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
Rakuennow -In my experience, cones "drain" in one direction. Try putting "spikes" or cones upside down under a Turntable as I described above if you doubt it. My guess is that ball bearings isolate better as opposed to "draining". If the cones drain the vibration into a platform, chances are the materials will absorb at least some of the vibration. It would take a carefully engineered rack to transmit all that vibration to other shelves. Also, I believe most people will respect the weight limits of the rack they choose to use.
Thanks for the reminder that viscoelastic materials turn mechanical energy into heat. Good to know.
In audio, one of the sources of vibration is the very thing you are generating- the sound. This poses problems that are unique in application.
Even if you doubt the significance of vibration control for most components, you must see the benefits for analog equipment.
CD players are also mechanical devices as they depend on reading a moving disc so vibration will have an effect on them. Note the effort by some of the top players to deal with vibration by floating the components on the chassis. I have my TT and CD on roller bearings and the rest on the Star Sound cones. The thing to bear in mind is that ALL of these things "work", i.e. change the sound. Which is best varies from system to system and owner to owner. And from time to time, I have changed my mind about which I prefer more than once.
Stanwall, I think you hit the nail on the head when you say 'works' means changing the sound. Good point!

I notice one fella sez he likes his phono cartridges when they are not torqued too on the headshell very tightly. Obviously he likes the sound of a little bit of added resonance. Some folks seem to like tubes that are slightly micro phonic which will also convey some extra noise.

So IMHO, it is not so much about what eliminates the effect of resonances in your systems but how you can alter the resonances and tune your system to get your preferred sonics.

Works for me.
The results (positive or negative) from using ANY form of vibration control on an ANY component will vary according to the particular design of the model, system synergy/tuning and personal taste. The only way to determine what will work depends on experimentation. At a dealership, I heard the use of such devices under various CD players and there was no single product that was consistently helpful under all models. For example, the Symposium Ultra shelf (vibration drain) is incredibly effective at what it is designed to do. Use under some CD players resulted in greater clarity, detail and more obvious microdynamic contrast. But, under an Aero Capitole player, the sound became WAY too dry and lean. Under my own player (Naim CD555) the platform had very little effect. I've also done some experimenting with footers and Symposium rollerballs, etc. and I also find the same thing--sometimes the result is good, sometimes not. I don't think there is any kind of consistent "right" approach.

The same is true with all other components. While the most common approach with speaker is to couple the speaker/stand to the floor with spikes, I often find alternative, decoupled approach, works better on suspended, wooden floors. My speakers sit on Symposium Ultra shelves which have a soft inner core that drains/absorbs vibration from the speaker. I am just guessing, but, this probably keeps the floor itself from acting like a sounding board. Again, only experimentation will give a meaningful answer.
Newbee, I believe it is all engineering and physics. Everything affecting the sound of our systems can be evaluated and modeled using engineering laws, mechanics of materials, and psychoacoustics. What's left is psychology and personal preference. There are variables in that every designer has their own take on how the engineering affects the sound, which factors are most important when trying to achieve sonic excellence at a price point, and trying to guess at the personal preferences of their customers. Our personal preference can be affected both by the sonic traits we each associate with enjoyment, and also by other factors such as appearance and perceived value. It gets more interesting when we audiophiles are Jedi mind tricked by manufacturers who use science for profit by explaining just enough of something to make us think their product uses "new technology that is better than anything before" or by appealing to our visual perceptions by offering things like thicker cables that must be better than thinner ones, or new age materials like carbon fiber on our outlet covers. I suspect we also spend quite a bit of money for things that may make a positive difference that can be explained scientifically, but perhaps not a sonically significant difference. With regards to vibrations, I cannot argue with the practice of trying a bunch of stuff and using what you like best. Just because it isn't scientific doesn't mean it can't be fun.