While both LAME and Helix create MP3s that are generally of similar form and quality, there are a few notable differences between the encoders. One primary difference is that the Helix encoder creates MP3s about three times faster than LAME. Helix can create these files only in VBR format, while LAME can create either VBR or constant-bitrate MP3s. Each program can append additional information to the file of different sorts. LAME can append ID3 identifying information, while Helix can append table of contents information that allows media players to effectively fast forward through VBR files.

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