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Help needed for isolation under the power amps

I need to circle back to putting the proper isolation and mass loading under my Conrad Johnson LP140 mono blocks as circumstances led to a poor resonance impasse: 

My active components (cfr my systems page) has space limitation due to the fact that they reside on two levels in the designated space of only 40"w x 28"h x 32"d within the custom made cherry cabinet that was designed for my AV needs in the mid 90s. On top of that, the cabinet has to be placed directly against the wall, which makes any change to the active components cumbersome. 

The cabinet stays (a compromise with my better half) so I can not have an audio rack where the energy drains properly to the (wooden) floor and unfortunately the European cherry of the cabinet resonates more than I would like. The "A/V equipment space" limits the use of more solid material underneath the amp (again, please see my systems page. Also note that I have Symposium Svelte shelves under the mono blocks which are not depicted as at that time when the pictures were taken as I trying them out under my other set of speakers).

Any suggestions, especially for under the mono blocks? I am going to raise the shelf a bit where the source components sits in order to put mass loading material under them. I can go as far as 4" in height.

So the question begs? Which material would you suggest? Under each amp, I could use e.g. a double stack of 16"x16"x2" pavestone, a duo of 18x12x3" granite surface plate machinist tool, may be custom cut marble slabs.   
Besides mass loading under the amps, I am thinking of adding some metal brackets between the cabinet and the back wall to offload energy as my wooden floor is a bit lively.

As for feet under the mono blocks I am currently using the BDR cones and pucks, hoping to change the frequency of the interacting resonance of the cherry wood. Am thinking to replace them with ebony footers once I have the proper mass load. Also here I solicit your suggestions for the footers.


128x128jazzonthehudson
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jazzonthehudson's avatar
jazzonthehudson OP
277 posts
 
/bdp24: As mentioned before, I am not sure about ml as Peter of Symposium hinted it may or it may not work. Before I trend to no ml, which is of course easier for me to execute, i.e. doing nothing.
So again, I am not asking for ml but I did ask for input and got your opinion, thanks!

Minus K is indeed not an option (did you try that out yourself?). I would rather jump on the more popular SRA boat before. Besides the fact that one CJ LP140 is too heavy for the Townshend Seismic Sink, it is meant for TT where isolation is key, not transfer of energy which is more important for power amps. 

Barring an eureka moment, I will likely circle back to Symposium and add Svelte Super Plus shelves under the mono blocks and try an additional layer (probably Dupont Corian) under the upstream devices.
bdp24's avatar
bdp24
9,821 posts
 
Not yet on the Minus K, jazz, though I really want one for my table. At around $2500, it'll have to wait.
cerrot's avatar
cerrot
1,700 posts
 
I LOVE Syposium. I did get some pretty incredible results with SRA, as well as still points.  Me - I'd get a divorce, have her take the resonating cabinet with her and buy yourself a nice rack that does what it is supposed to do for your components.  Married life is overated.  Can't hold a candle to good music. If you ever find your self missing her, just play some Julie London.  Once you hear her voice w/o that cabinet resonating, you will forget everythig ;-)
jazzonthehudson's avatar
jazzonthehudson OP
277 posts
 
/cerrot: I wouldn’t gamble on the divorce as mostly one ends up with a trauma dealing with the lawyers and a residue of one's fortune, financial and emotion wise, that is in a worse case of matrimony. I count my blessings, my better half is indeed the better half. 
BTW you have nice systems! I haven’t tried Finite Elements yet.

Speaking with Peter yielded better understanding of isolation and the application of his indeed affordable products. He was very helpful!
I ordered some Svelte Plus under the amps and Segues for the upstream gear in my second system.  Thanks polk for the tip on B ware units!

A slab of 1 1/2 " granite is underway as well, just in case. I tried ml under the amp in the library as it also sits in a cabinet and it did change for the  better.
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