I place mine under the chasis. Placement is determined by balance and sound. Generally, I find that one placed under or near the power transformer and, if a cd player, under the drive motor improves sonics. Balance is usually influenced by cable dressing. Probably the biggest factor in placement is balance---finding the placement where the component will rock or sway freely for an extended period after being put into motion with a gentle push or tap. Also I use various combinations of Herbie's feet and Big Fat Dots on top or underneath the Aurios for greater isolation and improved sound. Don't be in a rush when you install the Aurios. It takes patience and more patience to find the sweet spot(s) and the right combination of isolation pads or, if you use them, bearings (I like what Herbie's feet do vs the bearings). However, I think the payoff is worth the effort.
Where to place Aurios?
Under feet of my Rega P5 or directly under chasis? Same question for cd player, amp, pre amp etc...under bookshelf speakers?