I prefer topless:
In fact, I even took the metal cover off my breaker box because my system sounds more dynamic (less constricted). I replaced the cover once, but didn't like the resulting affect on my system, so I removed it again and have been enjoying it without the cover for the past few years. (Kids don't try this at home!)
I also had good results removing the top covers from some tube preamps and amps. I just cover the gear with plastic when not in use to keep the dust out. --Bruce
In fact, I even took the metal cover off my breaker box because my system sounds more dynamic (less constricted). I replaced the cover once, but didn't like the resulting affect on my system, so I removed it again and have been enjoying it without the cover for the past few years. (Kids don't try this at home!)
I also had good results removing the top covers from some tube preamps and amps. I just cover the gear with plastic when not in use to keep the dust out. --Bruce