Ok, I know what you're thinking: what the heck do equalizers and ice sculptors have in common?
These artisans always start with the same raw material: a giant block of ice. After having a vision for what they want to transform to the block into, they use several specialized tools to slowly chip away at the block until they're happy with its shape.
They cannot add anything back to the ice. No undo button. They carefully carve away chunks of the ice until they have created something beautiful.
Why not work this way in mastering? We should ask ourselves, "Does anything need to be chipped off? If so, do I need to work with a chainsaw, a chisel, or a mallet?"
You might have guessed that the analogy I'm trying to make compares ice sculpting to subtractive EQ. I believe this approach does three advantageous things for you:
1. Saves Headroom
Headroom. A valuable resource often overlooked. I often beat my head against the wall and wonder why some mixers choose to use every single one of the 144 bits available to them. You might as well fill your morning coffee mug to the brim and expect a quick jog down a set of stairs will go just dandy.
Ahem...where was I.
Although it is still possible to "add" energy to a signal when using subtractive EQ, cutting instead of boosting decreases the level of an audio source. If a loud master is what you're after, trimming the fat on a track can help you get the overall level louder before you start compromising its sonic integrity.
I typically will do subtractive EQ first, then farther down the signal chain I'll use additive EQ to shape up anything that needs addressing.
2. Reveals All "The Good Stuff"
When done right, tasteful subtractive EQ removes all the junk in a mix and leaves alone what sounds great. I usually find that one or two subtractive EQ moves often unlock the mix and really let its strong points shine through.
For example, too much energy in the low mids (200-500Hz) often clutters up a mix and reduces your depth of field. Even a 1dB cut with a fairly wide Q can clarify that range and instantly give you more front to back separation. Yes, you heard me right. EQ alone can shape your stereo field.
By no means is "cut 300Hz" a part of a robotic checklist that I work through on every master, but knowing that this EQ move can sometimes solve both a tonal balance and a stereo imaging issue makes my workflow more efficient and effective.
3. Keeps You Focused
It seems that we as humans jump at the opportunity to add something. We want to put our trademark on what we've done and feel like we've contributed. Adding more to something feels exciting. Given this gut level inclination, subtractive EQ feels counterintuitive.
For some reason I find myself working with more precision and intentionality when I use subtractive EQ. Again, subtractive EQ is simply one tool in my toolbox that I use to get great masters, but sometimes a half dB cut can really open up a track.
Much like an ice sculptor has a vision for his work and carefully shapes her ice block to fit that, we should do the same with how we master.
Be bold. Take some chances. Unlike the sculptor, we have Command + Z. I'd challenge you to try mastering a track by using subtractive EQ exclusively. I guarantee it will become a tool you never want to be without.