Mastering EQ vs. Dynamics Processing

What actually happens during a mastering session? While many mastering engineers regard the “voodoo” of their art as trade secrets and make clients sign a statement to that effect, I’m more than happy to share what goes on behind the curtain.

Mastering is considered a kind of “black art” practiced by engineers blessed with “Golden Ears”. Some of the best mastering engineers are currently or have been musicians in the past. I know Bob Ludwig at Gateway Mastering was a horn player (those in the know never say “French Horn”…it’s just the “Horn”). I think it’s tremendously important the mastering engineers have a musical background. Would you want some knob-twisting, button pusher left hand brain guy putting the final timbral adjustments on a project that you’ve worked on for many months? I know my clients always felt better that I had such a diverse musical background.

The mastering session is where all of the final mixes are sequenced and tweaked into their final form. A single final “studio master” is created and released to waiting fans and promotion professionals. The one-size-fits-all strategy still rules the commercial music industry.

Two of the most critical steps undertaken by the mastering engineer (in consultation with the mixing engineers and producer) are the application of equalization and dynamics processing. EQ is basically tone controls…only in the mastering studios of the world, they are very expensive, very flexible and very powerful. It’s what we all think of as bass, mids and treble controls…only better. Dynamics processing involves adjusting the overall and relative volume of the tunes or even the internal loudness contour of the albums tracks.

I am a serious believer in the mild use of EQ to bring out subtle elements of a mix or polish off the harshness of an overly bright vocal track. One of my favorite “tricks” is to give about a half dB boost at the first formant frequency to bring the lead vocal into relief. For the male vocals that happens at about 1300 Hz and for females it’s slightly higher at around 1600 Hz. This is the frequency that makes sung lyrics more intelligible…and it never fails to impress the artist and producers.

Other applications of equalization can be applied to the low end of certain tunes to make them consistent with the other tracks. I often shape a snare drum hit at 150 Hz and 1000 Hz to bring out the “snap” of the drum if I think it’s too dull. And of course, there has to be room for it amongst the other instruments. A slight bump at 5 kHz and again at 15 kHz will add some “air” or openness to a track. There are equalizers that have controls out to 40 kHz which engineers use to provide “sheen” or a “glassy” tone to a track.

There are lots of new digital “equalizer type” plug-in in that are on the market these days. They do some interesting things to the harmonic structure of your tracks. Some modify the phase alignment of upper partials to “cloud” the sound make it warmer and others boost the “apparent” level of a certain frequency range by changing the amplitude of only selected elements.

Masterizer was originally an April Fool’s joke by Funklogic but is actually a real plug-in now that “adds low quality effects (static, hiss, etc) to your audio as you fiddle with the controls.” But it does get applied to commercial releases. If the mastering engineer applies it and the producer likes it then you’re good to go.

Following these careful and surgical EQ adjustments, the mastering engineers will begin to apply dynamics processes to the project. We’ll talk about Ultramaximizer, brick wall limiters, side chain compressors and the like tomorrow.

NOTE: If you would like to reply to me with a comment, please consider posting to the webpage at REALHD-Audio.com instead of sending me a personal email. You can add your comments for this article at the bottom of the page at Post comment here.