Mixing from 9B to 3B

How to mix this transition

Execute this move at a phrase boundary—ideally a 16 or 32-bar breakdown where the outgoing track has stripped to minimal elements (drums only, or a single melodic hook). Bring in the new track's kick and bass locked to the beat, then layer in harmonic content over 4–8 bars to let the tritone interval register without feeling chaotic. Use a high-pass filter kill on the outgoing track's top end in the final 4 bars to create sonic space; avoid EQ-blending the two harmonic layers simultaneously, as the tritone will muddy. The shock lands hardest when the new track's first melodic or harmonic phrase enters cleanly after the kick swap—don't bury it under the old track's reverb tail.