Stone/granite slabs for summits on wooden floors

[bonzo]

Hi, I need to put something to stop firing into the basement through wooden floors. Guy below is quite ok when I put my current sub on top of something, like a chair or an auralex pad rather than the the floor itself where he goes mental

Shall I add granite/stone slabs? And a small rug below the slab to pull it around? I can't damage the floor.

what stabilisers, do I put summits on spikes, and anything below the slab?

 

[bonzo]

Well, Rich gave a similar answer on another thread " The summits have a downward firing woofer, and if whatever is below them (hardwood or even those granite slabs you mention) is not well-braced, heavy, and/or rock solid, you could get vibrational resonances that will deteriorate your sound. ". But I don't have a choice, I need to add something down. The floor seems ok.

 

[bonzo]

What kind of spikes? Do I need something on the granite, something soft, to dampen the sound?

 

[roberto]

Hola Bonzo. If you take a look of the feet of your Summits, the spike is there. Put your Summit lay down on its side, and unscrew one foot. You will find the spike at the center of the foot. It is a great idea to have spikes under wood floor. Granite is a clever idea. The Summit manual explains this: https://www.martinlogan.com/pdf/manuals/manual_summit.pdf On page 14, you will find how the feet are built. Please tell us, how your new Summits sound is coming along. Happy listening.

 

[bonzo]

Just to clarify, speaker is positioned on the granite slab with the spike. The slab is on the floor? I wouldl also like to put a small cloth under the granite so I can move out holding the cloth rather than damaging the floor.

Maybe try an experiment with speaker on spike directly on granite, and then putting something soft between speaker and granite to dampen sound

 

[InterMechanico]

Here's a link to a previous discussion on this topic, outlining my (and others') success with granite slabs
http://www.martinloganowners.com/forum/showthread.php?14437-Hello-from-the-Uk

 

[bonzo]

Hi IM, in that discussion you say that the granite slabs should be 2 - 3 times the weight of the speakers. The Summits are 34kg (75lbs). So 100 kg slabs? How are you going to move it around if you want to adjust it

 

[Bevensee]

Have you considered slate instead of granite? It's much more inert. I am contemplating this myself for my Vantages since they make my floor sing along.

 

[InterMechanico]

Hi IM, in that discussion you say that the granite slabs should be 2 - 3 times the weight of the speakers. The Summits are 34kg (75lbs). So 100 kg slabs? How are you going to move it around if you want to adjust it

Ok, so I'll admit that in my posted link, I sound pretty Matter of Fact. I'm not a physicist though. I tried paving stones to tighten up the sound being produced by my Vistas. This was on carpet at my previous residence. It worked really well, so I purchased (2) three inch thick granite surface plates (used by machinists to verify the accuracy of precision measuring tools) to place under my speakers because:

a) they are more dense than concrete
b) they are more aesthetically pleasing than concrete

I have since moved to the top floor of a condominium, with laminate floors. Noise travelling through the floor is a potential issue, so I placed them under my speakers to reduce the amount of noise transfer into the floor, and my neighbours`ceiling. It worked perfectly. I mentioned that the slabs should be so and so heavier than the loudspeaker, but upon re-reading the post, it looks like non-sense.lol. However, look at it this way: The heavier the base under the speaker, the more stable it will be. Also, I think that it is logical to think that if something under your speaker (floor, block of whatever) can be made to transfer sound to somewhere else, you are wasting that energy being transferred to (somewhere else). In a butshell, the heavier the base, the more difficult it will be for your speaker to move it (the base), and the less energy wasted moving it (the base, floor, etc...)

 

[InterMechanico]

Wait! Summits have a downward firing woofer, which may create a weird sound reflection thing. Choose your base material very carefully. You could try UHMW (Ultra High Molecular Weight). It`s a plastic that is very dense, and probably reflects sound waves poorly, which may be desirable for your application.

 

[Ps68]

Bonzo, be careful with this.

It is a big problem for many people, myself included. I worked on a design of an isolation plinth, which works well, there is good separation of the bass cabinet and the floor. Another option, one that I did consider and respect, is Max Townshend's speaker bases (http://www.townshendaudio.com/hi-fi-home-cinema-equipment-vibration-isolation/) DO not be put of by the movement, these things really work well, I have first hand experience with the difference they make in terms of isolation and sonic upgrade. Your neighbour will be your friend..

 

[bonzo]

Hi how much do these cost, do you know?

 

[Ps68]

Around 1K a pair.

 

[bonzo]

Wow too expensive. Granite slabs can be less than 200 a pair.

 

[InterMechanico]

Wow too expensive. Granite slabs can be less than 200 a pair.

My slabs are 12" x 18" x 3" and cost me 75.00 each (CAD)

 

[bonzo]

I am seeing good value granite and marble slabs made for speakers. Has anyone heard on marble before, how is it different compared to granite?