The PA System You know the feeling - you're standing in the middle of the crowd at a show and everything sounds awesome through the gigantic stacks of speakers at the sides of the stage. The bass drum feels like it's pounding directly in your chest. You can hear the sound of the guitar rising clearly over the drums. And despite the fact that it's all incredibly loud, you can still hear every word the vocalist is singing. How do they assemble all that gear on stage so that you hear everything clearly and at the right volume? It's called the Public Address system ("PA" for short). A PA system uses the following equipment to amplify and control the sound an audience hears during a live performance, as well as the sound that the musicians themselves hear on stage:
or no PA at all... If you're a musician thinking about getting the best possible sound during a rehearsal or live performance, there are two basic PA questions: Do you need your own system, and, if you do, What kind of system do you need? If you're a band of instrumentalists (no singers) rehearsing in a garage or playing at a house party, small club, or even a school auditorium, the musicians can probably control the sound just fine without a PA system. If you have singers, you will almost certainly need at least a basic PA no matter what size room you're playing. Once you've decided to go for a PA system, the next thing is to figure out how much system you need. Again, the type of music you play and the room where you will perform will provide the answers. Let's look at a few examples.
Cause and Effects... Notice that Example 3 also includes effects. If you follow the green signal path, you'll see that one cable comes out of the mixer and into the effects box and another cable goes out of the effects box, right back to the mixer. This is called an "effects loop." By turning the effect send or "Aux Send" knob on each channel of the mixer, the effects can then be adjusted individually for each instrument running through the PA. This means you could put a lot of echo on one singer while adjusting another singer to have almost none. It Just Gets Louder From Here... Hopefully we've been able to give you a basic idea of what a PA system is about without getting too technical. If you're concerned about missing some of the details, there's lots more information to be had by visiting www.shure.com.

PA Setup