Anybody own a component that sounds better with the cover off?

One of my early vibration control lessons, dealer told me people like their Aronov amp better with the cover off. Sure enough, no doubt. 

This is almost certainly due to the elimination of cabinet ringing. These things all vibrate, that is why they sound better on springs. And they all ring, that is why they sound better with damped springs like Pods. Cabinets are a trade-off between sound quality, dust, and safety.

or just remove the cover (cost = $0).  And avoid buying springs and pods.

I leave my toilet lid off,and it works much better.

I owned an Audio Research SP-8 years ago that definitely sounded better with the top panel off. Probably could have stayed on if the right kind of damping material had been used.

This was first mentioned decades ago in The Absolute Sound, by Enid(?).  This might be why ARC has moved to plexiglass tops on their line stages.