#006 - High-Pass Every Reverb Return at 250 Hz

Reverb adds energy across the entire frequency spectrum by default - including the low end. When you've got three sends going to the same reverb return (snare, vocal, lead synth), the low-frequency reverb energy accumulates and starts competing with your kick and bass. The fix is simple, universal, and immediately makes mixes feel cleaner: high-pass the reverb return itself.

The technique

1. On your reverb return bus, insert an EQ before the reverb output (or after the reverb if your DAW doesn't allow pre-reverb EQ on a return)
2. Apply a high-pass filter at 250 Hz with a 24 dB/octave slope
3. For very busy mixes, push the cutoff up to 300-350 Hz
4. For sparse mixes where reverb can take more low-end space, drop to 180-200 Hz
5. A/B with bypass - the mix should feel cleaner in the low end without obviously losing reverb character

This works because reverb low-end is structural mud rather than perceptible reverberation. The human ear identifies reverb by the mid and high frequencies decaying over time - the low-end energy adds no perceptual reverb character but does add tonal buildup that competes with kick and bass.

The same logic applies to delay returns. High-pass delays at 200-300 Hz to keep delay tails from muddying the low end across busy DnB and dubstep arrangements.