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– 5 –

Speakers

7th-order        

(delta-sigma) 

modulator 

1-bit coding LSI

Fixed-voltage 

high-speed 

switching circuit

Low-pass

filter network

1-bit

control signals 

Power  amplifier switching

signal

Out- put

Fixed voltage

Analog signal

Multi-bit digital signal

(32kHz, 44.1kHz, 48kHz)

1-bit signal

Over-

sampling

Direct input

(delta-sigma) dynamic feedback

This product uses 1-bit signals as control signals. 

As a result, amplification which maintains a

1-bit signal performance is realized by switching the fixed-voltage power with precise quartz-

crystal accuracy

.

Adopting the concept of “ 

 (delta-sigma) Dynamic Feedback”, this product enables stable am-

plification faithful to the original sound by sending back the power voltage fluctuations (which

af

fects the audio signal) to the “7th-order 

 (delta-sigma) modulator 1-bit coding LSI” which

corrects the 1-bit control signal in real time.

Sampling the input signal at a high-frequency approx. 2.8 MHz (64fs), the 

 (delta-sigma) modu-

lation circuit yields a 1-bit signal stream which faithfully reproduces the original sound.

In this 7-th order 

 (delta-sigma) modulation block, the quantization noise is shifted to higher

range to generate 1-bit signals which secure high signal to noise ratio in the playback band.

Using these 1-bit signals as control signals, the fixed-voltage high-speed switching circuit is con-

trolled. 

The signals abstracted from the switching circuit are sent to the low-pass filter network and

used to drive speakers.

This amplifier has no analog amplifier elements and can obtain speaker driving power by “creating

1-bit control signals through high-speed sampling” and “synchronized high-speed switching to the

sampling frequency”. In consequence, amplification with excellent movement and transient char-

acteristics is fulfilled.

The voltage used by this product varies, depend-

ing on the shipping destination. Check if the

voltage written on the rear panel of the unit is

suitable for that of your country

.

Plug the 

AC power cord into a convenient

AC socket, after any connections.

Unplug the 

AC power cord from the 

AC

socket if the unit will not be in use for a

prolonged period of time.

Never use a power cord other than the one

supplied. Use of a power cord other than

the one supplied may cause an electric

shock or fire.

In areas (or countries) where an 

AC socket

as shown in illustration 

2

 is used, connect

the unit using the 

AC plug adaptor supplied

with the unit, as illustrated. 

The 

AC plug adap-

tor is not included in areas where the 

AC wall

socket and 

AC power plug can be directly

connected (see illustration 

1

).

An 

AC plug adaptor is not supplied if the cord

has an 

Australian Standard plug.

1

2

T

o

 AC  INPUT

T

o

 an 

AC socket

Be sure that the power is turned OFF when

connecting the speaker cord. Failure to

turn the power of

f can result in a short cir-

cuit that will place the amplifier into the

protection circuit mode and cause the

amplifier to shut down. If this occurs, make

sure that the amplifier is of

f, then discon-

nect the power cord from the socket to re-

set the circuit breaker

. 

Y

ou can then re-

connect the cord to use the amplifier

.

Make sure to set the volume to the mini-

mum sound level before turning on the

amplifier power or performing any input

switching. Failure to do this may result in

damage to your speaker system.

The supply voltage of the switching circuit

is not linked with volume adjustment.

Therefore, a constant voltage is supplied

even if not playing back sound and residual

sound may be generated slightly such as

when the volume is turned up. This is nor-

mal.

If this product is subjected to strong exter-

nal interference (excessive shock, static

electricity

, abnormal supply voltage due to

lightning, etc.) or if it is operated incor-

rectly

, it may malfunction.

In such a case, turn the power of

f.

T

urn the power on again and check that the

product works normally

.

(If problems still occur

, contact the dealer

.)

– 6 –

Caution on Disassembly
Follow the below-mentioned notes when disassembling
the unit and reassembling it, to keep it safe and ensure
excellent performance:
1. Be sure to remove the power supply plug from the wall

outlet before starting to disassemble the unit.

2. Take off nylon bands or wire holders where they need to

be removed when disassembling the unit. After servicing
the unit, be sure to rearrange the leads where they were
before disassembling.

3. Take sufficient care on static electricity of integrated

circuits and other circuits when servicing.

1

Top Panel B

1. Hexagon Screw
     (2.5mm) ................. (A1) x2

6-1

2

Top Panel A

1. Hexagon Screw
     (2.5mm) ................. (B1) x6

6-1

3

Side Panel, Sub

1. Screw .................... (C1) x4

6-1

(Left/Right)

4

Side Panel

1. Screw .................. (D1) x18 6-1, 6-2

(Left/Right)

5

Connect Bracket B 1. Screw ..................... (E1) x2

6-2

6

Connect Bracket A 1. Screw ................... (F1) x12

6-3

7

Shield Cover A

1. Screw .................. (G1) x14 6-3, 7-1

8

Shield Cover B

1. Screw .................. (H1) x12

7-1

9

Shield Cover C

1. Screw ..................... (J1) x7

7-1

10

Rear Panel

1. Screw ................... (K1) x14

6-3

2. Socket .................... (K2) x4
3. Soldering ................ (K3) x4

7-5

11

Digital PWB

1. Screw ..................... (L1) x5

7-2

2. Socket .................... (L2) x5

12

Main PWB/Power 1. Screw .................. (M1) x10

7-2

Support PWB

2. Hexagon Specer ... (M2) x5
3. Socket ................... (M3) x8 7-2, 7-5

13

Relay PWB

1. Screw .................... (N1) x3

7-2

14

Power Filter PWB 1. Screw ..................... (P1) x6

7-2

2. Socket .................... (P2) x2

15

Main Volume

1. Screw .................... (Q1) x6

7-2

PWB(Note 1)

2. Hexagon Screw
     (1.5mm) ................ (Q2) x2
3. Nut ......................... (Q3) x1

16

Power Heat Cover 1. Hexagon Screw
(Note 1)

     (1.5mm) ................ (R1) x2

7-3

2. Screw .................... (R2) x8

17

Power Switch

1. Screw ................... (S1) x16

7-3

PWB/Power PWB

18

Bottom Panel

1. Screw ................... (T1) x13

7-4

19

1Bit Amp PWB

1. Screw .................... (U1) x8

7-5

20

Front Panel

1. Screw ..................... (V1) x6

7-6

21

LED PWB

1. Screw .................... (W1) x4

7-7

2. Socket ................... (W2) x1

22

Display Volume

1. Screw ..................... (X1) x1

7-7

PWB (Note 1)

2. Knob ....................... (X2) x1

3. Nut .......................... (X3) x1
4. Socket .................... (X4) x1

23

Front Panel

1. Screw .................... (Y1) 12

7-7

Bracket

24

Switch1 PWB/

1. Screw ................... (Z1) x13

7-7

System Micro-
conputer PWB

(D1)x3
ø3x8mm

(D1)x3
ø3x8mm

(C1)x4
ø3x14mm

(A1)x2
ø4x12mm

(B1)x6
ø4x12mm

Front Panel

Top Panel A

Top Panel B

Side Panel
(Left)

Side Panel
Sub (Left)

Side Panel
(Right)

Side Panel
Sub (Right)

Rear Panel

Front
Panel

Connect
Bracket B

Side Panel
(Left)

Side Panel
(Right)

Rear Panel

(E1)x2
ø3x6mm

(D1)x2
ø3x6mm

(D1)x2
ø3x6mm

(D1)x4
ø3x10mm

(D1)x4
ø3x10mm

Connect
Bracket A

Connect
Bracket A

Front
Panel

Rear Panel

(F1)x2
ø3x6mm

(F1)x2
ø3x6mm

(G1)x2
ø3x25mm

(G1)x2
ø3x20mm

(F1)x4
ø3x6mm

(F1)x4
ø3x6mm

(K1)x1
ø3x6mm

(K1)x4
ø3x6mm

(K1)x2
ø3x10mm

(K1)x5
ø3x6mm

(K1)x2
ø3x6mm

Shield
Cover A

– 7 –

(L1)x5
ø3x6mm

(L2)x3

(M3)x3

(L2)x2

Main PWB

Digital PWB

Relay PWB

Power Filter
PWB

(P1)x2
ø3x6mm

(P1)x4
ø3x6mm

(M1)x2
ø3x6mm

(N1)x3
ø3x6mm

(M1)x4
ø3x6mm

(M2)x5
h20mm

(M1)x4

ø3x6mm

(P2)x2

(Q1)x6
ø3x6mm

(Q3)x1

(Q2)x2

(M3)x2

Washer

Power

Support

PWB

1Bit Amp
PWB

Main Volume PWB

(U1)x4
ø3x16mm

(U1)x2
ø3x8mm

(M3)x1

(K2)x4

Soldering
(K3)x4

Main PWB

(U1)x2
ø3x8mm

(M3)x2

Washer

(S1)x6

ø3x12mm

(R2)x6
ø3x6mm

(R2)x2
ø3x8mm

(S1)x4
ø3x10mm

(S1)x6
ø3x12mm

Power Switch
PWB

(R1)x2

Power PWB

Powet Heat
Cover

Shield
Cover B

Shield
Cover C

Shield
Cover A

(H1)x6
ø3x8mm

(H1)x5
ø3x6mm

(H1)x1
ø3x6mm

(J1)x3
ø3x6mm

(J1)x4
ø3x8mm

(G1)x4
ø3x6mm

(G1)x3
ø3x6mm

(G1)x3
ø3x6mm

Bottom
Panel

(T1)x2
ø3x12mm

(T1)x7
ø3x6mm

Main Chassis

Rear Panle

(T1)x4
ø3x12mm

(V1)x1
ø3x6mm

(V1)x4
ø3x6mm

(V1)x1
ø3x6mm

Front Panel

Main Chassis

(Z1)x5
ø2.6x5mm

(X1)x1 (X2)x1

(X3)x1

(X4)x1

(W1)x4
ø3x6mm

(W2)x1

(Y1)x12
ø3x6mm

(Z1)x8
ø2.6x5mm

System
Microcomputer
PWB

Switch1 PWB 

Front
Panel

Front Panel
Bracket

LED PWB

Display Volume
PWB

Washer

– 8 –

Note 1:
Positioning the volume joints
1. Rotate the sub volume shaft (inside of the set) so that the

flat side faces upward. Fasten the joints in numerical order
as shown in the in the figure.

2. Rotate anticlockwise both the main and sub shafts to mini-

mum level.

3. Slide the connecting shaft until it hits the joint coupling

sleeve.

4. Rotate the joint coupling and connecting shaft so that the

hexagonal screws face the direction of 12 and 9 o'clock.
Fasten the screw that face 12 o'clock.

5. Rotate the shaft and fasten the other hexagonal screws.
6. Rotate the volume shaft so that the flat side faces downward.

Fasten the hexagonal screw from below.

1 (Fasten)

2 (Fasten)

Sub Volume

Joint
Coupling

Fasten

Fasten

Fasten

Fasten

Keep the default setting,
 "each interval = 1 mm."

Sleeve

Hub

Hub

Fasten

Volume
Knob

Volume Connecting Shaft

Joint Coupling