Use Psychoacoustics to Craft a Huge-Sounding Mix

Psychoacoustics is all in your head—it’s the branch of psychology concerning the perception of sound and its physiological effects.

Fig. 1. iZotope Nectar adds pleasing harmonic distortion to vocal tracks to make them sound louder and bigger.



Psychoacoustics is all in your head—it’s the branch of psychology concerning the perception of sound and its physiological effects. Using the principles of psychoacoustics, you can trick your listeners into thinking a mix sounds louder, wider, and deeper than it really is. Use these mind-bending tips to create an enormous- sounding mix.

Detonate The Chorus

Psychoacoustics dictates that abrupt sounds seem louder than those that build slowly to the same level. It is the sharpness in contrast between silence and peak level—and how quickly that transition occurs—that creates the impression that something is really loud.

If you want your mix to explode into the chorus— or “hook”—of your song, hold your fire during the verse and subchorus. Don’t introduce additional instruments gradually as the song approaches the chorus. Wait until the downbeat of the hook to pile on extra tracks. Try introducing some percussive tracks when the first chorus begins. You might even consider muting all the drums until then. And if the song allows, consider having a half or full bar of silence (a musical rest) right before the downbeat of the chorus. The abrupt onslaught of additional tracks right after the peaceful calm will make your song’s hook erupt with shock and awe.

Distort One or More Tracks

Play back—at the same level on your meters—two pre-recorded electric guitar tracks, one clean and the other overdriven with distortion. Which sounds louder? Unless the clean track is significantly brighter than the distorted one, your brain will always tell you the distorted one is the loudest. Distortion tricks the brain into thinking something is very loud, even when it’s not.

Electric guitars aren’t the only tracks that benefit from this sleight of hand. If you can’t make your vocal track loud enough to command your mix without clipping, try adding a dash of distortion. The goal isn’t to make the vocal sound noticeably fuzzy or dirty but to add just enough harmonics to make it sound louder. The SPL TwinTube, Soundtoys Decapitator, Softube Focusing Equalizer (part of the company’s Passive- Active Pack bundle), and iZotope Nectar plug-ins are all outstanding for this purpose. (See Figure 1.) Add a little bit of plug-in processing to the vocal, and it will sound louder and bigger than the dry vocal at the same output level.

Put It Off Until Later

Fig. 2. Some delay-modulation plug-ins, such as MOTU Chorus, allow sufficient parameter controls for you to create the Haas effect.


In last month’s Techniques article “Learn How to Space Out,” I discussed how adding pre-delay to a reverb patch makes the resulting virtual acoustic space sound farther away. The longer it takes for a sound to arrive in your ears, the farther away the brain interprets that sound’s origination to be. But to complete the mental picture, you must also account for a real-world phenomenon called high-frequency transmission loss. This acoustic effect dictates that the farther a sound travels through air, the more its high frequencies will be attenuated.

The longer the pre-delay you program into your reverb patch, the more highs you should roll off the reverb return using either a low-pass filter (LPF) or high-shelving cut. That is, as the pre-delay’s time in milliseconds increases, progressively lower the corner frequency for your LPF or shelving EQ. Doing so will add natural and convincing depth to your mix and trick your brain into thinking the sound is coming from behind your speakers! To fool your brain most effectively, make sure some other elements of your mix are mostly or completely dry. It’s the contrast between dry and delayed sounds that tricks the brain into thinking one thing (the dry track) is very close to you and another (the pre-delayed reverb) is farther away. You can’t create a sense of depth if everything is far away.

Make It Wide Using the Haas Effect

Just as delay can make something sound deeper, it can also be used to make a track sound wider. Hard-pan a mono keyboard comp part or rhythm guitar track to the left and bus the track to an aux channel via a send in your DAW’s mixer. Insert a delay-modulation plug-in on the aux channel. Hard-pan the aux to the right, set the plug-in’s output to 100% wet, and set the delay time to around 7 milliseconds. Now program a very slow and shallow modulation of the delayed signal: Set the plug-in’s speed or rate control to around 0.8Hz and its depth or width control to roughly 17%. Modulating (cyclically varying) the delay time in this manner makes the track’s delayed component sound alternately closer to and farther away from its dry sound in the opposite speaker, tricking the brain into constantly shifting the stereo image. The resulting Haas effect will make your mono track sound stereo and add subtly shimmering movement between left and right speakers. MOTU’s Chorus plug-in (for Digital Performer) can easily create the Haas effect, and it sounds terrific. (See Figure 2.)