How to keep background music at a set percentage of the conversation
Tell Vizard Agent the percentage you want, such as 15% of the voices. It turns that number into decibels, measures the voices moment by moment and lowers the music wherever it would come closer than that, so the rule holds under the quietest speaker too, not just on average. It never raises the music anywhere.
What do you type into Vizard Agent?
A percentage is a good way to ask, as long as you say what it is a percentage of. Saying the conversation, not the whole video, tells Vizard Agent to keep the music below the voices at every moment, including when someone speaks softly or turns away from the microphone.
Turn the added music down so its volume stays at about 15% of the conversation.
What does Vizard Agent actually do?
It converts the number first, because 15% of a level is about 16.5 dB below it, and checks the moments rather than the average. An average can pass while the quieter speaker's lines still sit too close to the music. In the session behind this article it:
- Measured the voice and music tracks separately. On average the music was already about 19 dB under the voices, but under the quieter speaker it came within about 13 dB, roughly 21%.
- Set a target of 18 dB under the voices, about 12.6%, to stay safely below the requested 15%.
- Built a gain curve from the voices' loudness every tenth of a second. It ducks slightly ahead of quiet lines, releases slowly, never raises the music, and holds it lower through a wordless pause.
- Applied the curve to the music alone and remixed it with the untouched voice track, copying the picture as it was.
- Checked the quieter speaker's 7.6-second stretch afterwards: voice at −20.9 LUFS, music at −39.5, 18.6 dB apart.
When does this not work well?
When the voices are very quiet everywhere. Keeping the music 18 dB under a whisper leaves it barely audible, and a bed that keeps ducking can start to sound like it is pumping. Then raising the voices first, or choosing calmer music, works better than a stricter curve.
Common questions
What does 15% mean in decibels? About 16.5 dB quieter. Vizard Agent aims a little below.
Why isn't the average enough? Quiet speakers dip. Vizard Agent checks moment by moment.
Will the music jump up and down? No. Vizard Agent releases slowly and never raises it.