How to use PA equipment EQ

2020-05-05

Theme：PA

Have you ever wondered about a particular mixer function?
I briefly discussed how to use a mixer in a previous blog, but this time I will briefly explain the equalizer.
What’s a mixer? If you’re interested, please check out the previous blog.
→ PA equipment course that you can't hear now How to use mixer

This time I'll use the soundcraft/EPM6, a slightly larger analog mixer than the Notepad I used previously.

Soundcraft / EPM6

■ EQ

I already mentioned the name, but this time I will explain this section. This section is called the equalizer, commonly called EQ. It is an audio device that changes the frequency characteristics of audio signals (from Wikipedia), but honestly, what does that even mean? To put it simply, it is a convenient tool that changes the way the sound is heard. By the way, the EPM6 EQ has 4 knobs. From top to bottom, HF (HIGH Frequency), MF (MID Frequency; two knobs), and LF (LOW Frequency). Frequency is related to pitch. In other words, HF = high frequency = high pitch. You just use the knobs at each height to boost (volume up) or cut (volume down). For example, if you’re practicing a song and find you have some pain in your ears and you feel like you’re sick, it may be that many high-pitched sounds (high frequencies) are being emitted, and this may be noisy. In that case, you should cut the HF.

The pitch (frequency) of the sound that can be adjusted depends on the mixer. In the case of the EPM6: HF is 12kHz, MF is variable, and LF is 80Hz. It is one of the factors to consider when selecting a mixer. With the variable type, you can change the frequency to be adjusted, just like the name. The MF knob allows you to select the frequency from 150Hz to 3.5kHz. Adjust the boost, and cut with the lower knob.

Mixers like the EPM6 on which you can adjust three frequencies are called 3-band EQ. Depending on the mixer, there are various types such as 2-band type only for HF / LF and 4-band type for HF / HMF / LMF / LF. Below is a visual representation of the EQ settings. I think that it is easy to understand if you look at this.

EQ setting image

In this figure, HF ④ is boosted (knob is twisted to the right), MF ③ is cut (knob is twisted to the left), and LF ① is boosted (knob is twisted to the right).

I think some people practicing in the studio don't really understand how to use the EQ, even if the permanent mixer is equipped with it. In such a case, take some time and try playing around with the knobs turning them slowly. Please note that feedback may occur if you boost too much.

At first, the trick is to think of EQ as something that basically cuts. If you forcibly boost (increase), it will not only impair the texture of the sound, but will also disturb other sounds and cause distortion. This is an important point to keep in mind not only during recording but also during live performances.

When you get used to it, try boosting and try to create the sound you like best. If you don't understand right now, for the time being, keep the EQ flat with all knobs set at 12:00. The moment you recognize the sound has changed when playing with the EQ, it gets to be a lot of fun.

The EPM series featured this time is highly recommended for everyone, from beginners to intermediate users. Please try controlling the sound with your own hands.