Cornwall II's on an Auralex Great Gramma isolation platform?

[jimjimbo]

Good idea? Bad idea? How about spikes, or is sitting on the carpeted floor preferred?

[Sancho Panza]

Do yours have risers?

[Sancho Panza]

Looks like from the pic they do.

I'd try them with & then without & see what sounds best to you.

[EmilC]

Looking into these options myself.

I dont think the granite will accomplish what you're trying to do which is drain vibration away from the speaker cabinet.

I think you would still be better off with spikes or the Auralex.

You also may want to consider products from Herbie's Audio Labs especially the " Big Fat Gliders"

http://herbiesaudiolab.net/spkrfeet.htm

[garyrc]

After a lengthy discussion with an extremely knowledgeable person about these sorts of things....I now totally think it's a bad idea. And actually, I'm going to remove the risers as well and try it out. He suggested a nice piece of 1" granite cut to fit under each speaker, to not only be aesthetically pleasing, but providing a "rock solid" base for the cabinet. I'm sure there are alternatives, but I'm going to try and find some funky pieces of granite remnants and see what happens.

How squishy is the Auralex? You don't want the Cornwalls to be able to rock back and forth when the SPL gets high, AND you don't want a cavity beneath them. Directly on a wood or concrete floor (with a carpet in front of them) may be the best.

For wood floors, Stereo Review suggested putting a very sturdy beam on piers/pillars in the basement or crawl space, across the joists, pressing up against them, to keep the floor from springing up and down. We've done that in two houses in a row, and it seems to help ... but, on the other hand, this could be like praying, "May this house be safe from tigers," when leaving one's Manhattan apartment.

Spikes may be good for carpeted floors, and are good for the spike industry. Our Khorns seem to sound the same on carpet or off, but the carpet is not very thick, and, after sitting a few weeks it gets pressed thin by the weight of the Khorns.

Edited April 6, 2014 by Garyrc

[garyrc]

The Auralex is not squishy, pretty firm actually. But.....there is a cavity directly in the middle underneath, which is about 80 percent filled with an acoustic wedge. Easier for me to send a link that to try and describe and type all that stuff.....

a

http://www.auralex.com/sound_isolation_gramma/sound_isolation_gramma.asp

http://www.amazon.com/Auralex-GREAT-GRAMMA-30x19x2-75-Charcoal/dp/B000FDU2UK/ref=sr_1_1?ie=UTF8&qid=1396793919&sr=8-1&keywords=great+gramma

I ordered two beautiful pieces of granite remnants yesterday that didn't cost much at all, since they were sitting in a back warehouse probably forever. Having the edges polished, and will have them in about a week. Not that I'll be able to see much of them, but hey, at least I'll "know" they are there...will also post my impressions pre and post installation.

a < 2.75" (overall Ht of the Auralex) cavity might or might not hurt the lowest bass response. I think PWK may have been complaining about the still present habit of people putting speakers on legs or a pillar. The latter might help imaging (???), but hurt the lowest octave of bass.

I thnk the granite should work well, if it is smooth enough to provide good contact with the speakers and the floor.

Good luck. Please let us know how it turns out!

[Sancho Panza]

I would think on the Risers, in a Corner & on the floor is how they were designed to be run.

Wonder if Slant Risers, like the Heresy, have been made?

Maybe Bob Crites?

[garyrc]

I would think on the Risers, in a Corner & on the floor is how they were designed to be run.

Wonder if Slant Risers, like the Heresy, have been made?

Maybe Bob Crites?

Yes, even though the name "Cornwall" was meant to indicate that it would work well either in a corner or against a wall, PWK contended that ANY full range speaker would sound better in a corner. He probably had bass response in mind. He also said that moving a speaker from out in a room to deep into a corner, would be like multiplying your amplifier power by almost 4.

Edited April 7, 2014 by Garyrc