By M. Erik Matlock • December 7, 2016 Image courtesy of Rory Grant I took guitar lessons over this past summer. I’ve been around bands and music my entire life, and at one point was an unbelievably mediocre bassist. I had enough ability to know the notes on the neck and follow a chart. I was even pretty solid with rhythm and accuracy. But that, as they say, was that. Anyway, the guitar lessons taught me a lot of things that I thought I already understood. They produced enough new information to feel substantially more confident. For example, I can now communicate with guitarists. (In case you ever need a translator…) My guitar teacher is a performing artist, carrying his own sound system and playing the local club circuit. We discovered that his audio engineering skills were a very close match to my guitar playing skills. He knew enough to make noise but had very little sense of control once it was all in place, lacking an understanding of some of the most basic concepts. Like so many of the church techs I trained over the years, he didn’t really know what he didn’t know. The full depth of his struggle was truly revealed when I had to talk him through in-depth troubleshooting over the phone while he was at a gig. It went about as well as you’d expect. Within that semi-panicked hour of his life, desperately trying to figure out why his system wasn’t working, his low level of understanding became painfully obvious. So in the absolute simplest terms, the same that I used with him, let’s go over some essential concepts about a sound system. Please forgive me if this is oversimplified. Know the difference between inputs and outputs. Those two magic words—input and output—are the foundation of setting up a system. Don’t understand the difference between the two? There’s gonna be ongoing problems. The average church or club system typically runs 16 channels or less. The assumption when purchasing a 16-channel mixer is that 16 different microphones, or other inputs, can be plugged into the system. Well, yes and no. Some 16-channel mixers have 16 microphone inputs (or mono channels). Each channel strip, from top to bottom, is identical across the board. Some also offer a few stereo channels, so the mixer might be labeled “16 channels” but you might see less. That’s because the last channels have two line inputs instead of one mic input. Regardless, the manufacturer considers it to have 16 inputs. That’s 16 different points to add a signal to a system. But wait, there’s more… Inputs and outputs are not always labeled that way. Terms like insert, direct out, send, return, tape, two track, aux, control room and even headphones are all points where signals either come into the board or exit the board. Sends allow signal to exit the mixer. Returns are just inputs. Same for anything labeled aux, send or return. One must know the difference to master that mixer. Knowledge truly is power when you have to find creative solutions to overcome limitations. Desperate times often require desperate measures. Yes, I’ve actually been forced to use every possible input and output on an undersized mixer for an oversized event. That ability leads to my next point. Know the limitations of each connection. Just because the manufacturer labels connections. doesn’t mean that’s the only way to use them. Some smaller mixers use terms like effects (FX) or monitor on the auxiliaries. They’re offering suggestions for the most logical way to use them, but it gets irritating once you understand inputs and outputs. Just because a connection is labeled tape return, effects return, 2-track in or out—and so on—doesn’t automatically mean that it’s the only way to use it. Consider the limitations before making that choice. Almost every small church system is set up with some type of playback running into an input, based on its label. But what does it cost you to do that? If you’re completely maxed out, sure. Use it and work around the limitations. If not, consider the other options. Most inputs labeled “tape” or “2TK in” don’t offer all those fun knobs and buttons like the input channels. Rarely will a 2-track input allow adjusting the EQ, padding the signal, cutting low-frequency excess or even adding it to the monitors. So if there’s a regular channel open, use it. Take full control of that signal and mix it properly. Pro consoles don’t tell you how to use inputs. Take off the training wheels and mix. Read the rest of this post 1 2 About M. Erik M. Erik Matlock Senior Editor, ProSoundWeb Erik worked in a wide range of roles in pro audio for more than 20 years in a dynamic career that encompasses system design and engineering in the live, install and recording markets. He also spent several years as a production staff member and team leader for the largest non-denominational church in central Georgia, and served as an author for several leading industry publications before joining the PSW team. http://erikmatlock.com Comments Leave a Reply Cancel reply Your email address will not be published. Required fields are marked *Comment Name * Email * Website Tagged with: Audio Basics Concerts Consoles Engineer Guitars M Erik Matlock Mixing Techniques · all topics Subscribe to Live Sound International Subscribe to Live Sound International magazine. Stay up-to-date, get the latest pro audio news, products and resources each month with Live Sound.