In sound engineering we useÂ different kinds of meters that visually gives us the different measurements of sound.
The first and the most known is the level meters. Simple as it sounds, it gives us the visual of the level of our sound source. These are measured in DBFS (Decibel before full scale) where 0 DB is theÂ maximum amplitude. Above 0 clipping will occur.
Level meters will also usually display Peak level and RMS (Root means square) level.
The peak level is the highest voltageÂ of a waveform, its peak. ThisÂ is an important tool to show how much “headroom” we have. This gives us the understanding of how much we can boost our signal before clipping or distort the signal. RMS level is the average level and is a level that is relating more to the psychoacoustic of the human hearing. Important to mention is that the RMS level is not takingÂ account of howÂ the human ears perceve the loudness of the different frequencies. For example 3oo hzÂ can be percieved as lower than the same amplitud of 4000hz.
Spectograms visualize the amount of energy moving across the sound sprectrum. This means that you can actually see how much Â energy a specific frequency area has even if you cant hear it. This is a powerful tool to see if there is too much of something. Most often the base.
Stereo meters gives us information about the how theÂ stereo signal is. A vectorscope is a tool that shows if something in the sound is out of phase.
A stereo image meter is a sort of vectorscope that shows how much of the information is centered. Recordings should have its source in the centre even if it is widened. If you listen to your recording in mono you wouldnt want important elements to be diminished or even disappear. This could happen if too many elements is out of phase.
A correlation meter will show whereÂ the stereo image of the sound picture is.