User manual

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SACD Operation
CD and SACD discs have a totally different data structure.
For a CD recording the analogue signal is sampled at a
high rate (44.100 samples / second). The audio signals
have to be bandwidth limited before the sampling process
to get rid of signal components above 20 kHz because
these could not be correctly digitised.
The 20 kHz bandwidth limiting is not necessary for SACD
recordings. It is thus possible to record and store audio
frequencies up to 100 kHz on SACDs. However, all SACD
recordings use a process call “noise shaping” to achieve a
dynamic range comparable to CD systems. This noise
shaping leads to a substantial amount of high frequency
noise in the range 40 . . . 100 kHz.
There is a practical problem with the noise shaping; the
high frequency noise associated with SACD recordings
can not be handled by all amplifier and speaker systems.
In some of these the high frequency signals contained on
SACDs lead to distortion and thus degrade the sound
quality. In such cases it is necessary to limit the bandwidth
of the system to about 40 kHz. This would mean to
sacrifice the main advantage of the SACD system.
To get the best possible performance out of your HiFi
system, the D10 offers analogue and digital signal pro-
cessing means to tailor the analogue output signal exactly
to the requirements of your amplifier and speakers.
These processing means consist of 4 different digital filters
with different bandwidths and different stop band attenu-
ations. (OVS standard, 1, 2, 4). Additionally you can select
the “WIDE” bandwidth mode for the analogue output, if
your system is capable of handling frequencies up to
400 kHz.
With the OVS and WIDE buttons on the front panel you
can experiment and find the combination of oversampling
and analogue processing that delivers the best sonic
results with your equipment.
 Amplifiers are very linear devices having a very wide
bandwidth. So you can use all possible OVS/WIDE combi-
nations without limitation. We recommend a wide band-
width configuration using OVS 1 or 3 with our amps.
Standard OVS
This filter introduces a slight limitation of the high
frequency bandwidth. It is suited for most amplifier /
speaker systems.
OVS 1
This filter features a wider frequency range. Amplifiers
with at least 100 kHz bandwidth are required.
OVS 2
This filter has the narrowest bandwidth and is recom-
mended for amplifiers with a frequency response
< 50 kHz.
OVS 3
This filter introduces no bandwidth limitation of the audio
signals. A very good amplifier / speaker combination
which can handle signals above 250 kHz without
problems is required.