I work in live events (I actually did a Rick Astley gig in Manchester last Friday) and can tell you that they're to deflect flying bottles of piss, as the drummer can't easily swerve them.
(Not really...they're to cut down the amount of sound coming directly from the drum kit to the audience, so the levels can more easily be controlled via the PA, usually in smaller venues.)
(
Happosai _,,,,_(O ; o)_,,,, Thu 6 Apr 2017, 9:13,
Reply)
They're to prevent flaming bits of wood from spitting out
missing the hearth, and setting your living room rug on fire.
(, Thu 6 Apr 2017, 11:52, Reply)
I work in the factory that makes these. It's actually a changing room for exhibitionists.
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Flash_Bastard, Sun 9 Apr 2017, 0:09,
Reply)
Sound guards are a godsend
If you play in a group with the trumpets behind you. Proper deafeners when they want to be.
We use those sound barriers for isolating drums while recording alright, prevents spilling into other mics while playing as a group.
There are circular clip on sound barriers for brass players to put onto their microphones.
The sound that doesn't go into the mic bounces back to you so you can hear yourself even if the sound engineer doesn't put the right amount into your monitor. Really handy stuff
(, Tue 11 Apr 2017, 1:34, Reply)