How to Troubleshoot Audio Problems

Video Transcript

"Hi, my name's Kip and I'm here on behalf of Expert Village. And this clip we're going to go over a simple technique to begin to troubleshoot when we're having an audio problem and often times that problem is related to our cabling. Let's say, for instance, we're getting a hum in our final output and we've been able to determine by turning the channel faders up and down, that we're getting that hum through channel nine. Now, the first thing to do is to decide which direction to start looking for that hum, is to take and unplug channel nine and see if it goes away. If it goes away, likely, it's in this cable. The next thing that I will do is to take channel eight, or one that's next to it that is not humming and plug it into channel nine. Once I plug that into channel nine, if the hum stays away, then I am even more sure that it's in the cable or in the microphone. The next step is to plug the one that was humming into channel eight. If the hum transfers to channel eight, then I am absolutely sure that problem is going upstream of the audio signal. If it doesn't follow, if the hum stayed in channel nine, then I know that even though I reversed the microphones and the hum stayed in channel nine, then I know that the hum is downstream with the signal flow. So, then I have to start looking in my mixing board and on through the signal change, through my EQs and so forth. I'm often called in to do a job because the church - because I work primarily with churches, but also with businesses and clubs on occasion - is having trouble with a hum or a buzz or an intermittent audio problem and they're having a hard time isolating what the problem is. And so this is the technique that works best for me. Now if you determine that if your problem is from the mixing board towards the speakers, then you'll want to use the same process. Is the hum coming, for example, from the left channel and not the right, or the right and not the left? Or from both? Is it in one of the components - graphic equalizer, compressor limitor - and so it's really easy just to bypass those. Not just hit the bypass site, but actually unplug them and bypass them physically. If you listen very carefully to the sound put off by the transformers in a fluorescent light, that is a sixty cycle hum. If the tone of the hum is very similar to that of a fluorescent light, then you may have a ground problem in your actual AC - the electrical plug-in. And to troubleshoot that, you can - although it's not advised - you can briefly put a ground lift on there and see if that goes away. What I prefer to see you do is take a long extension cord that you know absolutely is on a different circuit and plug in your audio system and see if the sound, the humming, goes away. And if it doesn't go away and you've determined that it's a ground problem, call your electrician and have them come out and check the ground and preferably install an independent ground for your audio system."