Applying equalization

In Chapter 5, Sound Design and Audio Envelopes, we learned that frequencies are related to the pitches we hear. By increasing the frequency, we increase the pitch of a sound.

Equalization (shortened to EQ) is a category of filter effect used to increase or decrease targeted frequencies of a sound. EQ is used to enhance the frequencies of sounds you like and reduce those unwanted ones you don’t.

One way that EQ can be used is to clean up muddy mixes. When multiple instruments are playing, instruments may sound like they’re trying to play over one another. The overlapping of sounds makes it difficult to hear any of the competing instruments clearly. This is known as mud in the mix and is undesirable. EQ can help fix muddy mixes by removing competing frequencies of instruments playing at the same time. This helps to designate an area of frequency space for each instrument so that you can hear each one clearly. This is known as cleaning up the mix or removing the mud. The result is a desirable, clearer sound.

FL Studio comes with an excellent EQ plugin called Fruity parametric EQ 2. It has lots of features to satisfy most of your EQ needs. Let’s use Fruity parametric EQ 2 to demonstrate how to apply EQ to your sounds:

1. Route an instrument or sound sample to an empty mixer track and add the Fruity parametric EQ 2 effect.
2. Play your sound. When your sound is played, your plugin will look like it does in the following screenshot:

   

   Figure 6.14 – Fruity parametric EQ 2

   The EQ plugin visually shows the frequencies of the sound as orange/pink vertical lines. Louder frequencies will appear brighter and quieter ones duller. Directly below the frequency visual, you can see a scale of frequencies ranging from 20 Hz to 10k Hz. Above the frequency visual, you can see the note pitches and labels associated with the corresponding frequencies.

   Along the horizontal line in the middle of the frequency visual, you can see circle icons with the numbers 1 to 7. Each of these icons is supposed to represent a frequency range known as a band. You can drag these band icons with the mouse to move them. The bands allow you to increase or decrease the sound of frequencies at the corresponding position.

3. While playing your sound, left-click on one of the EQ bands and drag it upward. You’ll notice that the sound increases in volume in the area of the affected frequency. This is known as boosting the frequency. Dragging the band down will decrease it. This is known as cutting the frequency.
4. When used in practice, you want to experiment with increasing and decreasing EQ bands to increase frequencies that you like the sound of and reduce those that you don’t.
5. A way to determine offensive frequencies is to select a band and increase the value. Then, move the band (sweep it) left and right to find the frequency that is most offensive. For example, you may find that at a certain position, you hear undesired shrill whistling. At this position, experiment with decreasing the level of the band below 0 dB. The amount to reduce will depend on your specific scenario. The hope is that this will cut out the offensive frequency sound.
6. On the EQ band that you moved upward in position, hover over the band and scroll with your mouse wheel. Doing so will adjust the slope of the EQ band fading in. The slope makes the change in frequency more or less abrupt. The terminology associated with adjusting the slope is known as bandwidth (Q). You can adjust the slope (bandwidth) to make it wider or narrower.
7. Right-click on the same EQ band. A menu of additional features will appear, as shown in the following screenshot:

Figure 6.15 – EQ passes and shelves

By default, the type of EQ band is set to Peaking and allows us to add or reduce specific frequencies. You can see that there are other options types for pass, stop, and shelf.

A pass is a filter that restricts which frequencies are allowed. Only frequencies within the pass filter range will be heard. A low pass only allows frequencies that are below the filter. A high pass only allows frequencies that are above the filter. A stop is where all frequencies in the chosen band are removed. A shelf is where you increase all frequencies that occur within the shelf filter range.

Passes are very useful. Instruments are intended to occupy a specific frequency range. The scale above the frequency visual has labels for common frequency ranges: SUB, BASS, LOW MID, MID, HIGH MID, PRS, and TREBLE. Outside of the frequency range, instrument frequencies may be competing with other instruments, which could result in muddy mixes. In such cases, it is advised to consider adding a pass to remove the unneeded frequencies. This can help to prevent muddy mixes. For example, a sub-bass instrument likely benefits from a low pass filter. This removes high frequencies from the instrument and helps prevent the sub-bass instrument sound from overpowering higher instruments’ sounds.

The Band menu has an Order option. Order lists various slopes into the band. This does the same thing as hovering over the EQ band and scrolling with your mouse wheel.

The final Band menu option is the Key category. Since frequency is the same thing as pitch, you can choose to increase or decrease specific pitches. By selecting a specific pitch in the menu, you can choose an exact pitch position for an EQ band.

The right side of Fruity parametric EQ 2 has knob controls for precise control over individual bands. Moving the sliders up or down allows you to move the frequency bands.

At the top right of Fruity parametric EQ 2, you’ll see a menu of presets. I encourage you to experiment with presets to see examples of the EQ possibilities.

At the bottom of the plugin, you’ll see the options and settings. One worth mentioning is the COMPARE button. This allows you to flip back and forth between two states of the plugin. It can be used to show a before-and-after state to see whether the EQ improved your sound.

EQ best practices

The fewer instruments you have playing at any given time, the less likely you are to run into competing frequencies. If you add in a lot of instruments playing simultaneously, you’re going to have to spend more time with the EQ to carve out and create frequency space for each instrument.

Your ears pay more attention and can more easily detect changes in high frequencies than in lower frequencies. You only ever want to have one instrument at a time playing in the sub-bass frequencies. Your ears won’t be able to distinguish multiple melodies going on in the sub-bass region. Consider using a high pass filter on everything that is not a bass instrument.

EQ general rules

Here are some general EQ suggestions:

• Cut frequencies if you’re trying to make things sound better. Best results are usually achieved by eliminating offensive elements in a mix.
• Boost frequencies if you’re trying to distinguish sounds from each other.
• Find the most important element in a song and emphasize it. Everything else acts as support. Competing frequencies should be removed. This leading instrument element may change throughout the course of the song, for example, from vocals to a guitar solo. You’ll usually want to create frequency space for the vocals and favor them over other instruments.

When two instruments are playing at the same volume and occupy the same frequency range, they are competing for attention. To fix this, consider the following potential solutions:

• Consider putting one of the instruments in a different section. Mute one competing instrument and bring it in later.
• Set one of the instruments further back through the use of reverb.
• Focus each instrument on its own frequency and tailor the offending instrument to focus on a different frequency range.
• Pan the competing instruments to different locations.

The following is a list of terminology commonly associated with frequency ranges. For example, if an audio engineer says that a sound feels muddy, they’re probably referring to the range around 250 Hz:

Figure 6.16 – Frequency range terminology

You can use this terminology when you are collaborating with another musician on a song mix and need to refer to a specific frequency range.

Acoustic instruments generally occupy a set range of frequencies. The following chart shows some examples:

Figure 6.17 – Instrument frequency chart (source: https://commons.wikimedia.org/wiki/File:Estensione_Strumenti_Musicale.jpg)

When thinking about mixing, you generally want to only have a minimal number of instruments occupying the lower bass frequencies at any one time, as these tend to blur with one another. If you must have competing low-frequency instruments playing simultaneously, this is where sidechaining can come in handy so that the instruments don’t compete with one another.

In this section, we explored Fruity parametric EQ 2, which is a parametric equalizer. Parametric means that you have continuous control over the frequencies and can adjust any chosen frequency. It should be mentioned that there is another type of equalizer, called an analog equalizer, and you will likely come across many of these plugins. In the beginning, before digital audio workstations, all equalizers were analog equalizers. Analog equalizers allow you to adjust frequencies of sounds just like parametric EQs but are restricted to predetermined frequency intervals.