User manual

Encoding quality: The quality of the psycho-
acoustic model with Nero is excellent. Naturally, a
compromise needs to be found between the
complexity of the model and the computing time
needed. Depending on the intended application of
the mp3PRO file, the quality of the encoding (i.e. of
the acoustic model) can be set at 'fast', 'medium'
and 'highest'. With the highest quality, encoding
takes place at approx. normal speed on a PII350,
i.e. three minutes of music will be encoded in three
minutes. At the 'fast' setting (and with the same
hardware), encoding can take place at up to eight
times the normal speed. The sound quality is
already very good with the 'fast' setting and
completely satisfactory for most applications.
Bitrate: 'Bitrate' means the number of bits stored
per second in the mp3 file. The higher this is, the
smaller the amount of information that has to be
removed from the original sound file. Therefore the
higher the bitrate, the better the sound quality. Of
course, the price paid for this sound quality is a
larger file. The mp3PRO file format lets you encode
at either a constant or a variable bitrate (VBR).
Select the option you prefer and specify the bitrate.
Constant bitrate: A bitrate of 64 KB per second has
proved itself to be a fairly good compromise
between sound quality and file size. At this bitrate,
audio files, very roughly speaking, are compressed
by somewhat more than a factor of 20. This means
that a normal track of around three to four minutes in
length (in CD quality; in other words 44.1 kHz, 16
Bit, stereo) can be compressed to a 1.5 - 2
megabyte mp3PRO file by these means.
Once you are satisfied with the settings, click on the
'OK' button to close the dialog or make additional
alterations to the expert settings.