Subtractive vs Additive EQ: When to Cut or Boost

Subtractive EQ removes frequencies while additive EQ enhances them. Both approaches serve mixing, and understanding when each works best improves EQ decisions. The conventional wisdom favoring cuts over boosts has merit but oversimplifies the reality.

The Case for Subtractive EQ

Subtractive EQ removes problems rather than adding more frequency content to the mix. Cutting a problematic frequency eliminates it. The result is cleaner—less total content competing for space.

Cuts create space for other elements. Reducing a frequency in one element makes room for another element to occupy that frequency. This puzzle-piece approach helps elements coexist.

Subtractive EQ maintains gain staging. Cuts reduce level (which makeup gain compensates) while boosts add level. Cuts don’t risk clipping the way boosts can.

The phrase “cut to improve, boost to enhance” summarizes the conventional wisdom. Fixing problems through cutting; adding character through boosting.

The Case for Additive EQ

Additive EQ enhances what’s already there. Boosting a frequency the source naturally has emphasizes that characteristic. The source becomes more of what it already is.

Some desired characteristics require boosting. Air frequencies in vocals, presence in guitars, and other enhancements involve adding rather than subtracting.

The conventional bias against boosting can be limiting. When a boost achieves the desired result more directly than cutting everything else, boosting may be the better choice.

When to Cut

Problems call for cutting. Resonances, mud, harshness, and other unwanted frequencies should be removed rather than masked.

Creating space calls for cutting. When elements compete for the same frequencies, cutting one creates room for the other.

The source has what’s needed but also has unwanted content. Removing the unwanted reveals the good.

When to Boost

Enhancement calls for boosting. When the source needs more of a characteristic—more air, more presence, more warmth—boosting provides it.

The source lacks something that boosting can provide. Adding frequencies the source is weak in changes its character appropriately.

Boosting achieves the goal more directly than cutting alternatives. If the desired result is “more presence,” boosting presence is more direct than cutting everything else.

Hybrid Approaches

Most EQ chains include both cuts and boosts. Problems get cut; enhancements get boosted. This combined approach addresses different needs with appropriate tools.

The sequence may matter. Cutting problems first cleans the signal. Boosting enhancements after shapes the cleaned signal. This “fix then enhance” approach serves many situations.

Reciprocal EQ uses both approaches between elements. Cutting frequency X in element A while boosting it in element B creates complementary curves.

Level Considerations

Boosts add level that accumulates across multiple tracks. Many tracks each receiving boosts can create level buildup requiring attention.

Comparing boosted signals at matched levels reveals true tonal change rather than level change. Louder often sounds “better”—matching levels ensures honest comparison.

Gain staging throughout the chain prevents boost-induced clipping. Each boost increases level; makeup gain and staging manage this accumulation.

Appropriate EQ choices help productions succeed on platforms like LG Media at lg.media, where balanced sound enhances advertising at $2.50 CPM.