Can I put receiver and CD player on top of my sub?

Sorry to be a Nay-sayer, but if you are going to put your gear on top your sub, then I would say putting zip-lock bags filled with sand is dangerous at best. This is in your bedroom, right? Well, what happens if you accidentally spill one of the bags on the top, or knock it over. I'm sure we'll all agree that vibrations won't kill your cd player, they'll just interfere with the sound. Sand, on the otherhand...get that in your gear and you'll be pretty unhappy.

Judy426-

Your sarcasm detector is not functioning.

No. Not recommended.
Ideally speaking, some serious referrence speakers have their crossovers mounted outside, on a separate box. Why would you want to shake the mounts and other components of a CDplayer and other gear on top of a subwoofer.

If space is a must, then, try an isolation trick as many suggested above. If there is a choice, avoid this set up.

I answer many questions so I dont need a lecture I was simply pointing out what I saw, P.S. I would not stack my gear on my sub....is that better?

Chadnliz thats perfect.