Vocabulary Clarification: Volume, Loudness, Level, Gain, and Amplification

You’ll find that in the world of music production, there are a few words that either mean the same thing, mean similar things, or are incorrectly used interchangeably. Before I start explaining plug-ins and how to use them, I want to clear up some of this terminology so that I don’t have to repeat myself or explain these terms as I go.

Though they all mean quite different things, the terms I’ll be clarifying this week all have something to do with amplitude, which you can think of as the “intensity” of a sound, or how loud or soft it is.

Volume is a word that is used to mean all sorts of things, but technically it refers to the amount of power used to amplify a signal. Volume usually describes an output signal.

Loudness, often used interchangeably with “volume,” refers simply to the perceived intensity of a sound by the human ear. Loudness varies by frequency, but we won't get into the physics of it here.

Level is used to describe the amplitude of a sound in reference to some arbitrary value. We use SPL (sound pressure level) to measure the level of a sound in decibels (dB).

Gain refers to the amount by which a signal’s amplitude is increased or decreased in the process of amplification. These two terms are practically interchangeable, but “gain” usually refers to the change in amplitude, measured in dB, while “amplification” is used more generally to refer to the process as a whole. “Gain” and “amplification” are used to describe an input signal.

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These five terms are all descriptive of the "quantity" of sound. Next week I'll clarify five more terms that describe the "quality" of sound.