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What is ISRC and Red Book Standard?

Questions concept

Sage Audio is a mastering studio that follows the guidelines of the Red Book and offers services to add ISRC encoding to recordings. Most amateurs mastering their own music are usually not too familiar with all of the requirements of the Red Book which could cause some problems when duplicating CD's for mass distribution. There is also often a lot of confusion about what exactly ISRC is, how to acquire these codes, and whether or not they are necessary.

Red Book is the audio standard for compact discs that ensures that all of the music following these guidelines will play in the majority of CD players. It got its name from a series of books called Rainbow Books and as the name states, is the red colored book that focuses on CD- Digital Audio. The Red Book consists of technical specifications for CD and CD-ROM and includes some of these basic guidelines:

  • Maximum duration is 74 minutes
  • Each track must be a minimum of 4 seconds
  • Maximum of 99 tracks
  • 99 maximum number of index points
  • ISRC encoding

There are some other areas that define bit rate and error correction, but are usually of no concern when sent into a studio that is associated with mastering audio.

This leads us to the next subject of a lot of confusion. ISRC is the International Standard Recording Code for identifying sound recordings. These codes are registration information that is added to a CD as an individualized and permanent identifier of the track. Only one ISRC code can be added to an individual track and can never represent more than one recording. For example, a different recording or remix of the same song requires a different ISRC code. These numbers are useful in tracking commission and royalty payments for songs.

It is only a one-time payment of $75 through which allows users to assign up 100,000 ISRCs annually. The ISRC consists of 4 parts and is 12 characters long:

  • Country Code
  • Registrant Code
  • Year of Reference
  • Designation Code

The country code for the US has actually been changed to QM as of 2010. The three character registrant code is assigned by the National ISRC agency. The two year of reference digits refer to the year that the track was registered; not when it was recorded. The final designation code is intended to be a unique individual code for each track. It is recommended to start your track codes as 00001, 0002, 0003, and so on. This helps ensure that no codes are repeated and helps keep your tracks in order for your own filing system. During the next year of registering songs you can start the designation codes back at 1 since the year of the code will be different.

Example of a new ISRC- QM-364-12-00001

After obtaining your ISRCs, you are ready to have them added to your CD's through various mastering studios such as Sage Audio.