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'.

@jumia 

So don’t you want to draw that vibration away and channel it somehow into a bottomless pit. Shouldn’t the pointy things, aKA spikes, funnel the vibration onto A disc pucky thing that will make the vibration go away.

Why would you want to isolate vibration and have a rebound back-and-forth all over the place within a speaker, or component?

Audio is full of these apparently logical contradictions but upon closer inspection we usually find that one or another of our preconceptions is faulty.

This has happened to me many, many times. And not just in audio

First of all we should consider whether it is possible to channel away vibration with something as solid as a steel spike.

Or could it be that the spike actually couples the speaker cabinet to the supporting surface and sets up further resonating mechanisms?

Isolating vibration by decoupling fundamentally lowers both the resonant frequency and its strength between cabinet and surface.

Both of these are good things, especially when the resulting resonant frequency is lower than the bass output of the speaker. For example something like 20Hz, which most speakers can't get close to, would be good and anything lower would be even better.

I'm pretty sure that the Townshend devices go considerably lower than 20Hz.

For me, the missing piece in this puzzle is the notion of constrained layer damping. I've read that it's superior to using springs alone but I can't remember why that is so.

Perhaps someone could chime in with why CLD is theoretically considered superior?

@jumia 

Is vibration a two-way street?

So you have vibration from a speaker cabinet, but don't you also have vibration due to the sound waves bouncing around the room where the floor will vibrate and that vibration will transfer back into the speaker cabinet and also the component rack?

So maybe isolation is the answer?

Yes, you have all kinds of vibrations.

However I believe that the most serious ones are those usually coming from the loudspeaker cabinet itself.

Accelerometer tests have revealed that the loudspeaker baffle can be vibrating at far greater levels when that loudspeaker is placed on spikes as opposed to when it has been decoupled via springs or rubber.

Perhaps we could imagine the loudspeaker drivers acting like musicians standing on a vibrating floor? The less that 'floor' vibrates throre chance they have of performing with greater accuracy.

Of course there will be other vibrations that might affect the floor also but the ones coming from inside the box must surely be the most serious when it comes to smearing the sound.

It should also be noted that these days an increasing number of loudspeaker manufacturers are using laser inferometry to design their cabinets in order to limit these vibrations from acting on the loudspeaker baffle.

And then there's the thin walled BBC approach as used by the likes Harbeth, Spendor and Graham Audio.

The days of loudspeakers with terrible 'waterfall' graphs revealing poor construction seem to be over.

However, since my Tannoy speakers are over 40 years old, I'm not too surprised to find that decoupling works for me. Back then, the BBC research into cabinet construction had barely been published.

@audiopoint 

We also have a right to use AudioGon for advertising or promotional purposes as we pay a monthly fee to their advertising programs. There are a host of dealers, manufacturers, and reviewers doing this on all forum-based businesses. Some of them hide behind the smoke and others come forth and admit it. Either way, marketing is like vibration, it is everywhere.

Wow, I almost had to do a double take!

Such candidness is unlikely to make many friends but it is certainly refreshing to see such honesty in a public forum.

As for your statement :

I was ridiculed, called stupid names, and took everything the members dished out.

In my opinion, the High-End Audio Industry is hesitant to accept change or new advancements in technical achievements until there is advertising money involved.

That sounds about right too (just check out some of the recent ASR threads).

This open approach is no doubt the better way to do business. For that I wish you continued success. It's only fair and right that the customer deserves sympathetic respect and not routine deception.

It's quite amazing how the market for decoupling products has grown to such an extent in such a short time. We're now even seeing lossy decoupling being built in to products such as the Q Acoustics Concept range of loudspeakers.