Metadata, ID3v2 and VORBIS tag transparency

Stereo Lab custom metadata is inserted into audio files as audio conversions are performed. This tags useful information such as the enhancement and post-process that were applied, and the date and time of the conversion. A warning is issued in the table view if you subsequently attempt to convert any file which was previously processed by Stereo Lab. This is indicated by turning the line comments in the conversion table orange.

A pop-up window is also invoked unless it is disabled in the Settings dialogue.

Because Stereo Lab implements correction/enhancement processes which may not be appropriately cascaded, the software includes the addition of the appropriate metadata in the file header each time a file is processed and a warning is issued in the GUI if two conversions are cascaded

ID3v2 tags

The ID3v2 tag was popularised by the MP3 audio file format because it allows information such as the title, artist, album, track number, artwork, and other information about the file to be stored in the file itself.

Pre-existing ID3v2 metadata is retained during all conversions of AIFF, AIFF-C, WAV and FLAC files, even when converting between different file types. This metadata is not modified in any way by Stereo Lab.

Stereo Lab supports ID3v2 metadata transparency during all conversions of AIFF, AIFF-C, WAV and FLAC files. The metadata is not modified in any way by the software, so that you will not loose precious artwork, track-listings etc. when processing files with Stereo Lab


FLAC files also store track information in VORBIS comments and track artwork in PICTURE blocks. Any such pre-existing FLAC metadata is always retained by Stereo Lab during audio conversions between FLAC files. This means that FLAC files can contain VORBIS/PICTURE tags and ID3 tags at the same time, but there is no conversion between them.

The FLAC standard only guarantees that VORBIS comments will be read by any flac compliant program, while ID3 may be read by some but not by others. Note that VORBIS comments and PICTURE blocks are never stored inside the metadata of AIFF, AIFF-C or WAV files

Broadcast Wave format

When the option to include Broadcast Wave Format (BWF) metadata in WAV files is enabled, 'Broadcast Audio Extension' (BEXT) information is created/updated with the EBU R128 loudness values. Any pre-existing 'Location Sound' (iXML) metadata will also persist unchanged during audio conversions.

You can view various audio metrics of files by right-clicking on them in the Stereo Lab table view, selecting Copy Audio Metrics to Clipboard, and then pasting the text into an text editor application such as TextEdit. The amount of information that you get to see depends on the metadata contained within the source audio file, and whether the file is yet to be converted or not.

When Broadcast Wave Format (BWF) metadata in WAV files is enabled, Broadcast Audio Extension information is created or updated with the EBU R128 loudness values calculated by Stereo Lab


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