Tech Tip #4: Sound Systems

The ProAV article, “How to Troubleshoot a Sound System” by Dan Daley inspired me to elaborate on how to work with a sound system that’s not cooperating. Any given system has the potential to give you and your audience a headache, but here are some tips that can lessen trouble shooting time during setup as well as ease your woes.

First, here’s a synopsis on how a sound system works. Audio technicians add layers of extra equipment to enhance the sound for every room and situation. Usually, technicians forget the basics. Every system follows the same route no matter how you set it up. All sound systems have a source of sound. Whether it is a microphone, CD/DVD player, MP3 Player, or computer, there needs to be something to amplify. The flow of audio travels to some kind of mixing device. Once mixed, it travels out of the mixer to sound manipulators. Sound manipulators consist of compressor / limiter, noise gates, effect units, delays and so on. After the sound is manipulated, it travels to the amplifiers. Finally the sound is broadcasted through speakers to the audience. When trouble shooting a sound system, always check the source first. Think in terms of separate areas - departmentalize where the trouble might be (ie. Source – Mixer – Manipulator – Amps – Speakers).

Next, look deeper into each department. Start with the source and think about the main problems that arise. The usual suspect is cable. Every sound technician should treat each cable like an expensive piece of gear. It's a pain, but bench test all of your cable after every use. Even open the ends and check every soldered connection to see if your cable is loose or if the solder is beginning to break away from the connector. Paying attention to your cable will greatly reduce setup time, every time.

The mixing console can seem intimidating. This can be easy. Nothing is infallible when electronics are involved, and with your mixer, channels can go bad. When you know that your source and cable are properly working, you should be able to visibly see some kind of meter, LED lights or analog needle, on each channel. If you do not “see” sound coming into the channel, switch channels on the board. This swapping will most likely solve your input problem. The same should be considered with your mixer’s output. Although specific distribution of sound is sometimes required to specific events, uncooperative outputs might mean that you need to make some creative adjustments.

Sound manipulation pitfalls also happen when a technician adds multiple devices between the mixing and amplification stage. With sound manipulation, there are usually two concerns that arise when trouble shooting a system, broken gear and swapped input/output. After you have looked at your mixer, bypass all of your manipulators and go straight to the amps. If you can hear sound, add each manipulator in line one at a time to find your trouble piece of gear. When setting up your system, keep close attention to your wiring path. Make sure that you have the correct cable connected to the correct input/output.

Amps are usually overlooked and can be the problem too. Power regulation, airflow, and cabling are usually at the root of amplifier problems. Double check to make sure that your amps are able to pull the amount of power recommended for the unit. Amps can also overheat – so check to make sure they are well ventilated.

Remember, speaker and amp selection go hand in hand. Overdriving your amps can cause catastrophic failure to your speakers. Make sure that when your system is setup and all your connections are made, you ease the sound into your speakers. You might be looking for replacements if you don’t.

These tips should help you figure out how to get your sound system back on track at your next meeting. Feel free to contact me at 815.469.1422 or info@warnerav.com for advice on your next meeting or event.