[arsun]

I am currently focused on a DIY project which is an open bottom tube amp. I only have the corners for isolation. I am thinking the following: How about getting 4 soft tenderfoot at each corner and then placing the amp on a granite slab. However I also want something to go between granite and the shelf itself, what is recommended here? I think 3 iso-cups will be kind of overkill, but I am open to suggestions . I am thinking of extra  thick grungebuster Dots. Will it be good enough? Should I go for iso-cups?

[max190]

arsun,
I don't understand the need to add the granite slab on your shelf.  Is it for looks?
I would think 4 Iso-Cups w Lampblack balls and then add Herbie's tube dampers to all your tubes would give you excellent results.

[arsun]

Steve,

The problem is that the amp does not have a bottom and all the interior parts are in open. The slab is not only for looks but also for covering the bottom. The amp will serve the purpose of a headphone amp mostly and it is not too big, so it can be carried around. The iso-cups under the amp (between the slab and the amp) are out of question because of their size and shape. The corners must be rectangular and must have the dimensions not bigger than those of tenderfeet. I hope that clarifies things a bit. I will order tube dampers as well, but I haven't decided on the best isolation approach considering my constraints. The only way I can use the iso-cups are if I place them under the granite slab. Another question then, is it better not to use tenderfeet and covering the bottom completely with the slab and using just 3 iso-cups under the granite? Or maybe some other material between the amp and the slab and again 3 iso-cups under it?

[max190]

arsun,

I see what you mean about the Iso-Cups not working under the amp.
I think it would be better to use the Tenderfeet under the amp and then Iso-Cups under the granite.

Hopefully Herbie will check in here soon and give you his insight.

Good luck,

[Herbie]

I think the best solution is to use Tenderfeet between amp and granite slab and grungebuster Dots between slab and shelf. Four 1" standard-thickness (1.6mm) Dots would be sufficient in most cases. Extra-Thick Dots would not be overkill, though.
 
You don't need to build a woggly totem pole to set your amp on. A tight, low profile between the slab and shelf is usually best. All you need is a decoupling interface between slab and shelf and grungebuster Dots provide this superbly. We have lots and lots of customers using this configuration between maple and granite platforms and shelf; it's a tried and proven solution.
 
Steve
Herbie's Audio Lab

[arsun]

Thank you very much for the information. 4 Tenderfeet and 4 grungebuster Dots will be great then. I appreciate the help.

[rollo]

you might consider Spruce in lieu of granite. Check out the mother of Tone site. A combo of Herbies products and Spruce may just float your boat. Worth a look.


charles

[arsun]

Thank you for the reply. I will check that Charles.

BTW, I saw under misc items on Herbie's site that there are tenderfeet with some cosmetic flaw. Will they work worse compared to the regular ones under some medium heavy load? The reason I am asking is that maybe I can replace the grungebuster dots with these tenderfeet, since they are close in price. So, at the end there will be 4 regular and 4 irregular tenderfeet for the application. If they perform the same, maybe I order even 8 of them to save some more money. What do you think? 

[Herbie]

Hi again, Arsun. Tenderfoot Production Seconds work exactly the same as regular-production Tenderfeet. However, I recommend using grungebuster Dots (or extra-thick grungebuster Dots) between platform and shelf.
 
Steve
Herbie's Audio Lab