Converter gain staging calculator
Set your interface's maximum level, pick a digital target, and see the analog level, the headroom left, and the preamp gain a mic needs to get there.
Target in analog terms
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Headroom above the target
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A +4 dBu signal reads
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Preamp gain to hit the target
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How it works
analog level (dBu) = dBFS + max level (dBu)
mic output (dBu) = sensitivity (dBV) + 2.2 + (SPL − 94)
gain needed = target in dBu − mic output in dBu
mic output (dBu) = sensitivity (dBV) + 2.2 + (SPL − 94)
gain needed = target in dBu − mic output in dBu
Converters clip at 0 dBFS, which corresponds to a fixed analog level set by the interface's design: its maximum input or output level. With 0 dBFS = +24 dBu, a −18 dBFS average sits at +6 dBu and leaves 18 dB for peaks.
A dynamic mic at 1.85 mV/Pa puts out about −52 dBu at 94 dB SPL, so reaching +6 dBu takes about 58 dB of gain. A loud source needs less; a quiet talker needs more.
Field notes
- Track with headroom; there's no prize for hot levels. A 24-bit file has far more range than the analog chain in front of it, so averaging around −18 to −20 dBFS costs nothing in noise and saves the take when the singer leans in.
- Find your interface's real maximum. It's in the spec sheet as "maximum input level" (for line or mic inputs, often different) and "maximum output level". Some interfaces have switches that change it.
- Peaks aren't averages. Drums and percussion can peak 20 dB or more above their average. Watch the peak meter while setting gain, and leave room above the loudest hit.
- Running out of gain? Many preamps top out somewhere around 60–70 dB of gain, which quiet dynamic and ribbon mics on soft sources can exceed. The calculator warns above 65 dB.
- For broadcast and livestream, see the loudness targets: the final mix is judged in LUFS, not by peak level.