Recording Vocals, Part 4: EQing Vocal Tracks

By David Franz

Over the past several months I've discussed recording and editing vocal tracks in Pro Tools, from capturing the best sound to getting a great performance to editing together the best parts into one solid, emotive performance. But even with all that work, there's still more to making a vocal track shine. Let's jump right into mixing techniques for vocal tracks.

Chopping the Timbre
In almost every song with vocals, the instrumental tracks in the mix are subordinate to the lead vocal track. The lead vocal must cut through the mix — its clarity is the primary focus.

There's a problem, though. Many instruments in a mix share common frequencies. Almost every instrument in your mix (including the human voice) consists of multiple frequencies, and those frequencies overlap. Even if an instrument is only playing one note (the fundamental pitch), it also generates additional pitches with lower amplitudes (known as harmonics and overtones) that color the overall sound and define the instrument's timbre. These frequencies can interfere with the clarity of the vocal track in your mix. Enter equalization, also known as EQ.

There are two main reasons to apply EQ: First, to adjust the frequency content of a sound (its timbre) so that the sound is more subjectively appealing in the overall mix, and second, to make room for certain instruments to cut through the mix. This is sometimes called "carving EQ holes."

Carving the Holes
It's a common practice to carve EQ holes to make room for the primary frequencies in specific tracks. For example, if you want to enhance the sound of both the kick drum and bass tracks without having them compete, you can boost and/or cut different frequencies within each of their ranges. In this case, you might boost 60 Hz on the kick and 100 Hz on the bass, then cut 100 Hz on the kick track and 60 Hz on the bass. Doing this will create EQ holes for each instrument and add clarity. (Note: I am not saying that each instrument should have its own dedicated frequency range in a mix. Instruments will continue to share frequencies, but clearing a path for the predominant frequencies of certain instruments can "open up" a mix.)

This technique also applies to vocal tracks. Vocal intelligibility is mainly found in the 1 kHz to 4 kHz frequency range. Carving out some of the overlapping middle frequencies on your guitar and keyboard tracks can make room for the lead vocal to shine. You can go one step further: Boost the vocals in this range while attenuating the same frequencies in the rest of the instrumental tracks, to make the vocals stand out while maintaining a natural overall blend.

Tweaking the Freqs: Basic Techniques
Not all vocal tracks need to be EQ'd. However, it is common practice to bring out certain frequencies to improve a vocalist's overall sound, as well as to create a more emotive performance.

	The T-Racks EQ plug-in comes loaded with many presets, including the "Male vocal air + body" preset shown here Click to enlarge

Pro Tools comes with two DigiRack EQ plug-ins, a one-band and a four-band parametric EQ (in both mono and stereo varieties). You also get IK Multimedia's T-Racks EQ plug-in (Figure 1). Try using these plug-ins to sculpt your vocal sound.

Using Your IQ to EQ
Because everyone has a different-sounding voice, vocals are one of the most challenging "instruments" to EQ. Vocal range and gender affect the recorded track most, but EQing at the frequencies in the following table will can really improve the sound of a vocal performance.

	Here's an example of some slight EQ tweaks for a male singer I record on a regular basis. Click to enlarge

• To increase brightness and/or open up the vocal sound, apply a small boost above 6 kHz (as long as it doesn't affect the sibilance of the track).

• Treat harsh vocals by cutting some frequencies either in the 1 kHz to 2 kHz range or the 2.5 kHz to 4 kHz range to smooth out the performance.

• Fatten up the sound by accentuating the bass frequencies between 200 Hz and 600 Hz.

• Roll off the frequencies below 60 Hz on a vocal track using a high-pass filter. This range rarely contains any useful vocal information, and can increase the track's noise if not eliminated.

• Create an AM radio or telephone vocal effect by cutting both the high frequencies and those below 700 Hz, while dramatically boosting frequencies around 1.5 kHz.

• Add airiness to a vocal track by gently boosting 13 kHz to 14 kHz.

• Adjust the formant frequencies.

Formant? What's a Formant?
You can use a singer's formant frequencies to your advantage to help a vocal part really stand out. A formant is an area of special resonance within a vibrating body — in this case, the singer's vocal tract. Because every singer's vocal tract (vocal cords, mouth, nose, tongue, lips, etc.) has a slightly different structure, the formant of each person's voice is unique. Even when the pitch changes, the formant stays the same, giving that person's voice its own characteristic sound. (Instruments also have formants, by the way — it's not just voices.)

For men, the main formant range is around 2.5 kHz to 3 kHz, while in women, the range is roughly 3 kHz to 3.5 kHz. There are also low formant ranges: 500 Hz for men and 1 kHz for women. With these formant values in mind, try adjusting the EQ of the vocal track around these frequencies and see what results you achieve.

	Use the DigiRack DeEsser plug-in to eliminate unwanted sibilant sounds in your vocal track. Click to enlarge

The Threshold parameter sets the level at which the frequency-specific compression is activated. Set this level so that only sibilants trigger the de-esser — otherwise you may create unwanted compression and gain reduction on the track.

Some Final Thoughts on EQ
When you're working with EQ on vocal tracks, it helps to keep a few things in mind:

• Not many people can hear a boost or cut of 1 dB or less when altering the EQ on a sound. In fact, most people won't even notice a 2 dB to 3 dB change (except people like us). However, subtle changes like these are often very effective. Large changes in EQ (boosts/cuts of 9 dB or more) should be avoided in most cases, unless an extreme effect is desired.

• Instead of automatically boosting a frequency to make it stand out, always consider attenuating a different frequency to help the intended frequency stand out. That is, try "cutting" a frequency on another track rather than boosting the track you want to emphasize.

• Be aware that any EQ settings you change on a particular instrument or voice will affect not only its sound, but also how the sound of that instrument interacts with all the other tracks in the mix. When altering EQ, don't listen to the track in solo for too long (if at all). You may make the track sound great on its own, but it might not work with the rest of the instruments.

Like what you see in this column? Check out my book, Producing in the Home Studio with Pro Tools (2nd Edition). You can buy it online right here through Digidesign's web store, or visit www.protoolsbook.com. Interested in personal instruction on Pro Tools from yours truly? Visit www.berkleemusic.com and learn about several amazing Pro Tools learning experiences available online though Berklee College of Music. Wanna see my studio and hear some samples of my work? Visit www.undergroundsun.com.

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