Use of the MP3 format with Total Recorder is entirely optional and at the user's discretion.

High Criteria has not written, and does not supply, an MP3 encoding or decoding engine with Total Recorder. Instead, Total Recorder can invoke and use the standard encoding and decoding engines that are part of the Windows operating system package or that are bundled with third-party software such as Cyberlink's MP3 Power Encoder. Total Recorder is also compatible with two popular DLLs that may be used to create MP3 files. These two DLLs are called Lame (lame_enc.dll) and Blade (bladeenc.dll). They are available from a number of Internet sites as well as being part of some third-party software packages. However, we recommend that you use Lame Dll, since Blade Dll is no longer supported by its developers and is known to cause problems.

Virtually all new computers come with an MP3 encoding/decoding engine because it is included with the newer versions of Windows, such as Windows ME and Windows XP. In such cases, it will automatically appear in Total Recorder just like any other available compression facility. This Windows standard engine may limit the choice of bit rates. The standard compression engine is found in a file named l3codeca.acm.

As an alternative, you can use Total Recorder to record an uncompressed file and later use your favorite MP3 software, such as MusicMatch Jukebox, or one of the hundreds of other freeware or commercial programs, to perform the compression.