cones or amp stand-???

Either would more than suffice. But if you use an amp stand, I'd highly recommend using AudioPoints under it.

-IMO

I don't know whether you have tube amps or SS but I can think of no real benefit of coupling any amp to a concrete floor, nor do I see any downside from doing so. BUT, I would get the amp off the carpet to increase air circulation, using any kind of cones or stand. Could be a good Saturday project in your work shop if you are so inclined. You need not spend a lot of bucks on this unless you are just doing it for appearances. IMHO.

Newbie, the benefit of coupling the amp to the concrete floor using AudioPoints, or an amp stand with audiopoints under the stand and under the amp is to minimize the affects of vibrations and resonance on the components and ultimately on the sonics.

By coupling the amp directly or indirectly to the concrete floor, he is essentially creating a mechanical conduit for internally generated resonace and externally captured vibrations have an expedited exit path draining the the resonance energy away from the component and rack before it has time to accumulate and wreak havoc on the sonics.

This coupling methodology is quite simple and when executed completely with all components, rack, and speakers will produce an incredible increase in performance. In fact, the gains are in my experience equal to or better than a serious component upgrade.

Personally I've never had the pleasure of coupling to a concrete floor. Only hardwood and wood subflooring systems. But those I've worked with who know far more than I tell me that concrete is the best flooring system for coupling.

-IMO