I have been to numerous concerts and have seen the drum kit surrounded by plexi-glass. At a recent Rod Stewart concert the glass went over the top of the kit. What is the reason for this? How do drummers feel about this and is it uncomfortable?
Hi, Mike-- Plexiglass does not absorb sound--it just REFLECTS sound. It is used in as a drum shield in a number of ways. Sometimes it is used to contain the sound of the drums so that it reaches the audience as reflected sound instead of direct sound. This application is mostly to make the drums less loud in small venue.
In a concert situation, the shield around the drums is used to reflect the sound back to the drummer without allowing it to travel straight into the microphones used by the vocalists as well as any other microphones that may be in the path of the drums. The high volumes of the vocal and other mics combined with the drum mics can cause serious problems with feedback.
When you saw the entire set covered it is most likely an application which allows the cymbal mics to be isolated in much the same way.
Is it uncomfortable for the drummer? No, I think that it is much MORE comfortable because it allows the drummer to hear his(her) own sound to be naturally as the drummer would hear it without the sound being dispersed into such a large venue.