An easy way to check a master audio CD for CD text, IRSC and MCN or barcode information
After many weeks, months, possibly years, working in the studio to make your album sound just perfect, the most daunting aspects of having your album manufactured can be when it’s time to hand over the master for replication or duplication.
Are all the songs present? And in the right order? Are silences between the tracks correct? Have I definitely used my final mastered song versions for the master CD?
Your mind can be put at ease easily, by having a listen back to the CD to confirm all is well.
Apart from the audio, there is also data on a disc that cannot be listened to, and one just usually hopes it is present on the final CDs that are made. This information is known as the meta-data. Meta-data can include such items as CD-text, ISRC codes, and MCN or barcode number.
Very few programs allow you to enter all of this information, and mostly found only on high-end studio software. There are even fewer programs that can read this data to verify its correctness. Some of these programs that do read the meta-data, cannot always be relied on to be accurate.
An over looked aspect of OSX, and a feature only available on MAC, (sorry PC users), is the terminal window, coupled with the powerful tools it affords. There are various commands that can be run through the terminal window, and below we are going to look at two of these that pertain to a master audio CD disc.
You can fire up terminal by going to your applications folder > utilities > terminal.
This will open a small window with a prompt to enter text. We will be using something called Drive Utilities which offers very powerful analysis text commands to check a variety of information.
When checking audio masters for meta-data the two most useful commands are CDText and subchannel.
So, ensuring the master audio disc has been correctly inserted into the drive, we type 'DRUTIL CDTEXT' and press enter. This will show us quite quickly all the meta data on the disc, we can see an example of this in Fig.2 on the right.
A deeper analysis of the ISRC codes can be acheived, by using the command, 'DRUTIL SUBCHANNEL' This will provide a very comprehensive analyss of each sector on the disc, but can take longer than using DRUTIL CDTEXT.
By following the above steps on each new master that is created, we can ensure that all the information we require a master CD to contain, is present on the disc prior to sending the disc for replication.
Fig 1: Above image shows the Terminal window in OSX, DrUtil can be used to perform a range of tasks
Fig 2: In the above image, Terminal has been used to run DRUTIL CDTEXT, this gives all the meta-data contained on the disc. We can see the CD Text, ISRC codes, and the barcode number or MCN.