Why is Gain Structure So Important?

Gain Structure:
Why You Insert the Main EQ at the L-R Insert Point vs Daisy-Chaining the EQ into the Signal Path After the Console.

Does that sentence make any sense at all to you? If you want to master your Gain Structure, it should. If that statement doesn’t make sense and you mix live music on a regular basis, you need figure it out fast! Improperly routed audio signals will be degraded significantly and therefore your mix will be degraded as well. Here's why:

The insert point at the L_R output of most consoles is a calm and collected +4dB max, even when the console output meters are at 0dB. The metering point is AF(after fader). But here's where things change because the the L-R output goes from the fader to an output amplifier that juices the signal to as much as +12 or +16dB! If you daisy-chain the Eq after the console and run the console at 0dB output, you are slamming that +12dB signal into a +4 device. What do you think will happen?

In Live Sound Engineering 101 you are going to learn the whys and hows of setting up gain structure correctly. Gain structure in a mixing console works within the dynamic range that a PA or monitoring system is capable of reproducing. Gain structure, dynamic range and headroom are all closely related concepts. There is a method for setting the gain structure in a console that will guarantee that you never clip or over-saturate critical components in the signal path. Avoiding subtle clipping and over-saturation in the signal path is critical to high quality mixes.

To achieve the correct gain structure one must thoroughly understand the nature of audio signals, the different types and different signal levels involved. You must understand the correct process to meter or measure the signals as they flow through the signal chain. Metering via VU meters and the correct configuration of buttons allows one to monitor those signal levels anywhere in the console and this is crucial to getting it right. Learning the methods to use in these complicated monitoring schemes can make a world of difference in the way your mix sounds.

Join me in Live Sound Engineering 101 to learn about gain structure, compressors and gates and advanced techniques I use to achieve really high quality sound!