A sound mixer is used during a live performance to control the sound outputs of the various instruments or voices which need amplification in a room, auditorium or other venue. A sound check is used to test out the relative levels of all of these signals, though they may have to be turned up once the performance begins. A sound check should be done slowly and systematically and you should test each channel individually to optimize sound levels.
Set all of the faders on your mixer to "0" decibels. The faders are the movable slider located above each input channel on your mixing board.
Have someone test the instrument or microphone which coordinates to channel 1 on your mixer. There will be a gain, or volume, knob located at the top of each channel. Turn this to raise the volume of the channel to a level which fills the room. Remember, however, that when people begin to fill the room, they will absorb a lot of the sound. Therefore, it may be better to go higher with the gain knob than lower. Do not turn the knob so high that you distort the sound, however.
Repeat this process for all of the inputs on your mixer, checking each microphone or instrument to ensure that each one sound is relatively balanced. What this means is that each sound is loud enough to fill the room, but not loud enough to overcome other channels.
Add effects to the inputs if your mixer allows for it. Adding a slight echo or reverberation, or reverb, to a vocal track will make it sound nice and sometimes adding a little delay on drum tracks may come in handy.
Re-adjust the gain knobs on channels to which you applied the effects. A reverb effect, for instance, may make the sound fill the room a little bit more and so the gain knob can be turned down slightly.
Use the faders during or just before the performance to make small adjustments to the levels of your inputs. You should never move the fader more than 3 decibels in any direction at a time, and you won't have to if you set your gain knob properly at the beginning.
Tips & Warnings
- Have at least a few guys on the stage helping you with your sound check if you can
- When you set levels for drums, make sure to run through each drum channel individually before mixing them all together
- Make sure that cables and wires are firmly attached. If you are not getting a signal, this may be the problem.
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