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MIX AUDITING

A/B Loudness Matching & Mix Auditing

How to audit mix revisions objectively by matching LUFS integrated levels and eliminating volume bias.

Sabes Pro A/B Loudness Matching Screen

The Perceptual Loudness Bias

In music production, the human brain perceives louder audio as sounding automatically clearer or punchier. When comparing two mix revisions where Mix B is 1 dB louder than Mix A, you will prefer Mix B regardless of whether your EQ or compression tweaks were actually improvements.

Sabes Pro resolves this using EBU R128 Loudness Matching.

How A/B Loudness Matching Works

Sabes Pro measures integrated LUFS (Loudness Units Full Scale), Dynamic Range (LRA), and True Peak values across rendered Take bounces. When comparing Take A and Take B, Sabes Pro applies an automated gain offset to match perceived loudness during auditioning.

Step-by-Step Auditing Guide

1. Select Two Take Nodes

On your Take Reel timeline, select your baseline Take (e.g. Mix_Pass_01) and hold Shift to select a second Take (e.g. Mix_Pass_02).

2. Launch A/B Comparison

Click Compare A/B Loudness in the action bar. Sabes Pro analyzes the audio bounces linked to both Takes.

3. Review EBU R128 Metrics

The A/B Inspection panel displays side-by-side metrics:

  • Integrated LUFS: Long-term loudness measurement across the file.
  • Loudness Range (LRA): Dynamic range measurement in LU.
  • Max True Peak: Peak signal level in dBTP to check for digital clipping.
  • Gain Offset Applied: Automated dB adjustment applied to match playback levels.

4. Perform Blind A/B Auditing

Use keyboard shortcuts (Key A / Key B) to switch between both Takes during playback. Because levels are gain-matched, you can evaluate EQ balance, vocal levelling, and compression settings based on sound quality rather than volume differences.