If you’ve taught any music in public school, you know that running a sound board is expected of you even if you have no idea how to run one. It isn’t taught in our music education degree, and there are usually no courses that help us understand it. This means that we are usually left to spend thousands on a sound guy for a concert or figure it out on our own which can be a daunting task. I did a Workshop recently on the basics of sound with regard to live and from-source sound.
Setting Up Your First Sound System: The Music Teacher Edition
BASICS
The following equipment is a list of basic requirements for live sound:
What your school will likely already have:
Mixer
2 ‘main’ speakers
Vocal microphones
Enough XLR and speaker cables for each
You can get by with the above equipment but to make your equipment more versatile and accommodate many live situations your school will need:
2 monitors
Instrument microphones
Condenser microphones
Wireless Headset microphones
DI (Direct Input) boxes
Cable snake
Various XLR and 1/4″ adapters
2 Most Common PA Setups
Powered mixer with unpowered speakers
Unpowered mixer with powered speakers
The power has to come from somewhere. Plugging them in does not assume they have power. They need a built in power amplifier to generate power. Powered mixers will be heavy and bulky and will have cooling vents and a wattage value on the back.
Powered speakers will have a switch to turn them on and off as well as a levels and volume knob.
Pros and Cons of each system
Powered mixer with unpowered speakers
Can plug in anywhere and only needs 1 outlet.
Need to know a lot about wattage and impedance
Unpowered mixer with powered speakers
Need a lot of power cables and extension cords using multiple outlets.
Can easily mix and match speakers to customize setup without worrying about impedances.
Setup
Below is a typical setup for live sound taken directly from Chapter 3 of Rock Coach and also a version is included in a chapter from Technology for Unleashing Creativity:
BASICS OF FROM-SOURCE SOUND
From-source or just source sound is what you do when you plug in an iPod or a laptop to a sound system or a set of speakers. Here is a list of cables and equipment you need for this:
Mixer
2 main speakers
1/8” or 3.5 mm male to dual male RCA
1/8”male stereo to dual male 1/4” mono
Male to male dual RCA
Male to male 1/8” cable
SOME THINGS TO REMEMBER WITH SOUND
Just because your speaker goes to 10 does not mean that it should ever go to 10.
This will blow your speaker. You never run a marathon at full tilt because you will wear out much quicker.
Speech is different from singing
Understanding speech relies on the high frequency sounds in words. Adjust the high frequency knob on that channel. Without them, it is very mumbled and incomprehensible.
Gain is how much comes into the mixer. Volume is how much gets out.
There is a balance between the two. Some inputs will need more gain while others will need very little.
If you think of the mixer as a “prison guard” and the speakers as the “gate keepers” it will help you understand the basics of how sound works.
Regular vocal and instrument microphones work without phantom power. Most condensers and some other types of microphones need phantom power.
Look for the 48v phantom power button at the top or the back of your mixer if everything is set up properly but the microphone is not working.
If you are using a performance example from Share the Music or any music that pans left and right through your mixer you will need the 1/8”male stereo to dual male 1/4” mono cable mentioned above.
1/8” stereo to dual male RCA will work too but you won’t be able to control its volume separately from the rest of the mix.
Headphone out is the same as speaker out. If you see a headphone jack on an instrument like a keyboard, that is how you plug it into the mixer or into the DI.
Monitors plug into Aux outs and can be controlled separately from each channel.
Performers need to hear themselves, so do kids. If you are using a backing track or any type of accompaniment in a performance, monitors are essential. You may need an end adapter for this.
If you have any questions about anything on here, please do not hesitate to ask.
Until next time, Happy Musicking!