Analog VU (volume unit) meters are a type of mechanical device that measures and displays the average level of audio signals. They are called "analog" because they use mechanical movement to display the level of the audio signal, as opposed to digital meters which use numerical values to represent the level.
Analog VU meters typically consist of a needle or pointer that moves across a calibrated scale, with markings for different levels of audio. The needle or pointer will move in response to the audio signal, indicating the average level of the signal.
One of the main uses of an analog VU meter is to ensure that audio recordings are at the proper level and that they don't peak or fall below a certain threshold. This can help to prevent distortion and ensure that the audio is clear and of high quality. Additionally, VU meters can be used to ensure that the audio levels are consistent across different tracks and recordings, which can help to make the final mix sound more cohesive.
Another use of VU meters is for monitoring audio levels during live performances. This can help to prevent distortion and ensure that the audio is at the appropriate level for the audience.
VU meters are designed to respond to audio signals in a way that mimics human hearing, taking into account the way our ears perceive loudness and volume. This means that a VU meter will respond differently to different types of audio, such as speech and music, and will indicate the appropriate level for each.
In summary, analog VU meters are a type of mechanical device that measures and displays the average level of audio signals. They are used to ensure that audio recordings are at the proper level, prevent distortion, ensure consistency across different tracks and recordings, monitor audio levels during live performances and respond to audio signals in a way that mimics human hearing.
It's important to note that, while analog VU meters can be a valuable tool for audio engineers and music producers, it is just one tool in the arsenal. They are not as accurate as digital meters, and should be used in conjunction with other tools and techniques, such as EQ, compression, and listening to the audio on different playback systems to achieve the best results.