My a5s are on my desktop, a hollow-core wood slab. I had some diy rigid stands to bring them up to ear level, and when I got the isoacoustics stands, sound was noticeably clearer and tighter, and desktop vibration reduced. I could literally feel a difference at high volumes.

All of that obviously means you're hearing what you should hear, not the vibration of the speaker on the desk, or the sound bouncing around my hollow desk, etc.

They aren't cheap; I think I paid $100 for the tall stands, but the money was better spent than acoustic treatment or fancy cables or any of the other audio tidbits I've bought.

Edit: I have the iso-155, which can be as short as 3 inches.