Gain is used for signal level adjustment at the input point of a device or software. At this point, the signal has not yet undergone any processing. Volume is used for signal level adjustment at the output point of the device or software. In other words, volume controls the level of the signal that has been processed and arrived at the output point.
For example, you plug a microphone into one channel of the mixer. The gain setting controls the level at the entry point. As the next step, let's assume that you pass the signal through the compressor via the insert point.
Then, this signal processed with the compressor comes to the fader in the channel. The fader acts as a volume control here. When you adjust the level with the fader, you are adjusting the level of the processed signal. To put it simply and explain: Gain is the signal level at the entry point; volume controls the signal level at the output point.
Gain means three things:
- Another word for volume or how loud the output is
- How loud is the entrance
As you mix, you'll likely find that all three are used.
The difference between gain and volume is important because the gain setting affects the operation of the signal processors you use at the insertion point.
As an example, let's assume that there is a compressor at the insertion point. When you increase or decrease the gain level (because the gain setting is before the insert point), the level of the signal to the compressor changes. Accordingly, the response of the compressor to the signal also changes.
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