In the world of music, you encounter decibels (dB) all the time - whether at the mixing console, in your DAW, or when buying speakers. But why are dB so important in the world of music?
1. 0 dB does not equal silence
In music, it all depends on the reference point. In the music studio (digital): Here, 0 dBFS (full scale) is the absolute upper limit. Anything above this will “clip” and distort badly. Your level meters in your DAW (Ableton, Logic, etc.) will therefore usually show negative values such as -6 dB or -12 dB.
In the rehearsal room (acoustics): Here, dB SPL (Sound Pressure Level) is used. 0 dB is the hearing threshold; a rock concert is around 120 dB.
2. The “fader logic”: Why +6 dB and not +3 dB?
In your DAW or on the mixing console, you work with voltage/amplitude, not pure power. Therefore, in contrast to the usual dB rules, values other than doubling apply here:
+6 dB on the fader: This doubles the amplitude (the deflection of the waveform). Technically speaking, the signal becomes twice as strong.
+10 dB on the fader: Only then is it perceived by the human ear as double the volume.
+3 dB: This happens when you mix two identical signals (e.g., two guitar tracks with the same volume) that are notperfectly in phase. If they are exactly the same (phase coherence), the level actually jumps by +6 dB.
3. What does this mean for a mix?
Headroom: If you make a track 3 dB quieter, it's a subtle nuance. If you lower it by 10 dB, you “halve” its perceived presence in the mix.
The 85 dB secret: Many professionals mix at around 83–85 dB SPL in the room. Why? In this range, the human ear hears frequencies (bass and treble) most linearly (known as Fletcher-Munson curves). If you mix too quietly, you often turn up too much bass; if you mix too loudly, your ears tire immediately.
Tip: If you “double” two identical vocals to make them sound fatter, your master level will increase by about 3 to 6 dB. Keep this in mind to avoid clipping!