Mid-Side Matrix Level Calculator

Method, formula and assumptions

Use M = (L + R)/2 and S = (L - R)/2. Decode with L' = M + sideGain x S and R' = M - sideGain x S. The decoded mono average stays M.

Input definitions and supported units

• Left normalized sample: Measured or assumed numerical value, from -1 to 1; signed values are supported.
• Right normalized sample: Measured or assumed numerical value, from -1 to 1; signed values are supported.
• Side gain: Measured or assumed numerical value, from 0 to 10; zero is supported where the stated method permits it.

Worked example with answer

L = 0.8 and R = 0.4 give M = 0.6 and S = 0.2. With side gain 2, decoded L' = 1 and R' = 0.2; their mono average remains 0.6.

How to use the results

This is a sample-level matrix demonstration, not a loudness measurement. Decoded magnitudes above 1 identify possible fixed-point clipping before gain compensation.

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

Do not infer stereo loudness, phase correlation or perceived width from a single sample. The normalization convention must match both encoding and decoding.

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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