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17

The conventional low-pass filter is comprised of a coil (L) and capacitor (C). As this LC low-pass filter allows sound signals to pass

through the coil, it can deteriorate sound quality. For this reason, the GIC low-pass filter has a circuit (D) equivalent to an LC low-pass filter
that allows resistance (R) causing little deterioration of sound signal quality to pass through.

With two GIC low-pass filters (IC108, IC109, IC208 and IC209) and a capacitor, a 5th order low-pass filter is created.

D

=

+
-

+

-

The CUSTOM/STANDARD switch (S173) is detected with the expander’s FILSET terminal (Pin wj of IC711). A-FIL terminal (Pin tf

of IC711) output is switched to relays (RY101, RY102, RY201 and RY202) through the inverter (IC727), transmitter (IC761), Q304, PHD302,
and Q303, switching the low-pass filter’s characteristics.

The analog sound signals output from the low-pass filter are input to the operational amp (IC104 and IC204) and buffer amp. Buffer amp

output applies a return with the DC servo circuits (IC104 and IC204), suppressing DC offset.

Sound signals are output from the UNBALANCED LINE OUT terminal. They are also output to the BAL board’s line amps (IC171 and

IC271) and output from the BALANCED LINE OUT terminal.

BALANCED LINE OUT terminal output is switched by switching the relay (RY170) with the BALANCED OUT ON/OFF switch

(S170).

D

D

2nd Order

1st Order

2nd Order

Total: 5th Order

18

The DVD-RFP signal detected with the optical block is input to the RF amp (IC001). The RF signal is output from the SIGO terminal (Pin

tj

 of IC001).

The RF signal input to the ARP’s RFIN1 terminal (Pin q; of IC702) is subjected to A/D conversion. After EFM plus decoding and

deinterleaving have been done using 16Mbit DRAM, the DSD stream signal is output from the SD0 to SD7 terminals (Pins oh to ol and
<z/z

 to <z/f of IC702) to the DSD decoder (IC703).

The DSD stream signal is output from the ARP’s SD0 to SD7 terminals and input to the DSD decoder (Pins oa to ol of IC703). The DSD

decoder decodes the DSD streams using 16Mbyte DRAM (IC709), and the 1-bit audio data stream signal for each channel is output from the
DSAL and DSAR terminals (Pins rj and rk of IC703).
When the DSD streams are decoded, TOC information (number of tracks, time, text information, etc.) is read and transmitted to the micro-
processor (IC701) as serial data.

One-bit audio data stream signals are input to the digital filter’s SDATAL and SDATAR terminals (Pins td and ts of IC301) via the

inverter (IC725) and transmitters (IC772 and IC773).

With the expander’s MODE signals (Pin td of IC711), digital filter operations are switched to correspond to CDs or SACDs. For SACDs,

signals are converted to high-precision DSD signals from which switching distortion has been removed with the digital filter’s internal ACP
system. They are output to the S-TACT pulse generator with the 4 signals for every 2 bits (NSDOR 3 to 4 and NSDOL 3 to 4).

ACP is a system that removes the switching distortion that occurs in pulse signals. Although switching distortion occurs in pulse signals,
it occurs when data signals reverse. In keeping, depending on the arrangement of DSD signal data, distortion may occur irregularly.
With ACP, DSD signals are converted to signals that reverse,  within every one data cycle (1/64fs: fs = 44.1kHz). When data is 1 and 0,
pulses are mutually supplementary. Thus, within one piece of data, the up edge and the down edge must exist one time, and as the amount
of change from switching distortion in the amplitude direction becomes a component of direct current (DC) of a fixed value, distortion of
DSD signals is not allowed.

The following circuit operations are the same as in “CD Layer Playback” on page 16.

5.  Pulse waveform generation
6.  Analog signal processing
7.  Low-pass filter
8.  Balanced and unbalanced output

ACP
 signal

DSD
 signal

1

0

0

1

1

Switching Distortion

19

If the set will not be used for a long time, remove the stabilizer in order to protect the spindle motor. In addition, make sure to remove the

stabilizer when shipping the player.

If the spindle motor’s turntable is dirty, clean it with a cotton tip dipped in alcohol.

Over long-term use, the loading panel’s cushions could be damaged. Look over the cushions and replace them as necessary.

Installing the spindle motor in the innermost or outermost part will damage the IN/OUT limit switch. Install the motor in the middle.
In addition, when installing the spindle motor, press down slightly on its rack. (See p. 9 of the Service Manual for Technical Service,

upper diagram 1.)

When replacing the optical block, make sure to remove the RF board.
When the RF board has been removed, it will be possible to remove the soldering on the short lands for preventing damage from static

electricity on the optical block, after the optical block’s flexible board has been connected to the RF board.

After the optical block has been installed, confirm the position of leaf spring Z (see p. 58 of the Service Manual for Technical Service,

ref. no. 453). If this spring is not inserted in a position that holds down the optical block, the tilt motor will not rotate correctly.

After adjusting the optical block’s height, fixate the adjustment screw with a screw lock.

20

The following jigs are necessary for electrical adjustments, etc.

With the first-generation SACD player, adjustments are made with discs that have special reflection rates. For this reason, other test discs

cannot be used for adjustments.

When adjusting other SACD players, do not use test discs other than the SATD-S4.

Table 3-1. Test Discs for the First-Generation SACD

Name

Type

Usage Purpose

SATD-S1

8cm single layer

Mechanical adjustments

SATD-S2

12cm single layer

Reference for electrical adjustments

SATD-S3

12cm dual layer

Reference for electrical adjustments

SATD-S4

12cm single layer

Confirmation when sound quality is poor

TCD-784

12cm CD

Reference for electrical adjustments

To set the test mode with the electrical adjustments, the remote control for CDs is necessary. When using the remote control provided,

both it and the set’s remote control code should be set to CD1.

The CD’s remote control, which has a ten-key pad, can substitute for any remote control. In the Service Manual, an inexpensive remote

control, the RM-D950 (P/N:1-473-944-1) is used.

For confirming and adjusting the main board under the CDM in operating condition, there are two extension cords (P/N: J-2501-164-A)

that connect the main board and CDM.

This board is necessary to prevent the CDM from contacting other boards or the chassis when a CDM is removed using extension cords.

As the CDM will vibrate a fair amount when the automatically adjusted tilt servo is being adjusted, a high-strength board used - wood,

plastic, etc. - should be used.

Following are the two test modes for adjustments.

This mode is used for electrical adjustments other than CLV jitter adjustment. Test mode operations are set with the remote control.
As this mode is set to operate without the detection signals for loading panel opening and closing and stabilizer existence input, make sure

never to connect these cables when adjustment 1 mode has been set.

As procedural errors in adjustment 1 mode could damage the optical block, only confirm those operations that the Service Manual

provides instruction for.

This mode is used only for CLV jitter adjustment and to confirm the set operations when the top board has been removed.
This mode is set to operate normally without the detection signals for loading panel opening and closing and stabilizer existence input. For

this reason, make sure never to connect these cables when adjustment 2 mode has been set.