Isolation of stacked components


Hi. I have two stand alone SS subwoofer amp/crossover units that provide power and integration of my subs wih the main speakers. These units each weigh about 35 lbs and have a foot print of 12" deep, 3" tall and 20" wide.

Currently, due to shelf space limitations, I have these two units stacked one on top of the other on the bottom shelf of one of my two Billy Bags equipment racks.

Can anyone provide a little guidance re: isloating the units both from each other and from vibrations, etc.

I use Herbie's Audio Lab products to great satisfaction for most of my other equipment. Before I went back to HAL, I wanted to get opinions/some thoughts on a starting point. Questions I have:

* Is there any value at all with isoalting sub amp/crossovers?
* Should I consider a "shelf" between the two units, such as CF shelves from BDR or Oyaide?
* For feet, is this a brass cone/CF cone application(BDR, Walker points, etc) or a poly chemical application, like HALs?

Any advice to start (including don't waste your money) is appreciated.
128x128flyfish2002
I have done some research on this topic and learned alot. I am getting ready to try a solutions.

Question: has anyone actually shielded the power transformer of stacked components to reduce EMI/RFI? I have found fairly easy and inexpensive solutions that involve creating a "cap" of shielding material to cover the power transformers. I do wonder if anyone can comment re: air flow and heat build-up inside the units when the power transformer has this "cap" in place.
Thanks for the responses. Steve at HAL did suggest I try four ExtraFirm Tenderfeet under the bottom unit and four regular TenderFeet between the two units to ensure proper loading. I have had ALOT of luck with his advice and products, plus they fit in my budget. I think I will try this approach.

Any specific suggestions re: either shielding the transformers themselves or a shelf that will provide some shielding?
I am in the same position as a have to stack some equipment.
The best you can do is to use Still Points "Comonent Shelf" with 3 or 4 legs. Non inexpensive but worth every penny

All The Best
Rafael
Transformer Flux leakage and Vibrations migrating from the upper component to the lower component are probably your two worst enemies

Depending on the type of transformers used in the components will determine how much and how critical the Flux field will be

EI type (square box type) tyrannies tend to leak in all directions were as Torrid's (round donut style) tend to leak in a much more limited / narrower range

You can try shielding the transformer itself or use a platform with some type of shielding between the components

Note that in both cases you are dealing with lower level EM leakage ( vs higher level RF type noise ) and will require some type of permeable shielding like copper to absorb and dissipate the EM Flux field

As far as vibration control you wouldn't want to direct couple the upper component to the lower component as this would allow vibration from the upper component to migrate to the lower component ... possibly compounding the problem

You want to Isolate or decouple the upper component from the lower component so vibes are blocked from entering the lower component

When decoupling you must properly load the decoupling device according to the component to be isolated weight for it to work effectively

All decoupling devices have a resonate frequency point ... above this point the decoupling device will work properly ... below the res/freq/point of the decoupling device ... it can't handle the magnitude of the vibration and over loads locking up and will actually work the opposite and couple the component instead of decoupling it ...

Talk to Steve at Herbies about proper weight loading of decoupler for maximum effect
Any equipment I have stacked I put hockey pucks in between. They are cheap enough and some times I double up (2 in each corner instead of 1). It's worth a shot and will not break the bank.
If you components are 'open' to the room, the acoustic energy will provide vibrations that will impact the sound you hear. Best to put everything in another room, then you get 'pure' sound. I am sure you have seen high end media rooms wherein all the stuff is out of 'sight' and therefore sound. That is the way to go.