INDUSTRY
Understanding EQ in Sound Engineering
- Ronak Runwal
- 3 minute read
In the realm of sound engineering, EQ (equalization) stands as one of the most fundamental yet often overlooked tools. This blog post will delve into what EQ is, the different types of EQs available, and how they can be used effectively in various scenarios. We will explore these concepts using a demo track by the band Half Cooked Rice, providing practical examples for better understanding.
What is EQ?
Simply put, EQ is a tool used in mixing that allows you to boost or cut specific frequency bands. You can think of it as a volume control for different frequencies. By manipulating these frequencies, you can enhance or reduce certain elements of your mix to achieve a more polished sound.
Types of Filters in EQ
There are various filters you can use to manipulate frequencies, including:
- Low Pass Filter: Cuts high frequencies while allowing low frequencies to pass through.
- High Pass Filter: Cuts low frequencies while allowing high frequencies to pass through.
- Low Shelf Filter: Boosts or cuts frequencies below a certain point.
- High Shelf Filter: Boosts or cuts frequencies above a certain point.
- Band Pass Filter: Allows a specific range of frequencies to pass while cutting others.
- Notch Filter: Eliminates a very narrow band of frequencies.
- Bells: Boosts or cuts a range of frequencies around a central point.
For a deeper understanding of these filters, refer to our video on the EQ.
Using EQ on Different Tracks
Now, let’s dive into the demo track and see how different types of EQs can be applied across various instruments. The track includes recorded acoustic guitars, bass, distorted guitars, pads, program acoustic guitar, rhythm tracks, and vocals.
Parametric EQ
The parametric EQ is one of the most versatile and commonly used EQs. It allows you to adjust frequency bands dynamically. You can create a point in the frequency spectrum and either boost or cut it while listening to the track. For instance, while listening to the acoustic guitars in this track, I noticed some muddiness that I wanted to clean up. Generally, parametric EQs can be used on any track, including rhythm, piano, vocals, bass, and acoustic guitar.
For this example, I opened the FabFilter Pro-Q3, a fantastic parametric EQ. By double-clicking on the interface, I can create a point that I can drag to either boost or cut frequencies. Different fields allow me to change the frequency, gain, and Q factor, which determines how narrow or wide I want my band to be. I can also choose the filter shape, such as low shelf, high cut, notch, and more. This flexibility makes it an ideal choice for precise adjustments.
Cutting Muddiness
In this instance, I identified a muddiness in the acoustic guitar around the 100 Hz to 500 Hz range. Let’s listen to the acoustic guitar while I cut out this frequency. After applying the cut, the guitar sounds cleaner and fits better in the mix.
Listening in Context
One important rule to remember when using EQ is to listen to the track in the context of the mix rather than in isolation. Soloing a track can lead to misinterpretations of how it interacts with other elements. So, I always recommend analyzing tracks together to understand their relationships and avoid clashes.
Semi-Parametric EQ
Next, let’s look at semi-parametric EQs. Unlike parametric EQs, semi-parametric EQs have fixed frequency ranges and limited controls. However, they often produce a more musical sound, making them a popular choice for many engineers. I typically apply semi-parametric EQs on tracks before using parametric EQs to shape the tone and give character to whatever instrument is playing.
Graphic EQ
Graphic EQs are also useful for tone shaping, especially in live settings. They consist of fixed frequency ranges with sliders for boosting or cutting those frequencies. For example, I often use a Waves API 560 graphic EQ on vocals to enhance their presence in the mix. While applying this EQ, I can boost the highs and cut some muddiness around 500 Hz, resulting in a brighter and more polished vocal sound.
Dynamic EQ
A dynamic EQ combines the functionalities of an EQ and a compressor, allowing for frequency-specific dynamic control. For instance, if you have a vocal track with varying loudness levels, a dynamic EQ can help tame the louder parts without affecting the softer sections. By setting a threshold, the dynamic EQ will engage when the specified frequency crosses that level, providing a more controlled output.
Using Dynamic EQ on Vocals
In this example, I applied a dynamic EQ to control the vocal peaks effectively. As the vocal crosses the threshold, the dynamic EQ reduces the level of that frequency, keeping the vocal balanced within the mix.
Shelving EQ
Shelving EQs are less precise than parametric EQs but are great for broad adjustments. With a low and high point, you can boost or cut a range of frequencies. This type of EQ is often utilized in mastering or group processing to enhance overall tonal balance.
Applying Shelving EQ
For a practical example, I used a shelving EQ on the master bus to boost the highs and cut some low frequencies. The result is a more balanced and polished mix, providing clarity without compromising the overall sound.
Conclusion
Understanding and using EQ effectively can greatly enhance your mixes. By applying the appropriate type of EQ for each track and listening in context, you can achieve a cleaner, more professional sound. As you continue to experiment with these techniques, you’ll discover how to create space for each instrument, leading to a polished and cohesive mix. If you found this information helpful, please subscribe for more educational content on sound engineering!