This is an article by FearComplexMusic
1. Only Quad Track (4 individual performances, 2 panned left, 2 right) if you’re tight. Anything other than tight as nails tracking can and will lead to a weird phasey hollow sound. Also, I find dual tracking (with more gain per track) works better for the super fast technical stuff, quad (with less gain per track) for the slower heavier chunky palm mute material.
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