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How much difference do Speaker Stands make?

Purite Audio said:
I really don't know where to begin, but 'cabinet bottom bouncing audibly ' made me smile.
Keith.
Click to expand...

Good. It was tongue-in-cheek. :)

Can't begin? Let's try one step at a time.

First, I divide vibrations into wanted and unwanted. With me so far?

Second, I claim that unwanted vibrations can be 'killed.' That is casual and informal speech, I am aware that vibrations are energy, and energy can neither be created nor destroyed, it can only be changed in form. But am I right that vibrations 'go away' when they dissipate into the material through which they pass--becoming the sort of vibration we call heat? Is that not their general fate?

That should be enough for this go.
 
Ragaman said:
For every action in nature, there is an equal & opposite reaction... Newton.

The only way to prevent vibration hitting a stand is to use sorbothane, if you couple, the vibration is transmitted to the floor, via the stand, & then back into the stand, then into the speaker, however well damped the stand, over damping speaker cabinets can result in a very dull, lifeless sound, same with room acoustics. Designers usually have the edge when dealing with such matters, best to pick a speaker because you enjoy the sound it makes rather than get bogged down with if it's damped well enough.
Metal stands create subtle changes as with most accessories, they are mostly designed to have a certain effect on a speaker, i prefer a more neutral aproach but i can see why many enjoy the more forward, forced presentation metal stands add to the mix.
Click to expand...

Can the cabinet not be said to be coupled to the sorbothane, if it is used?

A vibration hits the sorbothane from the cabinet. Then what happens?
 
DonQuixote99 said:
A vibration hits the sorbothane from the cabinet. Then what happens?
Click to expand...
"Spikes act like as springs. Very rigid springs.
The combined effect of Mass ( speaker) x springs = Resonant Frequency normally located in the 1-3 Khz.
This is bad because the system work in elastic reaction. The system is coupled below the FR and decoupled above Fr.
The woofer shake your floor and viceversa.
Diodes do not exsist in mechanic .
If you want seryously decoupling all the frequencies 20-20000Hz
you must employ a subsonic FR ie employ a very soft souspension,
ideally below 5Hz with the minimal damping (important).
In this case the system works in inertial reaction.
The souspension filter the armonic spectra of the reaction that the floor act to the speakers movements. This is good because you minimize the exchange forces (vibrations) and maximise the immobility in the audio band.
Yes the speaker float but it is near immoble in the audio band.
Best method to obtain this are air spring or use long elastics from the ceiling ( bad WAF )
You can solve all your problem of vibrations , as like every Lab in the worlds do : air spring or elastic cables tuned subsonically.
see this article

http://www.stereophile.com/reference/52/index.html

or search " damped armonic oscillator "- principle

hope this can help

cheers,

Paolo"
 
murphythecat said:
"Spikes act like as springs. Very rigid springs.
The combined effect of Mass ( speaker) x springs = Resonant Frequency normally located in the 1-3 Khz.
This is bad because the system work in elastic reaction. The system is coupled below the FR and decoupled above Fr.
The woofer shake your floor and viceversa.
Diodes do not exsist in mechanic .
If you want seryously decoupling all the frequencies 20-20000Hz
you must employ a subsonic FR ie employ a very soft souspension,
ideally below 5Hz with the minimal damping (important).
In this case the system works in inertial reaction.
The souspension filter the armonic spectra of the reaction that the floor act to the speakers movements. This is good because you minimize the exchange forces (vibrations) and maximise the immobility in the audio band.
Yes the speaker float but it is near immoble in the audio band.
Best method to obtain this are air spring or use long elastics from the ceiling ( bad WAF )
You can solve all your problem of vibrations , as like every Lab in the worlds do : air spring or elastic cables tuned subsonically.
see this article

http://www.stereophile.com/reference/52/index.html

or search " damped armonic oscillator "- principle

hope this can help

cheers,

Paolo"
Click to expand...

What is that, something from the common book of prayer? Everyone says the same words together, amen?

Does some bit in that answer the question I asked?

ON EDIT: now see your second answer, and will look at what you linked to.
 
OK murphycat, on what I read of that thread, 'Inertial' posted what I just named the 'common book of prayer' material above, asserted that what other people posted was wrong, asserted his authority of knowledge and nothing else, and got huffy. I'm not totally convinced yet....
 
DonQuixote99 said:
OK murphycat, on what I read of that thread, 'Inertial' posted what I just named the 'common book of prayer' material above, asserted that what other people posted was wrong, asserted his authority of knowledge and nothing else, and got huffy. I'm not totally convinced yet....
Click to expand...

you havent read the whole thread, nor the stereophile link where everything he says is explained, nor read about inertia reaction.

edit: "common book of prayer", you mean law of physics and mechanics? because that what inertia is talking about. he is nowhere wrong about anything he says.

"The speaker work in dynamic regime 20-20K , not static!
To be immovable mean absence of relative movements ( ie vibrations) IN BAND of work .
A spiked loudspeaker can have a FR normally 1-4khz.
It means that the floor oppose his elastic reactions to the speaker's movements for frequencies below FR where they are integrally transferred INCREASING the total vibrational capability ( amplitude and spectra) ie loosing the relative immobility and decreasing the
dinamycal rigidity of the system.
One more the propries modes of the spikes ADD to those intrinsecal of the speaker .
Forget now you are shaking the floor, the other speaker, and your
delicate tube electroincs and source.
To be complete, the "solid floor" is a poor dynamically rigidity element: a flat panel have infinite numbers of vibrational modes!"

but really, he is also right, just try it yourself. use spikes or try to couple the speakers to a stand, then touch the stand and see how much it vibrates. then change stand for a more massive stand and touch the floor and stand, then put sorbothane or subsonic suspension and touch again. then have a listen. with a subwoofer its even more evident how much decoupling is useful
 
murphythecat said:
you havent read the whole thread, nor the stereophile link where everything he says is explained, nor read about inertia reaction.

edit: "common book of prayer", you mean law of physics and mechanics? because that what inertia is talking about. he is nowhere wrong about anything he says.

"The speaker work in dynamic regime 20-20K , not static!
To be immovable mean absence of relative movements ( ie vibrations) IN BAND of work .
A spiked loudspeaker can have a FR normally 1-4khz.
It means that the floor oppose his elastic reactions to the speaker's movements for frequencies below FR where they are integrally transferred INCREASING the total vibrational capability ( amplitude and spectra) ie loosing the relative immobility and decreasing the
dinamycal rigidity of the system.
One more the propries modes of the spikes ADD to those intrinsecal of the speaker .
Forget now you are shaking the floor, the other speaker, and your
delicate tube electroincs and source.
To be complete, the "solid floor" is a poor dynamically rigidity element: a flat panel have infinite numbers of vibrational modes!"

but really, he is also right, just try it yourself. use spikes or try to couple the speakers to a stand, then touch the stand and see how much it vibrates. then change stand for a more massive stand and touch the floor and stand, then put sorbothane or subsonic suspension and touch again. then have a listen. with a subwoofer its even more evident how much decoupling is useful
Click to expand...

First of all, i have not suggested using floor spikes. I''m open to well-explained rationales for anything, and it might work sometimes, but basically, no, I don't think I want to transmit vibrations to the floor. So all the discussion of the bad effects of floor vibrations are not on point with me.

I'll be happy to pursue more knowledge in the future, perhaps through study of the sources you suggest. But since we're in contact, it might be constructive if we could just share our own thought. With that in mind can you explain what happens when a cabinet bottom, in close and snug contact (coupled, one might say) with sorbothane applied as specified, emits a vibration?
 
DonQuixote99 said:
Can the cabinet not be said to be coupled to the sorbothane, if it is used?

A vibration hits the sorbothane from the cabinet. Then what happens?
Click to expand...
I would contact Kieth for that explanation.
All i know is, when rapped with a knuckle, there are no vibrations traveling to the stand & vice versa so something must be right.
 
visco elastic material, trade name Sorbathane is essentially open cell rubber, rubber with air bubbled through it .
Vibration is absorbed by the material it is not a spring, closed cell rubber would be a spring.
You have to trust that the loudspeaker designer has made a good job of designing the enclosure so that it doesn't store energy ,which will lead to resonance and colouration of the sound.
Isolating/decoupling may stop the transmission of sound to your downstairs neighbours.
That's it .
Keith.
 
How do you know if the speaker does store energy & how would you deal with this. My Castle speakers are well damped, wood veneered inside & out with bitumen pads fitted, also, the cabinet is like a piece of solid furniture, no surprise as Castle, back then, started out as cabinet makers. My mordaunt short speakers are not so lucky but are reasonably solid.
Let's say Kieth, you have no option but to purchase a stand for your speakers, what stand would you go for, to allow your speakers to work as best they can under the circumstances & what kind of support would you go for if you have a carpet, i can see no alternative to spikes, it is the only way any stand can remain stable in our room.
 
Purite Audio said:
Isolating/decoupling may stop the transmission of sound to your downstairs neighbours.
That's it .
Keith.
Click to expand...

But it must surely also change the measured in-room frequency response and/or reverberation time, otherwise why would people be reporting sonic differences with and without sorbathane?
 
My speakers sound quite different with atacama gel pads compared to oak cones, it is undeniably different, even Kieth would hear this one.
What i still find odd is this, my particular stands have 3 columns, 2 unfilled columns at the rear, 1 partly filled at the front, if i rap my knuckle against the rear (with speakers sitting on gel pads) the delay time of the ringing lasts far longer than when sitting on oak cones, the ringing disappears in around half the time, what is the explanation for this time delay, i would have thought the gel pads would have soaked up this ring, it puzzles me why the ring lasts far less with the cones underneath the speaker.
The only explanation i have is, the ring is traveling through the stand quicker to the floor, with gel pads in place, it may be slowing down the vibration reaching the floor so could be doing more harm than good, maybe it's better to have everything coupled to make sure any vibration travels as quickly as possible away from the speaker into the floor via spikes, even if some vibration may get back into the stand, obviously from this, the ringing is disappearing faster so could be a better idea.
It could explain why i favour the sound of my speakers on the oak stands as any vibration will travel through wood much faster than metal, i would imagine metal would slow this process down compared to wood, any vibration will travel a faster speed into the floor, where metal would store the energy for a longer period, which could be detrimental to sound quality, especially at higher volumes.
 
John Atkinson carried out some tests for Stereophile where he used different materials between speaker and stands, there were small differences in the waterfall plots of the speakers using the various materials.
If you 'stick' a loudspeaker to a high mass stand you will lower the resonant frequency of the loudspeaker.
Depending upon the floor type/construction , the frequencies transmitted you might be able to generate an audible resonance, I believe isolation is good as long as it doesn't make the speakers physically unstable.
Keith
 
Ragaman said:
My speakers sound quite different with atacama gel pads compared to oak cones, it is undeniably different, even Kieth would hear this one.
What i still find odd is this, my particular stands have 3 columns, 2 unfilled columns at the rear, 1 partly filled at the front, if i rap my knuckle against the rear (with speakers sitting on gel pads) the delay time of the ringing lasts far longer than when sitting on oak cones, the ringing disappears in around half the time, what is the explanation for this time delay, i would have thought the gel pads would have soaked up this ring, it puzzles me why the ring lasts far less with the cones underneath the speaker.
The only explanation i have is, the ring is traveling through the stand quicker to the floor, with gel pads in place, it may be slowing down the vibration reaching the floor so could be doing more harm than good, maybe it's better to have everything coupled to make sure any vibration travels as quickly as possible away from the speaker into the floor via spikes, even if some vibration may get back into the stand, obviously from this, the ringing is disappearing faster so could be a better idea.
It could explain why i favour the sound of my speakers on the oak stands as any vibration will travel through wood much faster than metal, i would imagine metal would slow this process down compared to wood, any vibration will travel a faster speed into the floor, where metal would store the energy for a longer period, which could be detrimental to sound quality, especially at higher volumes.
Click to expand...

Was this test done with the gel pads and oak cones on wooden stands or metal stands? Also, how are the oak cones coupled to the stands, double-sided tape?
 
ToTo Man said:
Was this test done with the gel pads and oak cones on wooden stands or metal stands? Also, how are the oak cones coupled to the stands, double-sided tape?
Click to expand...
Metal stands, as i said, the rear columns ring when rapped, the oak cones were attached to the underneath of the speaker with point down (double sided tape, 2 at the front 1 at the rear), at first i thought maybe the speaker is soaking up the ring (rather than the vibration travelling down into the floor more quickly) obviously this is wrong as the gel pad would effectively stop the ring entering the speaker from the stand. Puzzles me why the ring lingers on for much longer with gel pads fitted. I can only think my explanation above may be correct.
Having counted this, with cones, 2 seconds, with gel pads around 5 to 6 seconds, with cones it comes to a sudden stop, with pads it fades out to silence, something must be going wrong where the gel pads are concerned, i feel they may be slowing down the vibration, storing it in the stand for longer, which cannot be good.
I also have to admit, having just switched between the two options, with cones, the sound is far more solid & defined, with pads, the sound does sink back a little, sounds a little lacklustre by comparison, odd. Some of the urgency disappears.
 
Ragaman said:
Metal stands, as i said, the rear columns ring when rapped, the oak cones were attached to the underneath of the speaker with point down (double sided tape, 2 at the front 1 at the rear), at first i thought maybe the speaker is soaking up the ring (rather than the vibration travelling down into the floor more quickly) obviously this is wrong as the gel pad would effectively stop the ring entering the speaker from the stand. Puzzles me why the ring lingers on for much longer with gel pads fitted. I can only think my explanation above may be correct.
Having counted this, with cones, 2 seconds, with gel pads around 5 to 6 seconds, with cones it comes to a sudden stop, with pads it fades out to silence, something must be going wrong where the gel pads are concerned, i feel they may be slowing down the vibration, storing it in the stand for longer, which cannot be good.
I also have to admit, having just switched between the two options, with cones, the sound is far more solid & defined, with pads, the sound does sink back a little, sounds a little lacklustre by comparison, odd. Some of the urgency disappears.
Click to expand...

I was thinking of testing this for myself (felt vs blu tack vs sorbathane pads vs wooden cones), but I currently only have metal stands to hand (Atacama SE12, SE20 and SE24, all of which are 100% sand-filled). I keep meaning to buy a pair of wooden stands but am concerned about their stability (the less expensive models from the likes of HiFi Racks look as if they would wobble on carpet). There's also some interesting options on eBay. Mind if I ask where you got yours?
 
Purite Audio said:
visco elastic material, trade name Sorbathane is essentially open cell rubber, rubber with air bubbled through it .
Vibration is absorbed by the material it is not a spring, closed cell rubber would be a spring.
You have to trust that the loudspeaker designer has made a good job of designing the enclosure so that it doesn't store energy ,which will lead to resonance and colouration of the sound.
Isolating/decoupling may stop the transmission of sound to your downstairs neighbours.
That's it .
Keith.
Click to expand...

Ah, it kills vibration then. Good!

Can you explain more what is meant by saying a loudspeaker 'stores energy,' in those cases where that happens?
 
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