User guide

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• If you primarily listen to stereo CDs and MP3s, a two-channel system will sound almost as
good and will cost a lot less.
7. FILE FORMATS
• ape - the .ape file format from Monkey's Audio is claimed to give about 50% compression
without loss in audio quality.
• atrac (.oma, .omg, .atp) - the newer style Sony proprietary format designed for minidisc use.
It always has a .oma, .omg or .atp file extension. It is similar to mp3 and probably only useful
if you are reading files from minidiscs or writing for minidiscs. (Adaptive Trans-form Acoustic
Coding) - Sony’s, used in MiniDiscs, DATs (digital audio tapes), SDDS theater sound, and
Sony’s MP3 players.
• atrac (.wav) - the older style Sony ATRAC format. It always has a .wav file extension. To
open these files simply install the ATRAC3 drivers.
• au - the standard audio file format used by Sun, Unix and Java. The audio in au files can be
PCM or compressed with the ulaw, alaw or G729 codecs.
• aac - the Advanced Audio Coding format (aac) is a particular codec, or encoding scheme. It
is used in Apple iPods and iPods by Hewlett Packard.based on the MPEG4 audio standard
owned by Dolby. A copy-protected version of this format has been developed by Apple for
use in music downloaded from their iTunes Music Store.
• aiff - the standard audio file format used by Apple. It is like a wav file for the Mac.
• dss - Digital Speech Standard files are an Olympus proprietary format. It is a fairly old and
poor codec. Prefer gsm or mp3 where the recorder allows.
• dvf - a Sony proprietary format for compressed voice files; commonly used by Sony dictation
recorders. You might need a Sony plugin to load this.
• dct - A variable codec format designed for dictation. It has dictation header information and
can be encrypted (often required by medical confidentiality laws).
• flac - a lossless compression codec. You can think of lossless compression as like zip, but
for audio. If you compress a PCM file to flac and then restore it again it will be a perfect copy
of the original. other codecs are lossy which means a small part of the quality is lost). The
cost of this losslessness is that the compression ratio is not good.
• gsm - designed for telphony use in Europe, gsm is a very practical format for telephone
quality voice. It makes a good compromise between file size and quality. This format is
recommended for voice - wav files can also be encoded with the gsm codec.
• midi - not an audio file format really – it is a list of musical notes which a synthesizer can
play.
• mp3 - the MPEG Layer 3 Audio format is the most popular format for downloading and
storing music and is easily transferred to your Sansa SanDisk MP3 player, in this class.
By eliminating portions of the audio file that are essentially inaudible, mp3 files are
compressed to roughly one-tenth the size of an equivalent PCM file while maintaining good
audio quality - not that good for voice storage. MP3 (MPEG-1 Layer 3) Refers to a specific
codec’s outputted digital audio file - many new players can play both MP3 and WMA file
formats - MP3 is an abbreviation for Motion Picture Experts Group Level 3. A format for
compressing files so they'll not only take up less memory, they'll also download faster. MP3
is not the only compression system used, but currently it is the best known. Many players are
called MP3 players, regardless of the type of compression system they use.