High-Pass Philosophy: Clearing the Mix Mud
The "Mud" Problem
Low frequencies carry the most energy in a mix. If your acoustic guitar, vocal, snare, and synth pad all have energy at 100Hz, they will sum together to create "mud." The High-Pass Filter (HPF) is your primary weapon for carving out space.
When to Cut (and When NOT to)
A common beginner mistake is to "high-pass everything." This leads to thin, sterile mixes. Follow this philosophy:
- Safe Cleaning: Almost every channel (except Kick and Sub) can handle a cut at 30-40Hz. This removes imperceptible rumble that eats up headroom.
- Contextual Cleaning: If a guitar is playing alone, let the low end breathe (80Hz). If it's in a dense rock mix, cut deeply (up to 200Hz) to let the bass guitar own that space.
🎧 The Slope Matters
Most EQs default to a 12dB/octave slope. This is gentle and musical.
For cleaning up a sub-bass or kick, try a steeper 24dB or 48dB slope.
This cuts the unwanted frequencies vertically, tightening the low end instantly.
Advanced: Dynamic High-Pass
Sometimes a static EQ cut removes too much "body" when the singer goes low. In 2026, use a Dynamic EQ (like Pro-Q 3). Set the high-pass band to only engage when the low frequencies exceed a threshold. This keeps the warmth during quiet sections but cleans up the mud during loud passages.