What is RMS volume?

RMS, or root mean square, is a practical way to determine the average level of the signal, and it’s close to how our ears perceive loudness.1

RMS is the square root of the mean square.2 The mean square is the mean of the squares of a set of numbers.3 RMS squares the values, averages those values over a period of time, then finds the square root of that.4

Why RMS? Simply averaging the values would not be helpful, since most signals vary between positive and negative, making the average usually around zero.5

RMS is also known as the quadratic mean in arithmetic.5

  1. Gain Staging Like a Pro ↩

  2. What is “RMS (Root Mean Square)”? ↩

  3. Mean square - Wikipedia ↩

  4. Audio Production and Critical Listening pg. 79 ↩

  5. Root mean square - Wikipedia ↩ ↩2

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