Lucky 13 Vocal Processing Tips

Find Your Own Voice with Vocals

by Craig Anderton

Yes, you already know about equalizing voice, and how to choose the right mic to flatter a singer. But you're an esteemed visitor to Harmony Central...you want more, better, bigger, and further. This baker's dozen of tips will help take your vocals up one more notch.

1. THE COMPOSITE VOCAL FIX

 You want a doubled vocal part, and have loop-recorded a vocal on multiple tracks so you can pick and choose among the best bits to create two killer tracks. Unfortunately, for one short phrase, only one track has the perfect take -- maybe the others have flaws, or the singer "hit the jackpot" and couldn't duplicate it properly. Don't worry: Copy the perfect part into the other track, shift its pitch a tiny bit, then delay it by 20-35 ms.

2. OPTIMIZE REVERB DIFFUSION

Great vocals demand great reverb, so try low diffusion ("density") parameter values. Here's why: Diffusion controls the echo "thickness." High diffusion places echoes closer together, while low diffusion spreads them out. With percussive sounds, low diffusion creates lots of tightly-spaced attacks, like marbles hitting steel. But with voice, which is more sustained, low diffusion gives plenty of reverb effect without overwhelming the vocal from excessive reflections.

3. OPTIMIZE REVERB DECAY

Many reverbs offer a frequency crossover point, with separate decay times (RT) for high and low frequencies. To prevent too much competition with midrange instruments, use less decay on the lower frequencies and increase decay on the highs. This adds "air" to the vocals, as well as emphasizes some of the sibilants and "mouth noises" that humanize a vocal. Vary the crossover setting to determine what works best for a particular voice.

4. THE BEAUTY OF AUTOMATED PANNING

With doubled vocals, panning both to center, or panning one more left and one more right, gives a very different overall effect. For example, if background vocals are part of the picture, I almost always put the voice in the center. If I want the voice to cede some of its prominence to the instruments, I'll spread the two tracks out a little bit to "unfocus" the vocal. Use automated panning to set the vocals as appropriate for particular parts of the song.

5. CREEPY VOCALS

Remember those creepy, whispery type vocals that Pink Floyd used to do? Try this one on vocals that are more "spoken" than sung, e.g. rap. Plug in your vocoder (software or hardware), use voice as the modulator, and pink noise as the carrier. You may need to reduce the pink noise high frequencies somewhat. Mix it well behind the vocal -- just enough to add a creepy, whispery element. Also try delaying it by some rhythmic value, then adjusting its level as appropriate.

6. SELECTIVE ECHOES

I very much like synchronized echo effects added to voice, but only for specific words and passages. You can do this with automated aux send controls; put synchronized delay in an aux bus and turn up the fader when you want delay. This is best if you want apply the same effect to multiple tracks. Or, cut the parts you want to echo, paste them in another track in the same position, and add synchronized delay to that track. This is preferred if you have a limited number of aux buses.

7. STEP UP TO THE PLATE

If your digital reverb has multiple algorithms, try using a plate-based preset for voice. In the "old school" days of recording, plate reverbs were often favored for vocals over chamber reverbs, which were used on instruments. "Real" plates have a tighter, somewhat brighter, less diffused sound that works well with vocals. Of course, there's no guarantee your reverb's plate algorithm actually sounds like a real plate, but give it a shot.

8. SHIFTY PITCHES, PART 1

If your studio has digital tape (e.g. ADAT), there's probably a variable speed control. Use this to thicken doubled vocals; when you record the doubled vocal, speed up or slow down the tape a bit so that this vocal has a slightly different timbre when you play it back at the normal pitch. One caution: if you speed up the tape for a lower-pitched sound, the timing of the performance had better be extra good. Slowing the tape down magnifies any timing discrepancies.

9. SHIFTY PITCHES, PART DEUX

This trick is as old as the Harmonizer (trademark Eventide), when engineers discovered that shifting pitch downward 10 to 15 cents, and mixing the harmonized signal behind the straight vocal, added a useful thickening effect. You can do this with any digital pitch-shifting processor, hardware or software. If you're planning to triple the vocal, shift up the second pitch shifter by an amount equal to the downward shift. When tripling, you may want to increase the overall amount of shift.

10. GET DOLBY OFF UNEMPLOYMENT

At one time, Dolby Noise Reduction units were used in studios to reduce noise with analog tape. But they also were used on a lot of background vocals to give an airy, bright sound by encoding with Dolby (usually type A) while recording, but not decoding on playback. What Dolby did was compress above a certain frequency and add pre-emphasis, which is ideal for souping up a vocal's intelligibility. It's not all that easy to find old Dolby units, but when you do, they tend to be dirt cheap.

11. SAY HELLO TO VOCAL PROCESSORS

Vocal processors, by companies such as TC-Helicon, Antares, and DigiTech, provide a whole bunch of vocal effect functions, from harmonies to weird vocal formant shifting that can turn choirboys into crusty blues singers (and vice-versa). The harmony functions are also useful, and few people are aware of what these things do with toms. If you record a lot of vocals, or do voiceover work, these powerhouse processors offer a really deep bag of tricks.

12. MAXIMIZE OR COMPRESS?

It's common knowledge that most pop vocals are compressed to some degree. Lately, though, I've been doing very light compression while recording (just enough to smooth out some of the more abrupt level variations), then using loudness maximizer-type processing (e.g., Waves, iZotope Ozone, or Wave Arts processors) on mixdown. To my ears, this gives a more "raw" sound (as opposed to "smooth") than using compression alone. This seems particularly effective on rock vocals.

13. MODULATION ECHOES

Okay, we like echoes on voice. A somewhat rare feature in digital-land is the ability to modulate delay time slightly. This "feature" was an inherent part of tape echo, as the tape speed was never perfect. If your delay doesn't offer modulation, you can simulate the same effect by splitting off the delayed sound through a chorus or flanger set for a short delay, with a very slight amount of modulation (try a random modulation source if possible).

Craig Anderton is Editor Emeritus of Harmony Central. He has played on, mixed, or produced over 20 major label releases (as well as mastered over a hundred tracks for various musicians), and written over a thousand articles for magazines like Guitar Player, Keyboard, Sound on Sound (UK), and Sound + Recording (Germany). He has also lectured on technology and the arts in 38 states, 10 countries, and three languages.