Vibration Theory - Isolate or Drain?


Given that a CD Player or Transport has quite a bit of internally generated energy from the motor, is it best ti deal with vibration issues by coupling the player to a surface with spikes or cones? or decouple the player from the surface beneath it with spongy materials? Any consensus on the best approach here?
pubul57
Joe Grado in 1984 supplied his $50 cartridge with a free small triangular mount with 3 small protrusions that set between the the body and the headshell. Better coupling more sound.
Tom
I have recently coupled my system so that all components are tied to my rack to drain and WOW it does make a serious improvement. It's called RTS Coupling from Audio Horizons. Over they last 20 years I have tried many ways of controlling vibrations including Herbies, Nordost, Eichman Toppers and many more. The improvement from coupling is 20 fold to any other device I have ever used. I only listen to CD's and what I have noticed is more micro information, more body, sense of ease, more dynamics, more of everything good and nothing bad. A very inexpensive way of making a HUGE improvement to any system.
Addressing your initial question about isolating/damping CDP against vibratipn, I do both. In the few CDPs over the past 23 years, I’ve dampened the chassis with rope caulk or Mortite. I started using Mortite on the underside of my Denon t-t back in the late 70s with good results, so I was anxious to use that on the CDP. IME, all aspects of the sound improved. I also isolate the CDP using Symposium Rollerblocks which further improve the sonics.

Try the rope caulk. It will cost less than $10 to do your whole player.if you don’t like the sonics,simply remove it.
The Mortite idea is interesting. Any concerns with internal temperatures inside a chassis, especially with tubed equipments? Or better to just use on the undercarriage?
So many factors, unknowns, and interactions -- it seems like only trial and error can produce satisfactory answers. The goal is to prevent vibrations at the resonant frequencies that most harm a piece of equipment's performance from affecting that piece, regardless of whether those vibrations are generated internally or externally, right? So, to start with, how many of us know what those harmful frequencies are with regard to most of our equipment? And then, choosing an overall isolation philosophy versus a distribution philosophy probably means choosing some tradeoff between goods and evils, which of course is normal with this hobby.

I use the word distribution instead of coupling because it strikes me as a more worthy opposite to the word isolation in terms of indicating what we're trying to accomplish. It indicates that we're trying, through coupling techniques, to make our piece of equipment become part of a larger system whose overall vibrational characteristics are more favorable in terms of the piece of equipment's performance. We might be trying to bind our piece of equipment to a shelf, a rack, the floor, or even to bedrock. (I'm in the camp of those who think "draining" is a misleading term.)

Mass-loading, which has been brought up almost as a third approach, falls into the distribution approach, both by changing the immediate characteristics of the piece of equipment's case and by increasing the effectiveness of the coupling between the piece of equipment and the shelf underneath and who knows what beyond.

Notice that coupling has to play a role no matter which of the approaches, isolation or distribution, we (think we) are taking. If we're using isolating footers, we have to make sure the footers make really good contact with the equipment. Luckily, this seems to be a built-in characteristic of most squishy footers. Let's say that for isolation we're putting a heavy sandbox or lightweight Neuance-type shelf under the equipment. Then we might want to choose footers for the piece of equipment that (we imagine to) have good coupling characteristics. Otherwise, we might not realize the benefit of all the trouble we've gone to to provide a special shelf for the equipment.

Of course, it's all a bunch of compromises anyway, and it may be that in the case of any particular piece of equipment, the designer has chosen a compromise solution that's as good as any we'll come up with. Sometimes it strikes me like trying in the stock market to beat an index fund, but actually, the odds are much better here, since we have some degree of control over our equipment and rooms.

Clearly, there is some good we may be able to do through our obsessions. That is, some solutions do reduce distortion that we are able to hear. After that, there is a whole bunch of sound tuning that we can do to indulge our infernal restlessness.

Anyway, various people have put forth some useful concepts about what vibration control approaches work best for particular parts of the system. In practice, since vibration is attacking from both land and air, as well as, I guess, from within, probably neither isolation or distribution is theoretically a perfect answer. But we can't execute either strategy perfectly, either, so it's all good! Random trial and error may be as effective a strategy as one of the more coherent conceptual approaches, but it probably doesn't make us feel as good about ourselves, which is probably another inherent goal of the hobby, eh?