This function is used to calculate Sound Check values. If Sound Check is enabled in iTunes or Music, the values will be imported whenever Yate adds the file to iTunes or saves the file when linked to iTunes. The functionality is currently not available for APE, DFF, DFS, FLAC, OGG or WV files.
The statement assumes that a ReplayGain statement has already been executed as its produced values are required.
For MPEG-4 files the produced item is stored as a UDTI named iTunNORM. For all other valid file types the item is stored as a Comment named iTunNORM.
The LUFS offset field can be used to change the parameters used to produce the value. The offset, if any is relative to the LUFS value used to produce the ReplayGain Track Gain and ReplayGain Track Peak items. While any reasonable LUFS value can be used as a baseline for loudness, it makes more sense if all your tracks are based on the same value. Yate's default LUFS value used in the ReplayGain statement is -18. This can be changed in Settings-Audio. Apple applications supposedly use -16 as their LUFS value when doing its calculations. You can leave the ReplayGain LUFS as -18 and specify an offset of 2 if you wish the Sound Check settings to be based on -16. The LUFS offset field can contain any of the escape sequences described in Escape Sequences. If the field is empty at runtime, the offset specified in Settings-Audio-General is used.
You can elect to use the track or album ReplayGain values when calculating the Sound Check data. While typically the track values are used, it is a personal preference.
You can also choose to ignore peak data. Some applications produce the Sound Check data with peak and some do not.
If an audio file does not have the required ReplayGain UDTI items, sound check will not be produced for those files.