What isolation feet under your amp with great result?

What about those cork squares in a lined rubber sandwich design? I have them under my Plinius pre and amp. Inch and a half thick, 2.5" square. Put them under the component, not the feet. They seem to provide isolation and detail. They were the rage coupla years ago. Anyone comment on their experience with these? Not much dosh ($). 

@lowrider57  I tried Myrtle wood blocks and there was a major improvement over Herbies, faster attack, open soundstage, but the highs became harsh. Looking for an inexpensive tweak. 

Before spending more money, try putting a thin piece of sued leather, just slightly larger than the block, between the bottom of the Myrtle wood blocks and your component. It will not hinder the performance of the blocks but will eliminate any micro vibrations that can build between the component and the coupler, which sometimes shows up as a sibilance in the highs.

It's a cheep experiment, I think will solve your problem without negating your otherwise good results.....Jim

@camb - interesting that he isolated the speakers first.
I have also put all of my system items on springs, even power supply you can see in my system page. Funny as he said to use the same method throughout, which I also have done.
However the stand mount speakers are on wave springs, which are not optimal, and yet it still makes a considerable difference regardless.

I will be using a damped mass device on top of electronics like the ETI AMG topper, as well as on my speakers including subs as I add more of them.

I am currently building an isolation rack to work in unison with the AMG toppers on electronics. Same idea, to absorb vibration from the components, just implemented differently.

camb - thanks, informative.

https://systems.audiogon.com/systems/8721

@jhills  +1 for the spikes into maple platform.
Between the maple and shelf I use a gel type material which gives me a floating platform.

Re: wood blocks. I used a ayer of cork under the Myrtle blocks. I still had the tight bass and open soundstage, but highs remained harsh. I think the vibration of the component passes to the wood, then back to the component chassis.