Equal-Power Crossfade Gain Calculator

Method, formula and assumptions

A gain = cos(position x pi/2), B gain = sin(position x pi/2), with position from 0 to 1. Uncorrelated RMS is the square root of the summed squared weighted RMS values.

Input definitions and supported units

• Crossfade position (% toward B): Measured or assumed numerical value, from 0 to 100; zero is supported where the stated method permits it.
• Source A RMS amplitude: Measured or assumed numerical value, from 0 to 10; zero is supported where the stated method permits it.
• Source B RMS amplitude: Measured or assumed numerical value, from 0 to 10; zero is supported where the stated method permits it.

Worked example with answer

At 50% with two unit-RMS inputs, both gains are 0.7071. Uncorrelated output RMS is 1; fully correlated in-phase amplitude is 1.4142.

How to use the results

The correlated comparison explains why a mathematically equal-power fade can still swell with nearly identical material. The input amplitudes need not be equal.

Results retain full precision internally and display up to four decimal places. Very small nonzero results use scientific notation rather than appearing as zero. Check the labels before comparing values across units.

Limitations and references

Correlation is idealized at two extremes. Actual audio can change phase and correlation across frequency and time, and these RMS figures do not predict peaks.

The method is a self-contained arithmetic, geometric or explicitly stated mathematical model. There are no imported tariffs, empirical presets or equipment specifications; measured values and allowances must come from your own process.

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