Granite Under Speakers Over A Wood Floor

I will not venture to say these work better or worse than a marble slab, but, you can get various kinds of floor protectors. These are available in a myriad of materials from lots of dealers. I use Tip-toes. The good news on these is that you can easily move the speakers to adjust toe-in, etc.

I'd recommend trying coins first. It should cost somewhere between $.06 and $2.00, depending on the coin and the amount of spikes. Although, I hear that old Spanish doubloons are eerily transparent and sublimely musical. :-)

Stones under speakers on a wood floor can improve the sound in many ways, but always bring some artifacts of the sound of the stone along to the party too. Therefore you need to choose the stone carefully. Granite is not good. Impure marble, soap stone and sand stone are all better. Even so you will still need to make sure the stone does not wobble on the floor - but upturned tip-toes work OK and the spike connects with the stone not the floor.

My system is also on a wood floor. I use 3/4x15x24 inchs slab of Granite under each spiked speaker. I work in construction and get it free. When a builder puts in granite counter tops in a kitchen the sink and built in range top are cut out and left as scrap! Check a few sites, talk to a few supers. For a six pack of beer and ten bucks the installers will trim and size the material while you wait.

I indeed have my Merlin VSM-Millennium over spikes over a granite slab (cut from a piece of my kitchen countertop where the sink goes) over wooden floor. I put four plastic "stickum" feet under each slab to isolate the slab from the floor. Works well in my opinion. I had expected the sound to be edgy (and the Merlin can sound like that in some setup) but it is not so. Very clean, detailed sound yet not fatiguing. By the way, since the kitchen counter has a shiny side, I put the rough side up to the spikes provide good coupling with the slab.