REL Strata III spikes

Mine had spikes and I found they improve on hardwoods

Forget the spikes and forget the rubber feet. You may get better sound with your Strata III by doing what I did.

Turn it upside down and put a board on the now upturned rubber feet, with something weighty on top of that board. You may have to turn up the volume level a bit on the sub, but the bass should get tighter and more tuneful. I also found, contrary to common "wisdom", to keep it out of the corner.

Enjoy,
Bob

Talked with Sumiko awhile ago. Recommended not to use the spikes unless on hard wood floor and not on slab foundation.

It depends who you talk to at Sumiko, I was given contradictory advice in emails by two people there about whether to use rugs under the subs. I used mine on concrete [with rugs] with the cones and they worked fine. Of course I don't know what the stock spikes are like; I have found that the brass cones are much better than the stock steel spikes supplied with speaker stands; you would expect this as they cost much more and are obviously of higher quality.

I was thinking I would go to a hardware store and buy bolts with the proper thread size and use a grinder to form a point. I would then use Isoclean support discs under them to both protect the floor and give isolation.