on an old pair of Audioquest sorbothane feet, but can't say I notice any differences. My computer is not sitting on any feet, but does sit on an older target rack with spiked feet. Again, I don't notice anything, but never have tried.

Skunk
2006-02-07, 15:06
Of the various ones I have tried (those that absorb and release, those that insulate), my favorite products are the Final Labs Daruma, which use a steel or ceramic ball b/t two cups. Haven't tried but heard good things about using a heavy base supported by racquet balls or tennis balls cut in half.


Not trying to start anything, because I appreciate you sharing your experiences, but just wanted to point out something interesting I had read at Grand Prix audio's site a while back RE: bearing technology for vibration isolation.

Supposedly it was patented a long time ago for structural use under scyscrapers in earthquake prone areas, but was abandonded for 'spring and viscoelastic*' damping (1).

The link also does a good job of making Solid Steel brand turntable racks seem utterly backwards.

(1) http://www.grandprixaudio.com/idx_design_wp.htm
(*) See Jon, you were on to something : )

CardinalFang
2006-02-07, 15:13
With regards to solid state devices with no moving parts, vibrations will still affect the performance of a transformer. I do have some serious doubts whether the SB would be affected by these things, but I've heard DACs with large power supplies that have enjoyed some improvement with the use of things like brass cones or constrained layer platforms. How much these things have an impact is dependent on a lot of things...the component itself, the stand it is sitting on, etc.

I partly understand the logic behind these things since these devices attempt to insulate the transmitted vibrations from the surface below, but surely most interference is airborne - the audio itself - so how can isolating cones help out here? A tube in free air is always going to pick up vibrations through the pressure waves, even if it doesn't get the ones from the furniture it's sitting on. Let's face it, you can feel the bass in a good system, so how on earth do you stop that shaking the tubes and components in the stereo with some isolating platform?

I also accept that the sense behind some of this is the tiny movements of wires due to vibrations, especially in point to point wiring. If there's any sort of magnetic field around, then currents will be induced by the vibrations too. If these wires are inside the boxes of the amp and therefore shielded from the sound pressure waves to large extent, then isolation should help there.

Paul

Deaf Cat
2006-02-13, 02:47
Interesting comments, plenty of areas for experimentation/playing, but maybe not with the SB on this occasion, for me anyway.

Feel a little more enlightened now, cheers!

radish
2006-02-13, 07:36
As a related aside, in a lot of clubs the dj console/booth is built up high, often with a large stack of speakers (or better yet, bassbins) directly below it. This vibration doesn't just transmit through the needle of the turntables, it can make the whole arm jump up and skip a quarter inch. Not really useful! Many larger clubs have fitted isolation platforms which resemble a steel plate mounted on a number of car shock absorbers. The contraptions are huge and heavy but they do the job very well. I don't think they'd get a very high WAF though :)

russj
2006-02-26, 04:39
Isolation makes no difference to the sound in the real world (turntables excluded for obvious reasons). It might do in a dedicated listening room or in a lab, but in the real world its just not worth it. The differences if any are so minute that they are not worth striving for. I've been there with my audiophile hifi which i've slimmed down to just amps speakers and a squeezebox. All the expensive cables, CD transport and DAC, milimetere perfect positioned speakers and accoustic damping have bit the dust. Some of the things we audiophiles do to try and improve the sound quality is crazy, and when you find yourself testing music between different cables, or blue-tac under the speakers vs 150 titanium cones, desperately trying to detect a difference, well it smacks of psychological instabillity to me. I decided to listen to the music intead of being obsessed by sound quality. When it comes down to it, audio equipment doesnt need tuning, its great out of the box. Just find a setup you like the sound of and get on with enjoying your music.

ezkcdude
2006-02-26, 08:40
Isolation makes no difference to the sound in the real world (turntables excluded for obvious reasons). It might do in a dedicated listening room or in a lab, but in the real world its just not worth it. The differences if any are so minute that they are not worth striving for. I've been there with my audiophile hifi which i've slimmed down to just amps speakers and a squeezebox. All the expensive cables, CD transport and DAC, milimetere perfect positioned speakers and accoustic damping have bit the dust. Some of the things we audiophiles do to try and improve the sound quality is crazy, and when you find yourself testing music between different cables, or blue-tac under the speakers vs 150 titanium cones, desperately trying to detect a difference, well it smacks of psychological instabillity to me. I decided to listen to the music intead of being obsessed by sound quality. When it comes down to it, audio equipment doesnt need tuning, its great out of the box. Just find a setup you like the sound of and get on with enjoying your music.

Well, I guess we don't need an "Audiophile" forum, after all ;)

Pale Blue Ego
2006-02-26, 11:19
I do use a bit of "museum putty" under my zinc-alloy speakers in the (Aego2) 2.1 bedroom system, to keep them positioned precisely and to keep any small vibrations from affecting the shelf the SB3 sits on.

I didn't do any special listening tests before and after, but I continue to be very pleased by the sound of that system.

The Aego2 system really seems to be a great match for the SB. It's a shame they don't have a U.S. distributor anymore. Their new AegoM 2.1 system even has rounded corners that would look great with the SB3