Sony CDP-XA555ES - Manual (Page 9)

Playing CDs
9 GB
Sharp roll-off filter Slow roll-off filter
Pre-ringing Post-ringing Pre-ringing Post-ringing
Comparison of impulse response for sharp roll-off filter
and slow roll-off filter
-120
0
0 22.05k
Response
(dB)
(Slow roll-off filter)
(Sharp roll-off filter)
Frequency (Hz)
Comparison of cutoff characteristics for sharp roll-off filter
and slow roll-off filter
What is a variable coefficient (V.C.) digital
filter?
CD players use digital filters to eliminate the noise
generated during sampling. You can change the tone of
your music by changing the cutoff characteristics of the
digital filter.
Sharp roll-off and slow roll-off
Digital filters can be roughly classified into sharp roll-
off types and slow roll-off types, according to their
cutoff characteristics.
Sharp roll-off filters quickly cut off noise over
22.05 kHz generated during sampling. This is a
superior way of completely reproducing signals below
20 kHz and is the basic principle behind digital audio.
On the other hand, slow roll-off filters cut off noise
generated during sampling, and are able to hold pre-
ringing and post-ringing (a kind of sound smearing) in
the impulse response signal to a minimum.
Note
The Digital Filter function primarily changes characteristics
outside the audible frequency. They cannot affect changes
within the audible frequency such as those provided by the
tone controls of the amplifier. Therefore, with certain
combinations of hardware and software, there may be no
noticeable effect after switching the filter.
Using the Display
You can check information about the disc using the
display.
TIME
DISPLAY MODE
Checking the total number and playing
time of the tracks
Press TIME before you start playing.
The display shows the total number of tracks, total
playing time, and music calendar.
Total playing time Total number of
tracks Music calendar
TIME
1 2 3 4 5
6 7 8 9 10
MIN SEC
While in Shuffle Play mode (“SHUFFLE” appears in
the display; see page 12), a one-second access time
blank is added between each track. This increase is
automatically added to the total playing time in the
display.
If the disc has more than 15 tracks, the z indication
appears next to 15 on the music calendar.
The information also appears when you press
§ OPEN/CLOSE to close the disc tray.