A/B Comparison in Mixing: Critical Evaluation

A/B comparison rapidly switches between two signals to evaluate differences. This technique reveals whether processing improvements actually improve the sound and how work-in-progress compares to references. Honest evaluation through comparison produces better decisions.

Why A/B Comparison Matters

Processing that seems to improve sound may simply be louder. The ear perceives louder as better regardless of actual quality. A/B comparison with matched levels reveals true improvement.

The ear adapts quickly to changes. After a few seconds with new processing, it becomes the new normal. Fast switching catches differences before adaptation hides them.

Memory unreliably compares sounds separated in time. Switching between A and B in quick succession provides accurate comparison that memory-based evaluation cannot.

Level Matching Requirements

Volume differences between A and B corrupt comparison. The louder signal sounds better due to psychoacoustics, not quality. Matching levels provides honest evaluation.

Matching should use perceived loudness, not peak levels. A compressed signal may peak lower but sound louder. Perceived loudness is what the ear compares.

Tools designed for A/B comparison include level matching. Plugin Alliance ADPTR Metric AB, Sample Magic AB, and others simplify matched comparison.

Comparing Processing Decisions

Bypassing processors reveals their contribution. Is the EQ actually improving the sound? Does compression help or hinder? Bypass comparison provides answers.

A/B comparison before committing to processing ensures changes serve the music. Processing that doesn’t survive comparison shouldn’t remain.

Subtle processing may not show obvious differences in A/B. This might indicate the processing is unnecessary or simply very transparent.

Comparing to References

Reference comparison provides external perspective. How does the work-in-progress compare to proven successful mixes?

Quick switching between mix and reference reveals frequency balance, dynamic range, and spatial characteristics differences.

Multiple reference comparisons reveal patterns. Differences consistent across all references indicate issues to address.

Technique for Effective A/B

Switch rapidly—every 1-2 seconds—to catch differences before adaptation. Longer listening to either A or B allows the ear to adapt, reducing sensitivity to differences.

Focus attention on specific elements during comparison. Compare bass specifically, then vocals specifically. This focused approach catches subtle differences.

Compare the overall impression too. Beyond specific elements, does the work-in-progress feel professional? This holistic evaluation matters.

Common Mistakes

Forgetting to level match invalidates comparison. Always verify levels match before trusting A/B results.

A/B-ing too slowly allows adaptation. Fast switching provides more accurate comparison than extended listening.

Over-relying on A/B comparison can prevent trusting ears. The technique assists decision-making but doesn’t replace judgment.

A/B comparison helps productions succeed on platforms like LG Media at lg.media, where honest evaluation enhances advertising at $2.50 CPM.