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 (And I think that Adam Smith’s ideas are long out of date, having been surpassed by managerial capitalism, advanced capitalism, and whatever is en vogue at this University of Chicago these days.)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

Showing 1 response by oldhvymec

Points isolate in one direction. unless they are setting on a bed of springs, and then you have to dampen the springs, they will ring..
The problem is the box.. It is alway the enclosure and the width of the baffle face. Its ability to deflect waves coming BACK and waves from inside. You can isolate the internal waves but the box resonance.. That requires some thinking..  Rounded corners, panel breaks, and surface treatment inside and on the way out, is the best way. 

Springs, airbags, earthen foundation, flotation, magnetic repulsion, suspensions and ALL types of devices still leave THEIR mark on the sound... It really depends whether you like it or not.. The simpler the better for me.. Heavy, thick, quiet, enclosures work..

Remove ALL the unwanted resonance by removing the drivers from the enclosure. That is the only good way.. Everything else is a compromise.
Once you understand that you can build a DIFFERENT type of system..
Things like boundys become a lot less of a problem just like driver time alignment and phase shift. ALL the gobbledegook, like filling the room with ugly ass acoustical STUFF becomes a lot easier. I use separate narrower columns NOW.. Just works better.. It is a work in progress..
Just not an UGLY one.. 

Like I said before, "she can only be so ugly" (or he if you prefer) and they will get a bag over the head.. Put some lipstick on the bag I'm fine.

Regards