Energy damping or energy transfer?


Are there some generally accepted guidelines about which components to isolate (in terms of vibration damping) and which components to "couple" to the rack (which is also coupled to the floor)?

I freely admit to being clueless here (I'm still trying to get my head around cables and power cords), but it seems like the "brass spikes" guys are saying something completely different from the Vibrapod-type isolation guys.

Given what they're asking for these products and the potential number of components involved, it's like considering a major component upgrade.

Also, has anyone noticed once a component is isolated/coupled that either the interconnect or power cord is affected? Thanks. If this has been kicked to death in the past, just posting a link would be great.
lrdmax
Thanks for the replies. Looks like 2 to 1 in favor of isolation for components.

Among other applications, I'm working on a custom equipment rack that uses an angle iron frame with hardwood shelves. I wasn't sure if I should try to couple the shelves to the frame (by epoxying some type of small points to the shelves and having the points contact the frame) or isolate the shelves from the frame.
For isolation, I was thinking about a combination of cork and sorbothane.

Then there's the issue of isolating/coupling the components and the shelves, or, like Bojack says, DO NOTHING. ;-)
Before you take the approach that 2 out of 3 people are in favor of isolation, it might be in your best interest to try bother ways and see for yourself.

I found that too much isolation or damping had the tendency to dull the sound, where coupling brightens it. You'd be doing yourself a great disservice if you don't experiment.

An audiophile will always experiment trying to get the best sound in their system. Taking the majorities opinion and running with it blindly, especially when only three people have responded, may or may not be right for your system.
Krell man's chemist friend is correct when he said, "nothing can stop airborne vibrations".

That's why you need to expedite the transfer of resonant energy away from the component.

Of course if you'd like to trap those vibrations (captured in a moment-in-time but can only dissapate over a period of time)inside your component you can always put some kitty litter or sorbithane material underneath the component.

-IMO
I've been thinking about this topic some lately. It seems to me that the ideal system would be a combination of isolation and coupling. Depending on where you live, floor- & structure-borne vibration can really kill your hi-fi's low-level resolution, especially for vinyl playback. That's where isolation comes in--air suspensions, sandboxes, squishy feet, etc.--to keep the floor & structure-borne vibes from getting to your component. On the other hand, component-generated and airborne vibration are also destructive to low-level info. In theory, coupling seems to be the solution here, whether it's to a support that dissipates vibrations quickly (constrained layer platforms, some solid wood platforms) or to a support that resists movement in the first place (heavy stone slabs and the like). So my theoretical ideal would be to couple the component to a vibration 'sink', and then to isolate that system via some kind of suspension. This ignores energy storage in suspensions or coupled platforms, and probably other issues I'm unaware of.

This idea is based in part on personal experience. I live near a busy intersection. By far the best thing I've put under my turntable--an unsuspended Rega P3--is a DIY, inner-tube-based air platform. The improvement is not subtle. My theoretical explanation is that the air suspension is isolating my TT from traffic-generated vibrations. Second part of my idea is based on my experience that my 'table sounds better if it has hard feet between it and the suspended platform (made of mdf). The setup is pretty crude, but it will remain in my system until I buy or make something prettier that does the same thing.

I've also put my tube amp on a similar air-suspended platform, but I don't hear any obvious differences with it. With speakers, common sense tells me that the speaker cone's mass is too small a fraction of the cabinet's mass for it to make a difference, but damned if I don't like my stand-mounted speakers better on spikes than on blu-tak. This could have to do with cabinet resonances rather than movement of the cabinet relative to the speaker cone though.

Brent
Krell man, you're right. My "statistical summary" was kind of tongue in cheek; sometimes kind of hard to get that across in print. Given the frequency with which this topic is apparently covered around here, I guess I didn't really expect a lot of posts, hence my summary.

I would like to try both approaches in developing my rack. Without going to the expense of buying lots of brass cones, any suggestions for testing out the coupling idea? Thanks.