Mastering A/B testing

When you are A/B testing with Gain Match ON, you aren’t listening for volume. You are listening for texture, space, and impact. It’s easy to get distracted by the “shiny” new sound, but a professional master should enhance your mix, not change its soul.

Here is exactly what to listen for in each frequency range:

1. The “Low End” (Kick and Bass)

• The Goal: The bass should feel tighter and more focused, not necessarily “bigger.”

• What to listen for: Does the kick drum still have its “thump,” or did the AI turn it into a soft “thud”? If the bass feels like it’s “breathing” or “pumping” (turning down every time the kick hits), your Intensity setting is likely too high, or your mix has too much sub-bass.

2. The “Mid Range” (Vocals and Snare)

• The Goal: Clarity and presence.

• What to listen for: Does the vocal feel like it’s sitting “on top” of the music, or did it get pushed back into the mix? AI mastering often uses “mid-side” processing; if the vocals start to sound thin or hollow, the AI might be trying too hard to widen the track.

3. The “High End” (Cymbals and Air)

• The Goal: “Expensive” sounding shimmer without harshness.

• What to listen for: Focus on your “S” sounds in vocals (sibilance) and your hi-hats. If they make your ears wince or sound “crunchy,” the AI is over-emphasizing the highs. You might need to go back to your mix and use a De-esser or a High-Shelf EQ to tame those frequencies before the AI sees them.

4. The “Stereo Image” (Width)

• The Goal: A wide, immersive soundstage.

• What to listen for: Switch the plugin on and off and notice the “sides.” The master should feel wider and more “3D.” However, if the center of the mix (the snare and lead vocal) feels like it’s losing its power or “ghosting,” the width is being pushed too far.

The “Squish” Test (Dynamics)

This is the most critical part of A/B testing.

• Listen to the Snare: In a good master, the snare should still “crack” through the mix.

• The Red Flag: If the snare feels like it’s being “sucked into” the rest of the music every time it hits, the AI limiter is working too hard.

Summary Checklist for A/B Testing: | Listen For | Good Sign | Bad Sign | | :— | :— | :— | | Transients | Snare and Kick stay sharp. | Drums sound flat or “tucked in.” | | Clarity | You can hear the lyrics better. | The mix sounds “cluttered” or noisy. | | Depth | The song feels like it has “front to back” space. | The song feels like a flat wall of sound. |

Pro Tip: Listen to your A/B test at a low volume. If a master sounds good when it’s quiet, it will sound incredible when it’s loud. If it only sounds good when it’s cranked, the AI might be masking mix issues with artificial brightness.