Mixing aggressive music is an entirely different skill set now days than mixing traditional electric-guitar based music. The production standards have changed, and they vary greatly. The common thread between Metalcore and Rock is that they both feature powerful drums, loud vocals, and screaming guitars. But what's the difference?
In Metalcore, kicks must be captured in a much more detailed way as the type of drum parts will have quicker kicks. In rock, you find much more steady parts with much more space between kick hits. In Metalcore, you'll find a kick can go from being 1 or 2 beats a bar to 16 beats on the next bar. This poses an interesting challenge not only for production, but also in the mix. In the real world, a kick drum will react a certain way with this scenario, but if you're layering with samples in the mixing stage, you'll find bass frequency build ups from the decay overlapping that occurs. Be careful with this because it can quickly cause all kinds of problems.
In Rock, guitars have much less gain, this allows them to carry more melody in the chords and notes in the sound. With metalcore, you've got a variety of "riffs" that involve palm muting, tapping, and deep chugs that all need to have varying levels of bass response and gain. It is a tough balancing act to achieve clarity in this scenario so it often can call for re-amping guitars so that the tone is ultra consistent and stabilized, where I feel rock is a lot more loose. In metalcore, many guitar players use a tube screamer to help tame the differences between the bass, treble, and dynamics before going into the amp. Plus it gives you a nice amount of gain right away. Finally, Metalcore guitars require much more "wall of sound" treatment in order to balance in the heaviness and chaos of the composition where as Rock guitars will get out of the way of the singer in all the right spots. This requires you to take a careful approach when riding the faders during automation between the two genres.
The bass in rock is free to roam and perform much more playful parts, while metalcore typically calls for much more straight forward performance. That means your pitch needs to be super locked in so that the bottom end doesn't fluctuate too much against the same pitch of the other instruments. Otherwise, the tiny dissonance between the bottom end of the bass and the bottom end of the guitar will start to sound very loose very quickly. In rock, bass and guitars are often complimenting each other, and thus the temperament spread isn't as strict. This allows you to ride a little more wild on Rock, and be a little more conservative in metalcore.
Mixing Metalcore Vocals
Finally with vocals, we see the rock genre generally being melodic, even when the vocals are raspy. Metalcore adds a whole new technique known as screaming. Screaming usually requires heavy amounts of compression as the human voice has trouble controlling the dynamics with this type of techinque. There are also different types of screaming techniques, some of which require additional processing to control properly (such as the Zen of Screaming Technique). Gain Reduction Deluxe, my vocal compressor, was built specifically to handle the wild and chaotic vocal techniques we hear in modern productions today, check it out at gainreduction.com
Do you have experience mixing Metalcore?
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