Sphinx Project2_MK2 SERVICE MANUAL

SERVICE MANUAL

PROJECT TWO Mk2

PRE-AMP

SPHINX Project Two Mk2 Service Manual

1. UNPACKING.......................................................................................................................................3

2. SPHINX WARRANTY CARD..............................................................................................................3

3. CONTACTING THE MANUFACTURER.............................................................................................3

4. THE PRE-AMP AT A GLANCE ..........................................................................................................4

Front panel................................................................................................................................................... 4

Rear panel ...................................................................................................................................................5

5. OPERATION .......................................................................................................................................6

Power on...................................................................................................................................................... 6

Selecting an input ........................................................................................................................................6

Adjusting the volume level ...........................................................................................................................6

Memory mode..............................................................................................................................................6

Power off...................................................................................................................................................... 6

6. SPHINX REMOTE CONTROL............................................................................................................7

Buttons and LED indication..........................................................................................................................7

Operation.....................................................................................................................................................8

Selecting without switching..........................................................................................................................8

Batteries.......................................................................................................................................................8

Encountering problems................................................................................................................................8

7. TECHNICAL SPECIFICATIONS.........................................................................................................9

8. ADJUSTMENT PROCEDURES........................................................................................................10

Bias and Offset ..........................................................................................................................................10

Initial Set-up...............................................................................................................................................10

Bias / Offset Adjustment ............................................................................................................................10

9. PROBLEMS AND SOLUTIONS .......................................................................................................11

10. DIAGRAMS AND PARTS LISTS....................................................................................................12

Connection Diagram for testing the Project 2 Mk2.....................................................................................13

Schematic overview of Project 2 mainboard..............................................................................................14

Project 2 power supply overview................................................................................................................15

Project 2 power supply...............................................................................................................................16

Project 2 input selection.............................................................................................................................17

Project 2 left pre-amp.................................................................................................................................18

Project 2 right pre-amp ..............................................................................................................................19

Project 2 phase inverter.............................................................................................................................20

Project 2 display.........................................................................................................................................21

PCB drawings of Project 2 Mk2 .................................................................................................................22

Partlist pre-amp..........................................................................................................................................23

Partlist display............................................................................................................................................31

2

SPHINX Project Two Mk2 Service Manual

The Sphinx Project Two Mk2 design principles

The Sphinx Project Two Mk2 was designed for the
ever-increasing group of quality-conscious
audiophiles.
We are very proud of the tradition connected with
the SPHINX name, especially concerning audio
quality perfection.

This service manual will help you to optimally
service and repair the Sphinx Project Two Mk2 Pre­Amp.
This pre-amp is extremely simple to operate and
uses the newest technologies and refined designs.
Designs that have successfully been used in the
award winning Project Eight.
Features include ultra-linear extremely low-noise
Class A audio circuits, built from the finest hand­selected parts.
The signal path is completely balanced from input to
output, and left and right are totally separated.
The power supply is of a unique design (fully Class­A!) and consists of three completely separate and
independent sections: one for the digital control plus
one each for the left and right channel.
The ALPS volume control is motor-controlled.
All settings and controls can also be accessed from
the supplied Sphinx Remote Control.

1. UNPACKING

Before leaving the factory every Project Two Mk2 is
subjected to stringent and extensive technical and
exterior quality inspection. This ensures the user
many years of high quality audio from a perfect­looking product.
We recommend owners to ship the Project Two
Mk2 in its original carton.

After unpacking the Project Two Mk2 we therefore
recommend you carefully check it for any transport
damage.
If you find any damage and the product has not
been shipped in the original carton the ensuring
repair costs will not be covered by the warranty.

2. SPHINX WARRANTY CARD

To be entitled to any warranty repairs the owner
must have send the filled out warranty card to
Sphinx or a distributor where it has been registered.
Other regulations may apply in your specific
country: when in doubt, please consult the proper
authorities.

To obtain the maximum quality from this pre amp it
is necessary for it to be properly aligned and to be
used with top quality audio components, preferably
other Sphinx components.

Please also refer to the User Manual of the
Project Two Mk2 for information about
functions not described in this manual.
It is important to familiarise yourself with the
special functions, operation and possibilities
of the Sphinx Project Two Mk2.

3. CONTACTING THE MANUFACTURER

In case of any problem not covered in this manual
or if you have other questions you may contact the
Sphinx International Service Department in The
Netherlands (local time: GMT +1h) during office
hours at the following numbers:

Telephone [phone]
Fax [phone]
E-mail [e-mail]

It is always very helpful and efficient if you have all
relevant information about the specific product and
the problem ready.

3

SPHINX Project Two Mk2 Service Manual

4. THE PRE-AMP AT A GLANCE

Front panel

1

1 2

1. INPUT: With this rotary knob you may select
one of the six inputs.
Turn clockwise for an input to the right of the
active one, anti-clockwise for an input to the
left.

2. STANDBY: To switch the component on and
off:
on LED is green
off LED is red

3. Receptor window for the IR signals from the
Remote Control.

4. Input selection LED's: The input selected with
knob (1.) is indicated by one of these LED's:
CD SYM balanced CD input
CD unbalanced CD input
TUNER unbalanced Tuner input
LINE 1 unbalanced line input 1
LINE 2 unbalanced line input 2
LINE 3 unbalanced line input 3.

3 5

4 6 7 8

5. MUTE: Press this button to temporarily mute
the sound. The red LED will light.

6. TAPE MON: To select the TAPE IN input. The
red LED will light.

7. PHONES: To connect dynamic stereo
headphones.

8. VOLUME: This rotary knob adjusts the volume
level.

4

SPHINX Project Two Mk2 Service Manual

25

26

Rear panel

9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

9. GROUND: You may directly connect the signal
grounds of other equipment to the signal
ground of the Project Two Mk2.

10. TAPE OUT: Connect this output to the input of
the recorder.

11. TAPE IN: Connect this input to the output of
the recorder.

12. CD: To connect the cinch signal cable from the
CD player.

13. TUNER: To connect the cinch signal cable from
the tuner.

14. LINE 1: To connect the cinch signal cable from
the signal source for LINE 1.

15. LINE 2: To connect the cinch signal cable from
the signal source for LINE 2.

16. LINE 3: To connect the cinch signal cable from
the signal source for LINE 3.

17. CD BALANCED L: To connect the XLR signal
cable (balanced cable) from the left output of
the CD player.

18. CD BALANCED R: To connect the XLR signal
cable (balanced cable) from the right output of
the CD player.

19. BALANCED OUT L: To connect the XLR
signal cable (balanced cable) from the left input
of the power amp.

20. BALANCED OUT R: To connect the XLR
signal cable (balanced cable) from the right
input of the power amp.

21. OUT 1 L+R: Connect this output with a cinch
signal cable to the input of your power amp.

22. OUT 2 L+R: To connect the XLR signal cable
(balanced cable) from the right input of the
extra power amp or surround processor.

23. Control Out: To connect the optical cable
going to another Sphinx component.

24. Warning!: This shows important information
about the safety regulations for the
Project Two Mk2.

25. AC Power: Connect the mains cable to a
mains power outlet (230 - 240 VAC).

26. O / I: This is the mains power switch.

27. Fuse holder: Contains a fuse (500 mA slow).

28. Selector for power supply voltage (120/240
V), (115/230 V).

27 28

5

SPHINX Project Two Mk2 Service Manual

5. OPERATION

Connect the mains cable to a mains outlet.
Once you have finished connecting all components,
you can power on the Project Two Mk2 with the
mains switch O / I (26.).

The volume control will then automatically turn
counter-clockwise and, for a while, the STANDBY
LED will blink red/green, after which it will remain
red.
The pre-amp is now in standby mode.

Power on

You switch the amp on with the STANDBY button.
That way, all circuits will remain at optimum
operating temperatures and the audio quality will be
100% immediately after switching on. Additionally it
significantly increases the life span of the
component.

The pre-amp will select the CD SYM input after
which it un-mutes the output.

Selecting an input

You select the input with the large rotary knob
INPUT:
clockwise to the right of the selected one,
anti-clockwise to the left of the selected one.
Upon reaching LINE 3 or CD SYM you cannot 'roll
over' to CD SYM or LINE 3 respectively.

As long as you move the knob, only the LED's will
change: the current selected input remains active.
The new input only becomes active after you have
selected it and released the INPUT knob.
You will hear a 'click'. This is caused by the precision
relays for the inputs: the 'old' one is released while
the new one is energised.

Adjusting the volume level

The large VOLUME control to the right adjusts the
volume level from OFF to maximum (fully clockwise).
The level change is immediate.

Memory mode

The Project Two Mk2 has a MEMORY mode: it
automatically selects the last input that was active
before you switched the component off with the
stand-by button.

Power off

You switch the Project Two Mk2 off (to stand-by)
with the STANDBY button (2.).

6

SPHINX Project Two Mk2 Service Manual

6. SPHINX REMOTE CONTROL

This single Sphinx Remote Control lets you control
all functions: not only of the Project Two Mk2, but
also of all other Sphinx equipment.

Only the following buttons and indications on the
Remote apply to the Project Two Mk2 (the others
will not function):

Buttons and LED indication

1. PRE-AMP: To select the pre-amp.
All buttons pressed hereafter will control only
the pre-amp functions.
Note: TUNER and CD have no function.

2. STANDBY: Use this button to switch the Project
Two Mk2 to stand-by.

3. : Pressing this button mutes the outputs
(temporarily) and you will not hear any sound.
The red LED will be illuminated. Another press
on this button un-mutes the outputs.

4. TAPE/MONITOR: Use this button to select the
Tape IN input. Pressing this button has the
same effect as pressing the TAPE button on the
front panel.
Note: The LED of the selected input (see 4.) will
remain illuminated.

5. 1 - 6: To select inputs CD SYM to LINE 3
(Note: 7, 8, 9 and 0 do not function):
1 CD SYM balanced CD input
2 CD unbalanced CD input
3 TUNER unbalanced Tuner
4 LINE 1 unbalanced line input 1
5 LINE 2 unbalanced line input 2
6 LINE 3 unbalanced line input 3

6. ñ -button: Pressing this big triangular button has
the same effect as rotating the VOLUME control
on the front panel clockwise. You increase the
volume and the volume control will turn
clockwise.

7. ò -button: Pressing this big triangular button has
the same effect as rotating the VOLUME control
on the front panel anti-clockwise. You decrease
the volume and the volume control will turn
counter-clockwise.

Note: The ñ - and ò -button by default control
volume of the Project Two Mk2 only, even if you
have selected Tuner or CD.

7

SPHINX Project Two Mk2 Service Manual

Operation

The Sphinx Remote is used with several different
models and can therefore transmit different control
codes, depending on which model has been
selected with the select buttons (3.).

Important: Always press the PRE-AMP button
before you send a command (even if you only have
one Sphinx component).

Otherwise it is possible that, although the Remote
sends a signal (LED blinks), nothing happens
because the transmitted signal is not 'recognised'
by the component.
Indoors the Remote may be used up to a distance
of 7 meter, provided there is no strong sunlight in
the room and if you aim the Remote at the
component.
Always aim the Remote straight at the front panel of
the component, the maximum offset angle is 30°.

Selecting without switching

Suppose, for instance, that you would like to select
the Tuner to Radio 4 without interrupting CD
playback.
In that case you momentarily depress (not longer
than 0.5 sec) the 'TUNER' button and the '4' button.
If you depress the select button for longer than 0.5
sec, the system will select a different signal source
(in our example you will then hear the Tuner
playback).

Batteries

The two batteries have a life span of approximately
one year during normal use, but shorter when used
more intensely.
Replacement batteries: 1.5 V, penlight or AAA (one
of these codes is indicated on the packaging and
the batteries). You may also use rechargeable 1.5 V
batteries.

Note: Position the new batteries exactly as shown in
the illustration at the bottom of the battery
compartment, otherwise the remote control does
not function!

Encountering problems...

Remote Control does not work

Wrong component selected Select the correct one
Wrong Remote mode ('Learn'

instead of Normal)
Wrong command programmed Re-program with Learn

Distance to component
exceeds 7 m

Angle between Remote and
component exceeds ±30°

Sensor window on front dirty Clean window
Batteries empty or incorrectly

placed

Strong (sun)light in room Shade off light source
Component is not switched on

(!)
Memory erased Re-program completely

Component reacts differently than expected or
not at all

Wrong component selected Select the correct one
Component or Remote does

not function
Batteries in remote empty Use new batteries

Select correct mode

mode
Use Remote at closer

range
Decrease angle

Use new batteries or
replace the old ones
correctly

Switch it on

Check component with
its original remote

8

SPHINX Project Two Mk2 Service Manual

7. TECHNICAL SPECIFICATIONS

Bandwidth 0 - 500,000 Hz (+0/-3 dB)
Phase response error <0.5°
Gain 18 dB max.
THD+N (IHF-A) <0.0015% (2nd harm., 10 - 20,000 Hz)
IMD <0.003%
S/N ratio (IHF-A) >100dB
Channel separation >100 dB

Inputs 1x XLR balanced

5x cinch unbalanced (gold-plated)
level, nominal (for 1 V output) 0.13 V (-18 dBV)
impedance XLR: 10 kohm / cinch: 50 kohm

Outputs 1x XLR balanced

2x cinch unbalanced (gold-plated)

1x cinch Tape (gold-plated)
level 9.2 V max. (19.3 dBV) (1 - 100,000 Hz, THD

<0.002%)
impedance <10 ohm

Volume control ALPS motorised
channel imbalance less than 2 dB

Sphinx Control 1x optical
Remote control full function
Mechanical decoupling of housing Transrotor absorbing 'pucks'
Power supply external, completely stabilised

Supply capacitance 35,200 µF total
Power consumption 15 W stand-by

17,5 W 'on'
Dimensions (h x w x d) 68 x 482 x 328 mm
Weight 11 kg

This unit conforms to the EMC interference regulations issued by the EU and to the CE standards.
This unit complies with safety regulation VDE 0860 and therefore with international safety regulation IEC 65.

Technical specifications may be changed by SPHINX without prior notice if technical developments make this
necessary.

©1998 Audioscript BV

9

SPHINX Project Two Mk2 Service Manual

8. ADJUSTMENT PROCEDURES

The Project Two Mk2 only has two parameters that
might need adjustment:

- Bias: to set the bias current and bias voltage of
the amplifier.

- Offset: to set the DC-offset voltage of the
output.

These adjustments might be necessary when the
amplifier has been used for a period of time (and
settings have changed due to ageing) or when a
part of the Project Two Mk2 have been replaced.

After opening the Project Two Mk2 (by removing the
6 screws in the bottom), the following sections will
be visible:

- The Mains Transformer.

- The Main Print Board with inputs, outputs, the
dual power supply and both amps.

- The Display Print Board.

Bias and Offset

Both adjustment procedures use the same controls:
potmeters P1 & P2 (Left Channel) and potmeters
P3 & P4 (Right Channel).

Initial Set-up

• Connect a low distortion signal generator
(<0.002% internal distortion) to an input of the
pre-amp.

• Connect the distortion analyser input, the DC
mV-meter and the oscilloscope to an output of
the pre-amp.

Bias / Offset Adjustment

• Short-circuit the input.

• Measure the voltage across resistor R102 (Left)

and R110 (Right). Both should read 9 V (+/- 500
mV).
Adjust the value with potmeter P1 (Left) and
potmeter P3 (Right), see file Pj2Adjust.PDF.
This will set the bias for one side of the
differential amp.
The Offset is not important.

• Measure the voltage across resistor R117
(Right) and R109 (Left). Both should read 9 V
(+/- 500 mV).
Adjust the value with potmeter P4 (Right) and
potmeter P2 (Left), see file Pj2Adjust.PDF.
This will set the bias for the other side of the
differential amp.

At first both Bias parameters should be set (re. the
bias current and bias voltage of output transistors).
The positive and negative bias are adjusted
separately.
This may result in an output DC-offset voltage
which has to be adjusted afterwards.

Proper DC-offset adjustment is very important.

A simple trick will greatly increase the accuracy of
this critical adjustment (see also the drawing titled
“Connection Diagram for testing the Project Two
Mk2” at page 13).
By connecting a DC-coupled power amp to the
Project Two Mk 2 outputs and measuring the offset
at the speaker outputs, the offset is boosted to
around 30 times the original value!

Note: We strongly recommend that you use a power
amp with a very low DC-offset, such as the Project
Eighteen.
Note: The pre-amp and the power amp should be
switched on at least 1 hour before performing this
adjustment so they can reach optimum working
temperatures.

The Offset should now also be correct (<1 mV).
Although due to small variances in components
it may be higher so you have to re-adjust it.

• Turn the volume control to MAX.
The mV-meter should show an Offset of less
than 1 mV. If this is not the case please re­adjust the value with potmeters P1 and P2 (Left)
and/or P3 and P4 (Right).

• Select a 1V / 1 kHz signal at the function
generator.

• Check the output for the correct THD (<0.005%)
and clip-level (>10 V).

• If all values are correct this will indicate the
Project Two Mk2 is properly adjusted and the
procedure is now completed.

10

SPHINX Project Two Mk2 Service Manual

9. PROBLEMS AND SOLUTIONS

At the moment of writing the Project Two Mk2 has
two known specific problems.
If in the future you encounter any problem(s) you
may enter the info in this table. This table can then
be used for future reference.

Problem Cause Solution Refer to

Volume potmeter has not
enough gain range

Overall Gain of pre-amp is too
high

Please also send (by fax or e-mail) the specific
information to the Sphinx International Service
Department (see page 3): this info can then be
added to the general database to aid others.

page/file

Change R76 (left channel)
and R85 (right channel) from
3k33 to 1k8.

Pj2Adjust.PDF

Oscillation problem at balanced
output

Not enough frequency
compensation across U2 and U3

Install a ceramic condenser
(56 pF / 50 V) between pin 2
and pin 6 of U2 and U3

Pj2Adjust.PDF

11

SPHINX Project Two Mk2 Service Manual

10. DIAGRAMS AND PARTS LISTS

The next pages contain a complete set of schematic drawings including the associated parts lists (if applicable).

Connection Diagram for testing the Project 2 Mk2.....................................................................................13

Schematic overview of Project 2 mainboard..............................................................................................14

Project 2 power supply overview................................................................................................................15

Project 2 power supply...............................................................................................................................16

Project 2 input selection.............................................................................................................................17

Project 2 left pre-amp.................................................................................................................................18

Project 2 right pre-amp ..............................................................................................................................19

Project 2 phase inverter.............................................................................................................................20

Project 2 display.........................................................................................................................................21

PCB drawings of Project 2 Mk2 .................................................................................................................22

Partlist pre-amp..........................................................................................................................................23

Partlist display............................................................................................................................................31

12

SPHINX Project Two Mk2 Service Manual

Connection Diagram for testing the Project 2 Mk2

Oscillator

Frequency

Amplitude

THD

THD ANALYZER

gnd

out1 out2

(+) (-) (+) (-)

inp2

inp1

THD out

(+)

(+)

(+)

(-)

A

Left

(-)

A

(-)

Pre-amplfier (3x)

(+)

(+)

(+)

(-)

B

(-)

Right

PRE-AMPLIFIER

(-)

B

SCOOP

Left

Right

Amplfier (30x)

AMPLIFIER

gnd

time/div

x

y

inp2

inp1

Scoop

inp2inp1

out1 out2

SWITCH-BOX

13

SPHINX Project Two Mk2 Service Manual

Schematic overview of Project 2 mainboard

INPUT/OUTPUT SELECTION

+D24V

PJ02INP.SCH

+D24V

+D24V

-R-OUT

-R-OUT
+R-OUT

+R-OUT

-L-OUT

-L-OUT
+L-OUT

+L-OUT

+22V

+22V

L-INPUT

L-INPUT

R-INPUT

R-INPUT

+22V

-22V

-22V

-22V

M2

M2
M1

M1

POWER-SUPPLY
PJ02PS.SCH

+22V

+D24V

+22V

+D24V +22V

+D24V

-22V

-22V

CN22

SP4

AGND

SP1

SP2

PHASE-INVERTER
PJ02PH.SCH

+22V

+22V

-L-OUT

-L-OUT
+L-IN

+L-IN

+R-IN

+R-IN

-R-OUT

-R-OUT

-22V

-22V

CN21

AGND

R64
600R

R65
600R

LEFT LINE-AMP
PJ02LAMP.SCH

+22V

+22V+22V+22V

SP6

+L-OUTR

-22V

+22V

SP5

-22V-22V-22V

+L-OUTR

-22V

-22V

RIGHT LINE-AMP
PJ02RAMP.SCH

+22V

+22V

+R-OUTR

+R-OUTR

-22V

-22V

L-INPUT

L-INPUT

R-INPUT

R-INPUT

MP5 AGND

AGND

220P
C77

220P
C78

R142
1K00

R143
1K00

14

SPHINX Project Two Mk2 Service Manual

Project 2 power supply overview

R3

T1
R-CORE 50VA SEC

120V

120V

14V

14V

14V

14V

R1

R1, R3, R4,R8..R11, R17..R120 : 11 X 10R0

B1

R4

+

C3
330U

50V

100N
C2

U1
L7824C

1

Vin

GND

2

DGND

+24V

3

100N
C1

+D24V

100N
C64

DGND

AGND

R14
10K0

R19

R20
R17

R18
R11

R10
R9

R8

project-2 analog power supply
pj2aps.sch

U1

U1

U2

U2

U3

U3

U4

U4

+22V

+22V

AGND

AGND

-22V

-22V

+22V

AGND

+22V

15

SPHINX Project Two Mk2 Service Manual

Project 2 power supply

14VAC

14VAC

U1

U2

U3

U4

220N
C11

D7 D8

220N

D6 D5

C8

220N
C6

D1D4D2

220N
C5

220N
C10

220N
C9

+

C15

+

C12
220N
C7

220N

D3

C4

R21
10R0

R22
10R0

+

+

C16

C17

+

+

C14

C13

R15
10R0

R16
10R0
R12
10R0

R13
10R0

R6
10R0

R7
10R0

+

+

C24

C23

+

+

C21

C20

D1..D8 : 8 X 1N4001
C12..C17

C20..C25 : 16 X 2200U/63V
C40..C43

+

C25

+

C22

T3
A1306

R32
8R6

LD2
LED red

220N
C29

220N
C28

LD1

LED red
R31
8R6

T2
C3298

220N
C37

R50
10K0

R35
10K0

220N

C36

T5
A1306

T4
C3298

R49
10K0

R48
2K00

R37
2K00

T8
A970

R36
10K0

R46

R47

332R

332R

T7

T9

C2240

C2240

R44
1K00

R45

+

150R

C33
330U/50V

+

R40

C32

150R

330U/50V
T6
A970

R41
1K00

R38

R39

332R

332R

R43
10K0

LED red
LD6
LED red
LD5

LED red
LD4
LED red
LD3

R42
10K0

+

C43+C42

+

C40+C41 C44

+22V (+/-1V)

+22V

220N
C45

AGND

AGND

220N

-22V

-22V (+/-1V)

16

SPHINX Project Two Mk2 Service Manual

Project 2 input selection

CDTUNERLINE 1LINE 2LINE 3TAPE INTAPE OUTOUT 1OUT 2OUT 3 CD SYM

CN2

132

+D24V

RL1

+

SP3

OGND

R5

-L-OUT +D24V

+L-OUT

-R-OUT
+R-OUT

24R9

CN3

132

OGNDOGND

RL2

+

R23
24R9

O2

R-INPUT

L-INPUT

R144

R145

600R

600R

RL4

RL9

+

O1

O3

AGND

RL6

RL5

+

O4

+

+

O5

CN16ACN16BCN13ACN13BCN1A CN1B CN17A CN17B CN12A

12J212

J5

R70
24R9

R71
24R9

RL8

RL7

+

O6

RL3

+

+

O7

O8

+D24V

O2

DGND

O8
O3
O4
O5
O6

M2

O7

M1

O1

+D24V

R2
4K75

OPT1
OPTOUT

CN19

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18

to display

R60

+22V

+

C48
330U/50V

+

C50
330U/50V

+

C46
330U/50V

+

C38
330U/50V

1R00

R68

-22V

1R00

R52

+22V

1R00

R58

-22V

1R00

AGND

AGND

220N
C49

AGND

AGND

220N
C51

220N
C47

AGND

AGND

220N
C39

AGND

1

R67

3

CN5

2

15K0

AGND

3

R62
5K00

R63
100K

AGND

1

R57

CN4

2

15K0

R54
5K00

R55
100K

AGND

CN20

1

+22V

AGND

4

-22V

CN18

1

AGND

4

C101
33PF

R66
15K0

U5

OPA604AP

R61
5K00

C102
33PF

R56
15K0

U4

OPA604AP

R53
5K00

17

SPHINX Project Two Mk2 Service Manual

Project 2 left pre-amp

CN14

L-INPUT

8
7
6
5
4
3
2
1

+22V (+/-1V)

AGND

-22V (+/-1V)

+22V

LED voltage approx. 1.8V

P2

LED red

LD16

R138
33K2

LED red

LD15

-22V

50R

+

R133

C66

243R

T35
A970

R109

± 4mA

2K21

+

C61

+

C60

R102

± 4mA

2K21

T34
C2240

R130
243R

+

C65

P1
50R

LED red

LD10
LED red

LD9

LED red

LD8
LED red

LD7

T31
C2240

T30
A970

R132
200R

R131
200R

R107
2K21

R104
2K21

R128
100R

R126
100R

D12

R106
2K21

R108
51R0

T22
C2240

T26
K389

R122

R119

100R

200R

C58

R100
10R0

47P

R124

R118

100R

200R

T25
J109

T24
A970

R103
51R0

R105
2K21

D9

R76
4K75

R141
600R

12

J3

+

C73

AGND

10N

R93
600R

C70

AGND AGND

D11

R97
18R0

470P
R90
4K75 C56

C74
330U/50V

AGND

R96
18R0

D10

AGND AGND

R92

10N

600R

C69

T17
A1145

T14
C2705

R79
243R

± 7.5mA± 7.5mA

R73
243R

T16
C2705

T15
A1145

R78
51R0

R74
51R0

R80
100R

C53

T11
A1306

R77
10R0

R75
10R0

T10
C3298

R72
100R

C52

CN9

1

4

+L-OUT

CN6

4

1

+L-OUTR

CN8

4

1

18

SPHINX Project Two Mk2 Service Manual

Project 2 right pre-amp

+22V (+/-1V) LED voltage approx. 1.8V

+22V

LED red

+

P4

C68

LD18

R139
33K2

R-INPUT +R-OUT

8CN15
7
6
5
4
3
2
1

AGND

8PIN

LED red

LD17

-22V

-22V (+/-1V)

50R

R137
243R

T37
A970

R117

± 4mA

2K21

+

C63

+

C62

R110

± 4mA

2K21

T36
C2240

R134
243R

P3

+

50R

C67

LED red

LD13
LED red

LD14

LED red

LD12
LED red

LD11

T33
C2240

T32
A970

R136
200R

R135
200R

R115
2K21

R112
2K21

R129
100R

R127
100R

D16

R114
2K21

R116
51R0

T23
C2240

T29
K389

R123

R121

100R

200R

C59

R101
10R0

47P

R125

R120

100R

200R

T28
J109

T27
A970

R113
2K21

D13

R85
4K75

R140
600R

12

J4

+

C76

AGND

C75
330U/50V

AGND

R91
4K75 C57

AGND

R111
51R0

AGND

10N
C72

470P

10N
C71

R95

R88

600R

243R

± 7.5mA ± 7.5mA

T21
A1145

T20
C2705

D15

R99
18R0

R98
18R0

D14

T19
A1145

T18
C2705

R82

243R
R94
600R

R87
51R0

R83
51R0

AGND

AGND

R89
100R

C55

T13
A1306

R86
10R0

R84
10R0

T12
C3298

R81
100R

C54

CN11

1

4

4PIN

CN7

4

1

4PIN

+R-OUTR

CN10

4

1

4PIN

19

SPHINX Project Two Mk2 Service Manual

CM1

Project 2 phase inverter

+22V

-22V

+22V

-22V

R29
1R00

AGND

R51
1R00

R24
1R00

AGND

R28
1R00

220N
C31

220N
C35

220N
C19

220N
C27

+VR

+

C30
330U/50V

+

C34
330U/50V

-VR

+VL

+

C18
330U/50V

+

C26
330U/50V

-VL

+R-IN

+L-IN

R30
10K0

R25
10K0

OGND

OGND

R33
10K0

R27
10K0

5P6

+VR

-VR

CM2
5P6

+VL

-VL

U3

OPA604AP

U2

OPA604AP

R34

-R-OUT

24R9

R26

-L-OUT

24R9

20

SPHINX Project Two Mk2 Service Manual

C25V/470U

Project 2 display

VCC

R1

5R62

R2

P30

IR1

V+

D

IR

GND

61K9

2

+

C1

C47U/16V

1
3

100NMKT

GND

C9

C5

33p

GND

Input-selector

PFI

GND

U4

8,00000MHz

P32

P33

U5 MAX690

4

PFI

6

WDI

8

VBAT

C7

33p

100NMKT

S1

C8

100NMKT

Standby Tape-mMute

VOUT

PFO
RES

VCC

C6

M

P35

P34

P31

S2

2 1

10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26

1
5
7

U3

Xtal
EXtal
MD1
MD0
NMI
VCC
STBY
GND
nc
P40
P41
P42
P43
P44
P45
P46
P47

S3

2 1

9

P668P657P646P635P624P613P60

RES

S4

2 1

P5027P5128P5229P5330P5431P5532P7033P7134nc35P7236P7337P7438P75/WR39P76/RD40P7741VCC42P27

T7T2SC2240

T6T2SA970

P36

OPTO

R7

10K

T3
T2SC2240

GND

VCC

R8

R10

390R

390R

2nc1

68

P31

P32

P33

P34

P35

P36

P37

H8

VCC

IN1

VCC

T5 T2SC2240

P30

P3061P3162P3263P3364P3465P3566P3667P37

60

P10

59

P11

58

P12

57

P13

56

P14

55

P15

54

P16

53

P17

52

GND

51

nc

50

P20

49

P21

48

P22

47

P23

46

P24

45

P25

44

P26

H8/325 HD6413258CP10

43

GND

IN8
IN7
IN6
IN5
IN4
IN3
IN2

STB

M1M2

T4 T2SA970

CD

TAPE-M

CD-S

LD3 LD4 LD5 LD6 LD7

LD8 LD2

U2
ULN2804

1

IN1

2

IN2

3

IN3

4

IN4

5

IN5

6

IN6

7

IN7

8

IN8

TUNER

LINE1

LINE2

LINE3

MUTE

LD9

R11

390R

10

+24

IN1

OUT1

K

IN2

OUT2

IN3

OUT3

IN4

OUT4

IN5

OUT5

IN6

OUT6

IN7

OUT7

IN8

OUT8

GND

9

GND

GND

18

RL2

17

RL8

16

RL3

15

RL4

14

RL5

13

RL6

12

RL7

11

RL1

+24

PFI

1

R5

39K2

C4
100NMKT

R6

10K

GND

M

T8

T2SA970

U1
MC7805

R9

10K

Vin

T2SC2240

T1

R G

GND

2

GND

R4

10K

T2

T2SA970

STANDBY

LD1

R3

RL1

M1

RL7

M2

RL6

RL5

RL4

RL3

RL8

OPTO

GND

RL2

+24

3

100NMKT

CN1

18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1

18PIN

VCC

C3

+

C2

390R

+5V

PCB 02601B-AS-SISW

1

21

SPHINX Project Two Mk2 Service Manual

PCB drawings of Project 2 Mk2

Because there is a significant image-quality loss during the conversion of the drawings, the PCB-drawings are
located in seperate files.
These files are in PDF-format (Adobé Acrobat 3.0 Reader).

• Pj2Main.PDF for Mainboard

• Pj2Display.PDF for Displayboard

• Pj2Adjust.PDF for adjustment procedures

22

SPHINX Project Two Mk2 Service Manual

Partlist pre-amp

Designator Part Type Description

B1 W02M Bridge rectifier

C1 100nF MKT capacitor
C10 220nF MKT capacitor
C101 33pF Ceramic capacitor
C102 33pF Ceramic capacitor
C11 220nF MKT capacitor
C12 2200uF/63V Electrolytic capacitor
C13 2200uF/63V Electrolytic capacitor
C14 2200uF/63V Electrolytic capacitor
C15 2200uF/63V Electrolytic capacitor
C16 2200uF/63V Electrolytic capacitor
C17 2200uF/63V Electrolytic capacitor
C18 330uF/50V Electrolytic capacitor
C19 220nF MKT capacitor
C2 100nF MKT capacitor
C20 2200uF/63V Electrolytic capacitor
C21 2200uF/63V Electrolytic capacitor
C22 2200uF/63V Electrolytic capacitor
C23 2200uF/63V Electrolytic capacitor
C24 2200uF/63V Electrolytic capacitor
C25 2200uF/63V Electrolytic capacitor
C26 330uF/50V Electrolytic capacitor
C27 220nF MKT capacitor
C28 220nF MKT capacitor
C29 220nF MKT capacitor
C3 330uF/50V Electrolytic capacitor
C30 330uF/50V Electrolytic capacitor
C31 220nF MKT capacitor
C32 330uF/50V Electrolytic capacitor
C33 330uF/50V Electrolytic capacitor
C34 330uF/50V Electrolytic capacitor
C35 220nF MKT capacitor
C36 220nF MKT capacitor
C37 220nF MKT capacitor
C38 330uF/50V Electrolytic capacitor
C39 220nF MKT capacitor
C4 220nF MKT capacitor
C40 2200uF/63V Electrolytic capacitor
C41 2200uF/63V Electrolytic capacitor
C42 2200uF/63V Electrolytic capacitor
C43 2200uF/63V Electrolytic capacitor
C44 220nF MKT capacitor
C45 220nF MKT capacitor
C46 330uF/50V Electrolytic capacitor
C47 220nF MKT capacitor
C48 330uF/50V Electrolytic capacitor
C49 220nF MKT capacitor

23

SPHINX Project Two Mk2 Service Manual

Designator Part Type Description

C5 220nF MKT capacitor
C50 330uF/50V Electrolytic capacitor
C51 220nF MKT capacitor
C52 220nF MKT capacitor
C53 220nF MKT capacitor
C54 220nF MKT capacitor
C55 220nF MKT capacitor
C56 470pF Styroflex capacitor
C57 470pF Styroflex capacitor
C58 47pF Styroflex capacitor
C59 47pF Styroflex capacitor
C6 220nF MKT capacitor
C60 47uF/25V Electrolytic capacitor
C61 47uF/25V Electrolytic capacitor
C62 47uF/25V Electrolytic capacitor
C63 47uF/25V Electrolytic capacitor
C64 100nF MKT capacitor
C65 47uF/25V Electrolytic capacitor
C66 47uF/25V Electrolytic capacitor
C67 47uF/25V Electrolytic capacitor
C68 47uF/25V Electrolytic capacitor
C69 10nF MKT capacitor
C7 220nF MKT capacitor
C70 10nF MKT capacitor
C71 10nF MKT capacitor
C72 10nF MKT capacitor
C73 220nF MKT capacitor
C74 330uF/50V Electrolytic capacitor
C75 330uF/50V Electrolytic capacitor
C76 220nF MKT capacitor
C77 220pF Styroflex capacitor
C78 220pF Styroflex capacitor
C8 220nF MKT capacitor
C9 220nF MKT capacitor
CM1 56pF Ceramic capacitor
CM2 56pF Ceramic capacitor

CN1 CINCH4P Cinch plug
CN10 4PIN 4 pins header
CN11 4PIN 4 pins header
CN12 CINCH2P Cinch plug
CN13 CINCH4P Cinch plug
CN14 8PIN 8 pins header
CN15 8PIN 8 pins header
CN16 CINCH4P Cinch plug
CN17 CINCH4P Cinch plug
CN18 4PIN 4 pins header
CN19 18PIN 4 pins header
CN2 XLR-M XLR connector male
CN20 4PIN 4 pins header

24

SPHINX Project Two Mk2 Service Manual

Designator Part Type Description

CN21 PHONEJACK Phone jack
CN22 KAST_GND Ground connection with case
CN3 XLR-Male XLR connector male
CN4 XLR-Female XLR connector female
CN5 XLR-Female+B51 XLR connector female
CN6 4PIN 4 pins header
CN7 4PIN 4 pins header
CN8 4PIN 4 pins header
CN9 4PIN 4 pins header

D1 1N4001 Diode
D10 1N4148 Diode
D11 1N4148 Diode
D12 1N4148 Diode
D13 1N4148 Diode
D14 1N4148 Diode
D15 1N4148 Diode
D16 1N4148 Diode
D2 1N4001 Diode
D3 1N4001 Diode
D4 1N4001 Diode
D5 1N4001 Diode
D6 1N4001 Diode
D7 1N4001 Diode
D8 1N4001 Diode
D9 1N4148 Diode

J2 Jumper Jumper
J5 Jumper Jumper

LD1 LED red LED red
LD10 LED red LED red
LD11 LED red LED red
LD12 LED red LED red
LD13 LED red LED red
LD14 LED red LED red
LD15 LED red LED red
LD16 LED red LED red
LD17 LED red LED red
LD18 LED red LED red
LD2 LED red LED red
LD3 LED red LED red
LD4 LED red LED red
LD5 LED red LED red
LD6 LED red LED red
LD7 LED red LED red
LD8 LED red LED red
LD9 LED red LED red

OPT1 173298-2 Optical output

25

SPHINX Project Two Mk2 Service Manual

Designator Part Type Description

P1 50R Adjustable pot.
P2 50R Adjustable pot.
P3 50R Adjustable pot.
P4 50R Adjustable pot.
P5 ALPS POT M Stereo motor pot.

R1 10R0 Resistor MRS25
R10 10R0 Resistor MRS25
R100 10R0 Resistor MRS25
R101 10R0 Resistor MRS25
R102 2K21 Resistor MRS25
R103 51R0 Resistor MRS25
R104 2K21 Resistor MRS25
R105 2K21 Resistor MRS25
R106 2K21 Resistor MRS25
R107 2K21 Resistor MRS25
R108 51R0 Resistor MRS25
R109 2K21 Resistor MRS25
R11 10R0 Resistor MRS25
R110 2K21 Resistor MRS25
R111 51R0 Resistor MRS25
R112 2K21 Resistor MRS25
R113 2K21 Resistor MRS25
R114 2K21 Resistor MRS25
R115 2K21 Resistor MRS25
R116 51R0 Resistor MRS25
R117 2K21 Resistor MRS25
R118 200R Resistor MRS25
R119 200R Resistor MRS25
R12 10R0 Resistor MRS25
R120 200R Resistor MRS25
R121 200R Resistor MRS25
R122 100R Resistor MRS25
R123 100R Resistor MRS25
R124 100R Resistor MRS25
R125 100R Resistor MRS25
R126 100R Resistor MRS25
R127 100R Resistor MRS25
R128 100R Resistor MRS25
R129 100R Resistor MRS25
R13 10R0 Resistor MRS25
R130 243R Resistor MRS25
R131 200R Resistor MRS25
R132 200R Resistor MRS25
R133 243R Resistor MRS25
R134 243R Resistor MRS25
R135 200R Resistor MRS25
R136 200R Resistor MRS25
R137 243R Resistor MRS25
R138 33K2 Resistor MRS25

26

SPHINX Project Two Mk2 Service Manual

Designator Part Type Description

R139 33K2 Resistor MRS25
R14 10K0 Resistor MRS25
R140 600R Resistor MRS25
R141 600R Resistor MRS25
R142 1K00 Resistor MRS25
R143 1K00 Resistor MRS25
R144 600R Resistor MRS25
R145 600R Resistor MRS25
R15 10R0 Resistor MRS25
R16 10R0 Resistor MRS25
R17 10R0 Resistor MRS25
R18 10R0 Resistor MRS25
R19 10R0 Resistor MRS25
R2 4K75 Resistor MRS25
R20 10R0 Resistor MRS25
R21 10R0 Resistor MRS25
R22 10R0 Resistor MRS25
R23 24R9 Resistor MRS25
R24 1R00 Resistor MRS25
R25 10K0 Resistor MRS25
R26 24R9 Resistor MRS25
R27 10K0 Resistor MRS25
R28 1R00 Resistor MRS25
R29 1R00 Resistor MRS25
R3 10R0 Resistor MRS25
R30 10K0 Resistor MRS25
R31 8R6 Resistor MRS25
R32 8R6 Resistor MRS25
R33 10K0 Resistor MRS25
R34 24R9 Resistor MRS25
R35 10K0 Resistor MRS25
R36 10K0 Resistor MRS25
R37 2K00 Resistor MRS25
R38 332R Resistor MRS25
R39 332R Resistor MRS25
R4 10R0 Resistor MRS25
R40 150R Resistor MRS25
R41 1K00 Resistor MRS25
R42 10K0 Resistor MRS25
R43 10K0 Resistor MRS25
R44 1K00 Resistor MRS25
R45 150R Resistor MRS25
R46 332R Resistor MRS25
R47 332R Resistor MRS25
R48 2K00 Resistor MRS25
R49 10K0 Resistor MRS25
R5 24R9 Resistor MRS25
R50 10K0 Resistor MRS25
R51 1R00 Resistor MRS25
R52 1R00 Resistor MRS25

27

SPHINX Project Two Mk2 Service Manual

Designator Part Type Description

R53 5K00 Resistor MRS25
R54 5K00 Resistor MRS25
R55 100K Resistor MRS25
R56 15K0 Resistor MRS25
R57 15K0 Resistor MRS25
R58 1R00 Resistor MRS25
R6 10R0 Resistor MRS25
R60 1R00 Resistor MRS25
R61 5K00 Resistor MRS25
R62 5K00 Resistor MRS25
R63 100K Resistor MRS25
R64 600R Resistor MRS25
R65 600R Resistor MRS25
R66 15K0 Resistor MRS25
R67 15K0 Resistor MRS25
R68 1R00 Resistor MRS25
R7 10R0 Resistor MRS25
R70 24R9 Resistor MRS25
R71 24R9 Resistor MRS25
R72 100R Resistor MRS25
R73 243R Resistor MRS25
R74 51R0 Resistor MRS25
R75 10R0 Resistor MRS25
R76 4K75 Resistor MRS25
R77 10R0 Resistor MRS25
R78 51R0 Resistor MRS25
R79 243R Resistor MRS25
R8 10R0 Resistor MRS25
R80 100R Resistor MRS25
R81 100R Resistor MRS25
R82 243R Resistor MRS25
R83 51R0 Resistor MRS25
R84 10R0 Resistor MRS25
R85 4K75 Resistor MRS25
R86 10R0 Resistor MRS25
R87 51R0 Resistor MRS25
R88 243R Resistor MRS25
R89 100R Resistor MRS25
R9 10R0 Resistor MRS25
R90 4K75 Resistor MRS25
R91 4K75 Resistor MRS25
R92 600R Resistor MRS25
R93 600R Resistor MRS25
R94 600R Resistor MRS25
R95 600R Resistor MRS25
R96 18R0 Resistor MRS25
R97 18R0 Resistor MRS25
R98 18R0 Resistor MRS25
R99 18R0 Resistor MRS25

28

SPHINX Project Two Mk2 Service Manual

Designator Part Type Description

RL1 Alcatel 24V MT2 DIL relay
RL2 Alcatel 24V MT2 DIL relay
RL3 Alcatel 24V MT2 DIL relay
RL4 Alcatel 24V MT2 DIL relay
RL5 Alcatel 24V MT2 DIL relay
RL6 Alcatel 24V MT2 DIL relay
RL7 Alcatel 24V MT2 DIL relay
RL8 Alcatel 24V MT2 DIL relay
RL9 Alcatel 24V MT2 DIL relay

SP1 SILPAD Soldering pad
SP2 SILPAD Soldering pad
SP3 SILPAD Soldering pad
SP4 SILPAD Soldering pad
SP5 SILPAD Soldering pad
SP6 SILPAD Soldering pad

T1 R-CORE 50VA SEC Transformer

T10 2SC3298 Transistor
T11 2SA1306 Transistor
T12 2SC3298 Transistor
T13 2SA1306 Transistor
T14 2SC2240 Transistor
T15 2SA1145 Transistor
T16 2SC2705 Transistor
T17 2SA1145 Transistor
T18 2SC2240 Transistor
T19 2SA1145 Transistor
T2 2SC3298 Transistor
T20 2SC2705 Transistor
T21 2SA1145 Transistor
T22 2SC2240 Transistor
T23 2SC2240 Transistor
T24 2SA970 Transistor
T25 2SJ109 Dual P-JFET
T26 2SK389 Dual N-JFET
T27 2SA970 Transistor
T28 2SJ109 Dual P-JFET
T29 2SK389 Dual N-JFET
T3 2SA1306 Transistor
T30 2SA970 Transistor
T31 2SC2240 Transistor
T32 2SA970 Transistor
T33 2SC2240 Transistor
T34 2SC2240 Transistor
T35 2SA970 Transistor
T36 2SC2240 Transistor
T37 2SA970 Transistor
T4 2SC3298 Transistor

29

SPHINX Project Two Mk2 Service Manual

Designator Part Type Description

T5 2SA1306 Transistor
T6 2SA970 Transistor
T7 2SC2240 Transistor
T8 2SA970 Transistor
T9 2SC2240 Transistor
U1 L7824C Voltage regulator

U2 OPA604AP IC
U3 OPA604AP IC
U4 OPA604AP IC
U5 OPA604AP IC

30

SPHINX Project Two Mk2 Service Manual

Partlist display

Designator Part Type Description

C1 47uF/16V Electrolytic capacitor
C2 470uF/25V Electrolytic capacitor
C3 100nF MKT capacitor
C4 100nF MKT capacitor
C5 33pF Ceramic capacitor
C6 100nF MKT capacitor
C7 33pF Ceramic capacitor
C8 100nF MKT capacitor
C9 100nF MKT capacitor

CN1 18PIN 18 pins header

IR1 SHARP GP1U5 Infrared receiver

LD1 LD2C LED
LD2 TLL46221C LED red
LD3 TLL46221C LED red
LD4 TLL46221C LED red
LD5 TLL46221C LED red
LD6 TLL46221C LED red
LD7 TLL46221C LED red
LD8 TLL46221C LED red
LD9 TLL46221C LED red

R1 5R62 Resistor MRS25
R10 390R Resistor MRS25
R11 390R Resistor MRS25
R2 61K9 Resistor MRS25
R3 390R Resistor MRS25
R4 10K Resistor MRS25
R5 39K2 Resistor MRS25
R6 10K Resistor MRS25
R7 10K Resistor MRS25
R8 390R Resistor MRS25
R9 10K Resistor MRS25

S1 ENCOJ-B24-AE0006 Switch
S2 ITW 60 1000 Switch
S3 ITW 60 1000 Switch
S4 ITW 60 1000 Switch

T1 2SC2240 Transistor
T2 2SA970 Transistor
T3 2SC2240 Transistor
T4 2SA970 Transistor
T5 2SC2240 Transistor
T6 2SA970 Transistor
T7 2SC2240 Transistor

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SPHINX Project Two Mk2 Service Manual

Designator Part Type Description

T8 2SA970 Transistor

U1 MC7805 IC
U2 ULN2804 IC
U3 H8/325 HD6413258CP10 IC
U4 8,00000MHz X-TAL
U5 MAX690 IC

©1998 Audioscript BV
Version: 2-09-98

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