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MIX AUDITING

A/B Loudness Matching & Mix Comparison

How to compare two mix revisions objectively by matching their integrated LUFS levels and eliminating volume bias.

Why Volume Bias Fools Mixing Engineers

Every audio engineer knows the oldest trick in the book: louder sounds better. When comparing two mix revisions where Mix B is just 0.8 dB louder than Mix A, your brain will almost always trick you into thinking Mix B has better bass and clearer vocals, even if you actually made a bad compression choice.

Sabes Pro includes a built-in EBU R128 / ITU-R BS.1770 LUFS Loudness Matcher that levels the playing field completely.

Where to Find A/B Compare in the App

You can access the comparison tool in two easy ways:

  • From the Top Bar: Click the A/B Compare tab located at the top of the Sabes Pro desktop window.
  • From the Take Timeline: Hold Ctrl to select any two Takes on your timeline, and click Compare A/B in the action bar.

Step-by-Step: Comparing Two Mix Bounces

  1. Open the A/B Compare screen. You will see two audio slots: Slot A and Slot B.
  2. Drag and drop your audio files (WAV, FLAC, or MP3) directly into each slot, or choose rendered audio bounces from your tracked Takes.
  3. Click the blue button: Match Loudness.
  4. Sabes Pro analyzes both audio streams in real-time, calculating:
    • Integrated LUFS: The true perceived loudness of both tracks.
    • Loudness Difference (LU): The exact gain offset needed to balance them.
    • True Peak (dBTP): The inter-sample peak level to detect digital clipping.
  5. Click Play. Use the [A] and [B] toggle buttons (or press A and B on your keyboard) to switch back and forth instantly while the music is playing.

What to Listen For During Blind A/B Auditing

With volume bias removed, you can make true, confident mixing choices:

  • Vocal Sit & Balance: Does the vocal sit comfortably on top of the snare and bass, or is it buried?
  • Low-End Mud vs. Tightness: Did your multiband compression actually clean up the 200 Hz region, or did it just thin out the track?
  • Transient Punch: Did your master bus limiter crush the snare transient snap?

Next Steps

Ready to deliver your final master? Learn how to generate a cryptographic delivery certificate in our Take Certification Guide.