Setting Appropriate Input Gain and Monitoring Levels

Understanding Input Gain and Monitoring Levels

Input gain controls the amount of signal that is sent from an audio device, like a microphone or an instrument, into an audio console or digital audio workstation (DAW). It boosts the incoming audio signal to a usable level.
Monitoring levels are the volume at which the audio is listened to during recording, mixing or editing.
Both need to be set correctly to ensure a clear, professional recording without distortion or noise.

Setting Appropriate Input Gain

Input gain should be set so that the peak level of the audio signal comes close to the maximum allowable without causing distortion. This is also known as ‘gain staging’.
To set gain on a mixer or audio interface, start with the gain setting at its lowest, play the sound source at its loudest, and gradually increase the gain until the peak level meter shows a level close to 0 dB.
Avoid clipping, which is when the signal exceeds the maximum level and results in distortion. If the peak level meter often goes into the red zone, the gain is too high.
It is better to have the gain setting slightly too low than too high. A signal that is too weak can be amplified later, but a distorted signal cannot be fixed.

Monitoring Levels and Headroom

Headroom is the difference between the average level of the audio signal and the highest level it reaches (the peak level). It is a buffer that protects against unexpected loud sounds causing distortion.
Monitoring levels should be comfortable for prolonged listening. If they are set too high, the risk of damaging your ears increases, and it can also lead to poor mix decisions.
Usually, the average level of a mix (the level of the signal most of the time, not the occasional peaks) should be quite a lot lower than 0 dB, leaving plenty of headroom.
The amount of headroom needed depends on the type of music and the dynamic range (the difference between the loudest and quietest parts).

Using Meters for Gain and Level Monitoring

Audio consoles and DAWs have meters to help monitor gain and levels. These might show peak level, RMS (average) level, or both.
The peak level meter shows the highest level the audio signal reaches. Use this when setting input gain to avoid clipping.
The RMS level meter shows the average level of the signal, which is useful when setting monitoring levels and adjusting the balance between different tracks in a mix.
Some meters use a colour scheme to indicate different levels: green for safe, yellow for caution, and red for danger.

Importance of Correct Gain and Level Setting

Correct gain and level setting is key to producing high-quality, professional-sounding recordings.
Too high input gain can cause distortion, which sounds unpleasant and cannot be fixed later.
Too low input gain can lead to noise, as the signal might need to be amplified a lot later, which also amplifies any background noise.
The right monitoring level helps you to make good decisions when balancing different parts of a mix and applying effects.

To set up a clean, optimal recording, you’ll need to understand and correctly manage your input gain and monitoring levels. Mistakes in this area can lead to poor quality recordings that are difficult to post-process efficiently.