What is the difference between VBR files and CBR MP3 files?

[Paul Sanders (AlpineSoft)]

A few people have asked us this question so we thought we would try and clarify matters.

Most people are aware that MP3 is a 'lossy' recording format - i.e. certain information which the human ear finds it hard to detect are discarded when the file is encoded.  If you record to MP3 format, this information is gone for good but most people cannot tell.

VBR files use Variable Bit Rate for encoding different parts of the file.  This generates better quality and / or smaller MP3 files because the encoder can adjust its encoding paramaters according to the complexity of the music (quiet passages can be recorded at lower bitrates, for example, which keeps the filesize down).  CBR files, on the other hand, are recorded at a Constant Bit Rate.  The sort of optimisations that can be carried out when generating VBR files are therefore not available - space is wasted where it could otherwise be saved, and passages of music that require a higher bit rate to sound good cannot be accomodated.

VinylStudio currently generates only VBR files.  This is something we need to address as a few players (not many) cannot play these files, or have problems playing them.  We will address this issue soon, but VBR files are far superior to CBR and are the format of choice for 99.9% of people.  We have actually had no complaints about this but we probably will do one day.

A word also about VinylStudio's MP3 quality settings.  The default setting when recording is 'high'.  This requires about 90MB per album and results in excellent quality recordings which are hard to distinguish from WAV files (which are lossless but require about 500GB per album).  We recommend using this setting for all your recordings if you elect to record to MP3 format (which can save a lot of disk space if you have a large collection).

When generating MP3 files from your split-up tracks, VinylStudio defaults to 'low' quality.  This generates files of comparable size to 'standard' 128 kbps CBR files, but with noticeably better quality.  But if you record to MP3 format, your files may be larger than this.  This is because VinylStudio does 'lossless' (i.e. verbatim) MP3 to MP3 copies where possible.

There, all sorted out now