In this video, we're going to spend a few minutes talking about the different types of equalizers and their purposes.
Let's start with an EQ type that you've probably used all your life, maybe without knowing it, the shelving EQ, look familiar? If you've ever turned up the bass or treble on your car radio, you've used something like this.
The name is descriptive. It looks like a shelf, with an entire range of frequencies being affected equally, above or below the frequency being affected.
If you increase the energy in a recording using a high-frequency shelving EQ with 10,000 Hz, and everything from 10,000 Hz and higher would be increased by that same amount. You can also use the shelving EQ to cut a range of frequencies.
There are advantages to shelving equalizers. They are well suited to making very broad natural-sounding changes in the tone of a recording, precisely because they don't focus on a narrow band. When you raise the high frequencies, harmonic's connected with all the instruments will rise together, and remain in proportion. When you increase the low frequencies, all the instruments playing that have energy in the base region rise together.
The peaking or Bell equalizer creates an amplitude change around the center frequency that the EQ is set to. The effect gradually diminishes as you move away from the center frequency or the peak.
The range of frequencies affected is called the bandwidth. Sometimes we call that "Q". This sort of EQ is referred to as a parametric EQ, because you can adjust the frequencies, bandwidth, and the amount of boost or cut independently.
This kind of EQ is very flexible, since it can hone in on particular frequencies by using a narrow band with, or if we use a broad bandwidth, we can make very broad or general changes to the sound of a recording.
In this course and the practice tool, you're going to be practicing EQ ear training and frequency identification, using a peaking equalizer.
Graphic EQs are simple to operate in part because your options are limited. The frequency and bandwidth of each band are fixed, and you can't choose different frequencies. You can only change the boost and cut.
The limitation is helpful when you're trying to make small narrow band changes very quickly, for instance, when you're a live sound environment, but otherwise this kind of EQ is not flexible enough to be generally applicable, for making musical changes.
A filter is a special kind of EQ. It can only cut energy. It uses a very steep slope to allow you to eliminate a whole range of sounds while letting other sounds pass. Like if you had a recording with rumble, you might use a filter to get rid of the low frequency information.
There are high pass filters that take away low frequency signals and let the high frequency signals pass. There are low pass filters that do the opposite. There are not filters that cut signals in a very narrow range, and then pass filters that work as if you're using a high-pass and low-pass filter at the same time. They only allow frequencies in a certain bands to get through.
With a little bit of thinking, you can probably begin to choose the right EQ for a test pretty quickly. Sometimes, the best answer is an obvious, but it's good to have an intelligent starting point to help you get the best result more quickly.
So here are some examples to get you started. If you have a recording that has too much energy on the end of the spectrum too much low-end, or too much high-end, or too little low-end, or too little high-end. You might try using a shelving EQ.
If you're listening to a recording, and a note is popping out. One note is louder than the notes around it. You might try using a bell or parametric EQ.
If you have a lot of mud, say in the body of the acoustic guitar. You might try using a parametric EQ, finding that mud, and cutting it out a little bit.
If you have hum, we have a lot of energy around 60 Hz or 120 Hz. The line frequency of the signal coming from the wall. You might try a notch filter.
If there's a lot of rumble in your recording, you might try using a high pass filter to get rid of all of that excess, non-musical low frequency energy.
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