Best spikes position under loudspeaker

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Frank Lloyd Wright designed some office chairs with two legs at the back and one at the front, knowing they would be unstable, in order to promote good balanced posture.

After the requisite number of spills he relented to the stability of four points of contact.

Not such an issue if nobody sits on the speakers I suppose.
 
Good line of thought but all wrong. Think "cones" instead of speakers. You want the cones to move accurately relative to the cosmos (or least relative to your head). And that requires that their baskets (and box) be firmly defined in space.

Any speaker motion is parasitic and should be inhibited, not sprung.

Advocates for electrostatic speakers will intuit another important advantage for their systems in this analysis (ahem, ahem).

B.

Totally and completely wrong. There are only two options for what you can do with reaction forces. Dissipate or propagate. Both involve movement of the enclosure.

To propagate implies introducing the floor as a sound board. You don't want to do that.

You want to dissipate so that the total enclosure, and only the enclosure, absorbs the reaction forces. This will lead to some movement of the enclosure, but this will still be very small compared to the cone movement.

Also with spikes, the enclosure will still move, albeit perhaps a bit less, but now you will transfer the reaction forces to the floor, which will vibrate as a result and which by its nature will be very efficiently acoustically coupled to your room.

Your advise should not be followed.
 
Totally and completely wrong. There are only two options for what you can do with reaction forces. Dissipate or propagate. Both involve movement of the enclosure.

To propagate implies introducing the floor as a sound board. You don't want to do that.

You want to dissipate so that the total enclosure, and only the enclosure, absorbs the reaction forces. This will lead to some movement of the enclosure, but this will still be very small compared to the cone movement.
An excellent example of medieval style argument* but all wrong.

You don't want sensible MOTION of the enclosure (or floor, of course).

B.
*"There are only two......"
 
I thought the idea of spikes was to provide a rigid but at the same time almost non existent coupling due to the small as possible contact area? Does appear to me to be a bit contradictory?

You are exactly right about that being contradictory. Spikes provide the best possible coupling between enclosure and floor. This visual analogy illustrates what spikes do:

bridge.jpg
 
For find the right solution, we need before.. understanding what are spikes and them.
mechanical vibrational Engineering knows well, what is the comportament of a spikes alone or inserting in a structure composite.
The spikes all are springs, each spike have own resonance frequency determinated from shape and material.
A spike metal made will have a high resonance frequency,
at the opposite way the rubber or any material configurated for obtain a low resonance frequency..
When you put a metal spike under the loudspeaker you add the vibrational mode at the resonance frequence, if we listen a more cleaned sound is because we have add and amplificate the sound in corrispondance of the spikes resonance frequency.
If you put a metal spikes under loudspeakers Which has a clean sound, a balanced sound well, we will listen a bass depletion.
If you want see what happen when you add a metal spike or any other material, you can use an accelerometer.
And... many wrong concept for describing louspeakers behaviour.. will be delete.
one for all,
"the spike that discharge the vibration".. is a heresy, is a invention give birth from a deep ignorance and lack of the basilar knowing.
 
Go ahead !
You do fine by not tellin us of which material, thickness, geometry the cabinets are made.

It must be real secret, except fatty wives :rolleyes:

:dunno:

By putting an accelerometer you ( if you can, i.e. putting the system-s- in isolation ) just measure the external vibrations, the Z result of forces that happen to be there when a material is solicited to vibrate in its own modes..
There's another topic during these days goin on...

But that goes not deep into the subject of the ( cabinet)( sub-) system that
is subjected to forces .

Mostly, is the woofer ( why ? ) that produces them, so, for istance, why not put the other drivers in isolation ( if that condition is wanted and prosecuted ) ?
 
You are exactly right about that being contradictory. Spikes provide the best possible coupling between enclosure and floor. This visual analogy illustrates what spikes do:

View attachment 626437

Are you sure? The bridge of a stringed instruments serves as a coupling medium between the oscillating string and the sounding board of the instrument's body. Do you really want to transfer energy from the speaker's cabinet to your room's floor via spikes?

Best regards!
 
Are you sure? The bridge of a stringed instruments serves as a coupling medium between the oscillating string and the sounding board of the instrument's body. Do you really want to transfer energy from the speaker's cabinet to your room's floor via spikes?

Best regards!



No, I don't, but some people do. I showed this because I consider spikes to be a downright stupid idea.
 
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