MPMan MP-E2004, Руководство пользователя

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Terminology
Bitrate
Bitrate: Data bit amount per unit time. Its unit is expressed as bps (bit/sec).
Data bit means the data used in replaying the sound. As Bitrate becomes larger,
the amount of data used for replaying the sound becomes larger resulting in
better sound quality, however the file size becomes larger. On the other hand,
as Bitrate is smaller the file size gets smaller while the sound quality is decreased.
In general, Bitrate of 128kps in MP3 format and 64kps in WMA format are known
to reproduce CD quality sound. In this case, the WMA file that is similar sound
quality as MP3 is half the sizes of that MP3 file. When MP3 and WMA are created
with same Bitrate, the sizes of the two files become same.
Sampling Rate
The voice or sound signals need to be evaluated per certain period of time
to make voice or sound signal into a digital file such as MP3. The number of
evaluation per unit time is called Sampling Rate. When the sampling rate is high,
the sound quality becomes better. On the other hand, when the sampling rate is
low, even though the sound quality is lowered, the data amount is reduced.
In general audio CD, the sampling rate is 44.1KHz that means sampling occurs
44100 times per second to create 16 bit stereo data. On the other hand, when
a person's voice is recorded, 8Khz 8bit mono sampling is used generally.
LCD Contrast
This adjusts the contrast between LCD screen and the letter. With high contrast
the letter is more distinct from the background and with low contrast the letter is
indistinct from the background. In general, contrast only adjusts clearness of
the letter from the background, when the contrast of this product is set too higher
the background gets darker along with the letter. The contrast can be optimized
to the user's taste.