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Isolation Recommendations: To Couple and Decouple?

I’ve built an audio stand with a rather heavy (150 pounds) rigid base, and shelves that rest upon, but are not attached, to the support structures beneath them. (Pictures of the unfinished stand should be up on my system page shortly.) 

What is the best method for eliminating resonances in each shelf? 

My instincts tell me that spikes should be installed underneath the rigid base to couple that portion of the stand to the concrete floor beneath the carpet, but that I should be installing decoupling devices between each shelf and the associated support structure it rests upon. For the time being I’m foregoing using devices under each component, subject to greater attention later. 

In the past I’ve used inexpensive Vibrapods underneath individual components but with only some small measure of success. But whatever benefit they provide to each component, they will not sit on the support structure beneath the shelves properly as their base is too wide. I need something no wider than 1.5 inches, and my plan is to use four of them per shelf, one on each corner. 


Is Sorbothane the best material for dampening purposes in this application? Are spikes beneath the base, poking through the carpet and sitting on the concrete floor the proper method? 

For any of you who’ve already tried this, I’ve considered attaching USB-connected accelerometers to each shelf for the purpose of measuring and then “tuning” the vibration isolation system, whatever it may end up being, once it has its component resting on it. Has anyone gone to the trouble of measuring and then eliminating sympathetic vibrations in this manner? If so, is it worth the effort? 

Any experienced advice would be most welcome! 
sixfour3
oldhvymec
5,101 posts
 
You are a vinyl person? That makes a difference. Vinyl can benefit greatly, more so than a CD source.  The more you isolate the better it is to a point.  Don't let the OCD get to kikkin' in to much.

Solid floors are great just make sure all points are close in standing weight. Equal weight distribution.

It would be cool to get some data on the accelerometers though,,

To couple or to de couple, on concrete floors.
Bass distribution I like raised up to the wall height centerline, works better
8 -10 foot lids or vaulted I think would be the best. My dream setup vaulted ceilings and 16-20 x 25-35. I'm close, just no vaulted, lids

I know on stem walls (raised wooden floors) DECOUPLE,, simple., 

I like outside Ampa style too. Nothing behind you the listener, just the gear.

Regards
mijostyn's avatar
mijostyn
8,570 posts
 
Couple the basic structure to the floor then float the shelves on something like Stillpoints. Use glass or granite for the shelves. Check out Grand Prix Audio. They do it right. 
millercarbon's avatar
millercarbon
12,531 posts
 
Paging rixthetrick
sixfour3 OP
21 posts
 
@mijostyn StillPoints are unfortunately outside the budget. Are there any other (cheaper) decoupling devices you’ve had good experiences with? Say, in the sub-$50/device category? 
I’m intrigued by the notion of using granite and will give that some serious consideration. Currently the shelves in place are soon-to-be veneered MDF, chosen because it’s relatively inert, cheap and easy to customize. Glass is out, however. I built a previous rack with thick tempered glass shelves, but they had a terrible ring to them that I couldn’t get rid of. On the other hand, I suppose acrylic might eschew the ringing problem. 
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