Vibration isolation or absorption?

Spikes do not isolate, they couple.

Back in the 1970s and earlier, loudspeakers were often fitted with rubber feet that sensibly decoupled them to a degree from the surface they were placed upon.

Then, some time in the 1980s some reviewers began to try out spikes under their speakers. Before too long a whole sub industry had appeared, all on the words of a few reviews.

Such was the esteem the printed press had back then.

A decade or so later, enthusiasts such as the late Max Townshend began to experiment with decoupling loudspeakers from their surface, the same as the rubber feet had done previously, only to a far greater extent.

Only this time they had irefutable accelerometer data to back up their opinions. Lots and lots of it.

And so, here we are again in the present day, with decoupling now rapidly becoming the accepted norm once more. There are now literally dozens and dozens of manufacturers offering various form of decoupling products.

As they say, 'what goes around comes around'.

@soix https://www.amazon.com/Tertullus-Isolation-43mm%C3%9738-5mm-Aluminum-Turntable/dp/B09QC1DJXT/ref=sr_1_6?crid=3O9WPNIK3HIXK&keywords=speaker+isolation+pad+spring&qid=1680557813&s=electronics&sprefix=speaker+isolation+pad+spring%2Celectronics%2C143&sr=1-6

That isn't the brand I bought but those look the same.  Mine were from Audiocrast or something like that.  My Legacy center channel weighs 65lbs or there abouts, so I used all of the supplied springs.  If you have lighter speakers, just take some springs out.  There are 6 on the outside and 1 on the inside.  So you could run with as little as 3 for lighter weights.  As I understand it, you want them to sink down around ~50% in an effort to load them.

I should add that similar ones are under my 3" maple block turntable isolation platform (in my profile pics).  I think I used 12 for under it because that block and the VPI Classic are so damn heavy.  I also use 4 under my server.  They work killer for that because servers vibrate like crazy with all of the fans, spinning HDDs and stuff.

@audiom3 Hey thanks a lot man! I’m a long way from buying Seismic due to budget constraints, but I bet these give a good bit of what they do given your stated results at a fraction of the cost (they are springs too after all), and the fact that you can custom tune them by removing springs is WAY cool. Given how vibration along with noise is the mortal enemy of streaming sound I’m excited to try these.  Thanks for introducing us to them!

@larryi nailed this from the first sentence:

Like almost everything involving vibration damping/control, it is a matter of tuning, so there is no definitive answer. 

I would add that there is also an associated component of personal preference.

@atmasphere eloquently added to the technical nature of the discussion:

I view this as 'points vs squishies' - Points are used to move vibration into the mass to which the point is pointed...Squishies are used to isolate

I have used many types of both points and squishies, starting with spikes and points early on, both on suspended wood floors and on concrete slabs on grade, and then in the past couple of years migrating toward being a fan of squishies, which are in essence a damped spring.  Vibration control is often modeled using springs and dampers. Damped springs are used for isolation of items ranging from delicate laboratory instruments to heavy duty industrial machines.  Your car has springs and shock absorbers (dampers). 

Years ago, you could read on this forum about folks using hockey pucks to "decouple" their speakers (fwiw - spikes were mostly referred to as providing coupling while everything else was referred to as decoupling). Former A'gon member Geoff Kait (i.e., Machina Dynamica) used to promote and sell springs for use under electronics and speakers, as did @millercarbon later with Townshend.  I tried using springs myself with some success under my electronics and under my two 160-pound subs and 170-pound speakers, both including their dedicated SA stands.  I studied what Townshend and Credo Audio were doing and damped the springs, but getting the size, travel, and spring constant properly sized for the weight supported and the isolation frequencies desired required a bit of trial and error.  As a result, I have a box of springs. 

I then switched to elastomeric materials (in essence another type of damped spring) and was pleased with the sound I was hearing when using products from Herbie's Audio Lab that are custom designed for different types and weights of electronic equipment and speakers, and are much less expensive than the spring solutions by Townshend or Credo.  The Herbie's dBNeutralizer material in their speaker support products is a harder elastomer with hardness (based on Shore A durometer - how hardness of an elastic material is measured) of 70 (quite a high number), which doesn't really compress much.

More recently, I have found other (much less costly) elastomeric products by Hudson Hi-Fi, that are available on Amazon.  Their products are made from platinum silicone.  BTW, the Herbie's products are also made from a silicone material.  I recently started using the Hudson Hi-Fi Silicone Hemisphere Bumpers under my main speakers and subs.  They conveniently provide the weight ranges supported by each sized hemisphere.  Since they are all a softer hardness of 20 (Shore A durometer), you need to go up in size to the larger products to support more weight.  I used their 2.5-inch size under the front of my speakers and the 2-inch size under the rear.   This worked out great since the weight of the drivers is in the front making the weight in the front of my stands heavier than in the back.  In addition, the speaker manufacturer recommends a slightly sloped front to back orientation so having slightly larger footers in the front was perfect.  You can simply stick the bumpers to the bottom of your equipment or speakers (which I have done with smaller power supplies and other ancillaries) but taking a cue from Herbie's, I attached the flat bottom of the bumpers to Magic Sliders and put the slider side down, which helps with sliding and positioning on carpet over concrete.  The result provides a much closer approximation to a damped spring than I had with the Herbie's products.  The speakers can actually move, as they could with the springs but they are damped so that when excited they become stationary after only a few oscillations.  They sound good so far under both my main speakers and under my subs (4 each at 2-inches).  Consider your options - YMMV.