Tutorial #8 - How to Reduce (Existing) CDLC File Size

Like me, you may have some CDLC songs that have huge file sizes compared to most other CDLC.  Take a look at your CDLC file sizes and look for any that are hogging up your disk space.  The song length and encoding bit rate have the most effect on audio file size.

As a point of reference, most official DLC are 4MB to 8MB in size and are encoded at a VBR of 128kbps.  These are good file size numbers to shoot for if you are producing CDLC. 

In this short tutorial, you will learn how to reduce the size the audio portion of an existing CDLC in order to reduce the overall file size.  Reducing the CDLC files size has the added benefit that the resulting song loads and plays better, without any discernible loss in audio quality for most.  Audio quality (encoding bit rate) changes can be done using latest beta version of the toolkit (CST).

About 90% of a CDLC file’s size can be attributed to its audio content (the CDLC used in this tutorial is 29 minutes long, is encoded at a VBR of 192kbps, and has a file size of 42 MB).  So if we lower the encoding bit rate, we can reduce the overall size of the CDLC file by almost half to 21.9 MB.

  • Open up CST (the toolkit).
  • Select the Creator tab and click on “Import Package”.  Select a CDLC that you would like to reduce the file size.
  • In the “Files” group box, select the second browse button to open an audio file.  
  • Go to the CDLC’s EOF folder and select the main audio “*.ogg” file. Make sure you did not select the “*_preveiw.ogg” file by accident.  Click “Open”.

  • Now change the “Audio Quality” to “2” and click “Generate”. 


The initial ogg audio file size was 42 MB.  Reducing the ogg audio quality reduced the files size to 21.9 MB.  The resulting CDLC is almost half the size of the original. 

Try this for all your big CDLC files to reclaim your disk space.