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Coupling/Decoupling Electronics

All the posts I’m making are due to my recent purchase of KEF LS50s and my attempts to optimize them. I’m now the first to admit that little changes make a big difference. At 12” from the wall behind then, the bass gets a little muddy. At 13”, I get nice reinforcement without any muddiness. A couple of weeks ago, if you had told me that an inch would make a difference, you’d get a very skeptical look. 

Inevitably, I wandered into the coupling/decoupling, spikes/pads battle. After much reading and a lot of lessons in physics-lite, I have determined that there are too many variables at work—speakers, stands, carpets, floors—for any kind of blanket statement to be made. 

There seems to be less controversy about electronics. The word is: Isolate! Those same speakers that are producing so much vibration are a deleterious force. We must do our best to keep those vibrations away from our finely tuned electronics. 

So here is my question: Don’t electronics produce their own vibration? CDs spin, amplifiers amp. Lots of energy being produced. Like speakers, is isolating them from the world around the right thing to do? Shouldn’t that energy inside the boxes be passed off, as speaker energy is passed off by spikes?


I suspect that, like the speaker question, there’s too many variables at play for a simple answer but I thought I’d ask.


Here’s another, more mystifying question. I just traded up from KEF Q150s. Black ones can be had for $300 from Amazon. White ones—the identical speaker—are out of stock everywhere and cost $5-$600 if you can track down a pair. This seems not to be an example of an efficient market, as Adam Smith might define it. (I’m not complaining. I had white ones.) (And I think that Adam Smith’s ideas are long out of date, having been surpassed by managerial capitalism, advanced capitalism, and whatever is en vogue at this University of Chicago these days.)
paul6001
lowrider57's avatar
lowrider57
5,417 posts
 
Yes, components do produce their own vibration. Usually the stock footers don’t provide enough isolation and don’t drain vibration from the component. The component can also pick up acoustic energy from the speakers and vibration from the rack/furniture.

Two schools of thought are to either drain vibration into a platform by using cones or spikes placed under the component. The platform is often a hardwood such as maple and is isolated from the shelf. There are many audio racks which have shelves which provide their own isolation.

Or by decoupling; devices are used to isolate the component from it’s environment and also absorb vibration. Decoupling devices include footers that absorb the vibrations, platforms and shelves designed to isolate the component, placing springs underneath, and shock absorber type footers.
This is only an overview of techniques.


antigrunge2
1,415 posts
 
Component vibrations, unless airborne, tend to emanate from power supplies. These not only vibrate but also generate EMI. The most effective way I have found for draining these is to use a combination of Black Ravioli pads with isolating footers (Stillpoints, Black Racing Cones et all). Use them under the chassis, not the component’s footers, though. Against EMI I found Acoustic Revive REM-8 highly effective.
chayro
2,995 posts
 
I agree with the above posters about draining vibrations and all, but always keep in mind that ultimately you may prefer the sound of the component sitting on it's own feet.  In some cases, putting footers or platforms under the component may harden or soften the sound in a way that is not pleasing to your ear.  So IMO, it's a good idea to try these things, but always put your musical preference above the intellectually-appealing concept of draining the vibrations out of a component.  
erik_squires
16,116 posts
 
Speaker energy is not passed off by spikes.  Spikes minimize the contact area to the floor, making transmission harder vs. full surface contact. Richard Vandersteen wrote an excellent article on the subject on his blog.
mahgister's avatar
mahgister
13,091 posts
 
I use with great success springs sets finely adjusted on top of a sandwiches of coupling/decoupling varied materials: bamboo,granite,cork,sorbothane....

I use 2 sets of 4 springs boxes dyssemetrically compressed by some heavy load damping the speakers and the 2 sets of 4 springs boxes for each speakers one set under the load and another set under the speakers+the load.... Natural timbre of instrument and minimal interference between speakers sitting on my desk.... Cost: peanuts...
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