How do you use LUFS and LKFS to measure and adjust loudness in audio mastering?

1 What are LUFS and LKFS?

LUFS stands for Loudness Units Full Scale, and LKFS stands for Loudness, K-weighted, relative to Full Scale. They are both units of measurement that express the average loudness of an audio signal over time, using a logarithmic scale that mimics the human hearing response. The higher the LUFS or LKFS value, the louder the audio. The difference between them is that LUFS is used in Europe, while LKFS is used in the US and other regions. However, they are essentially the same thing, and you can interchange them without affecting the results.

3 How do you measure loudness with LUFS and LKFS?

To measure loudness with LUFS and LKFS, you need a loudness meter plugin that can analyze your audio and display the values in real time or offline. There are many loudness meter plugins available, such as Youlean Loudness Meter, iZotope Insight, or Waves WLM Plus. A loudness meter plugin typically shows you three values: integrated, short-term, and momentary. Integrated LUFS or LKFS is the average loudness of your entire track or program, and it is the most important value for loudness normalization. Short-term LUFS or LKFS is the average loudness of the last 3 seconds of your audio, and it reflects the dynamic changes and peaks. Momentary LUFS or LKFS is the average loudness of the last 400 milliseconds of your audio, and it captures the instantaneous loudness.

4 How do you adjust loudness with LUFS and LKFS?

To adjust loudness with LUFS and LKFS, you need to know your target loudness level, which depends on your intended platform, genre, and style. For example, Spotify uses -14 LUFS as its target loudness level for streaming, while YouTube uses -13 LUFS. Other platforms may have different standards, so you need to do some research before mastering your audio. Once you know your target loudness level, you can use a gain plugin or a limiter plugin to increase or decrease the overall volume of your audio until it matches the target integrated LUFS or LKFS value. You can also use a compressor plugin or a dynamic EQ plugin to reduce the dynamic range of your audio if it is too high or too low.

5 What are the benefits of using LUFS and LKFS?

Using LUFS and LKFS for loudness measurement and normalization has many benefits for audio mastering. First, it helps you achieve a consistent and professional sound quality across different platforms and devices, and avoid unwanted distortion, clipping, or noise. Second, it helps you preserve the natural dynamics and transients of your audio, and avoid over-compression or over-limiting. Third, it helps you comply with the industry standards and regulations for broadcast, streaming, and distribution. Fourth, it helps you improve the listener's satisfaction and engagement with your audio, and avoid loudness wars or fatigue.