If your walls don't vibrate much, a wall shelf is the only thing recommended here that will work. Batters, like pole magnets, and springs all are the same and like hard and soft feet have resonant frequencies which may or may not help.
Turntable isolation
I have my TT (Rega P7) on top of my audio cabinet. The cabinet is an Ethan Allen Townhouse component cabinet with a marble top. I noticed this weekend that when I touch the doors to my audio equipment I can hear a light thump via the cartridge. Even when I lightly tap the door the sound travels through the cabinet woodwork, through the marble to the cartridge. How can I isolate the TT from the rest of the cabinet?