Gain staging is the discipline of setting the right signal level at every point in a mix chain so the signal stays clean from input to output. Set a stage too low and later boosts amplify hiss; set it too high and the signal clips. This calculator lets you build a chain of stages — preamp, EQ, compressor makeup, fader, and anything else — and watch the running level, the headroom below clipping, and the signal-to-noise above the floor at each point.
How it works
Levels are tracked in dBu. Because decibels are logarithmic, the gain of each stage simply adds to the running level rather than multiplying:
level_out = level_in + gain
At every stage the calculator derives two diagnostics from the running level:
headroom = ceiling − level (dB of room left before clipping)
SNR = level − noise floor (dB the signal sits above the noise)
It assumes a clip ceiling of +24 dBu and a noise floor of −90 dBu, with nominal 0 VU at +4 dBu. A stage above the ceiling is flagged CLIP; one with under 6 dB of headroom is flagged hot; one whose SNR falls under 40 dB is flagged noisy.
Example
Starting from a −40 dBu microphone signal through a 40 dB preamp, flat EQ, −6 dB of compressor makeup, and a unity fader:
- After preamp: −40 + 40 = 0 dBu (24 dB headroom, 90 dB SNR)
- After EQ: 0 + 0 = 0 dBu
- After compressor: 0 − 6 = −6 dBu
- After fader: −6 dBu at the bus
Every stage sits comfortably below the ceiling and far above the floor — a clean chain. If instead the preamp were set to 70 dB, the level would hit +30 dBu and the stage would clip.
Tips
Do most of your gain early: set the preamp so the signal is strong and clean, then use EQ and dynamics to shape rather than to rescue level. Keep the average near nominal with 12–18 dB of headroom so transients never clip. If you find yourself boosting a fader far above unity to hear a channel, go back and raise the preamp instead — that is where the gain belongs. All processing runs locally in your browser.