Pax 6550 schematic

10 ohms

10W

standby

P.T.

power switch

fuse

16ohms

8ohms

10k

feedback

OT

25

10 ohms

PLATE

200uf

EL 84

7

2

3

4 5

130

9

100

EL 84

100

.068

EL 84

25

EL 84

130

100

100

10k 10k

180wv

.033

diode
1n4007

200uf
180wv

SCREEN

1n4007

200ohms

20+20+

5,

1k

4,

20uf

7k

10W

350wv

25k

10uf

130v

6,3v to power filaments

6,3v to pre filaments

47k

hum

ac

adj

115v

ac

light

100k

.

Power transformer input (
(

115vac

parallel)

230Vac

series)

CH1

CH2

10k

10k

25k

7

.047

4,

.0022

.022

.022

7k

10k

.022

VOLUME

B

CH2

1M

300pf

47k

.001

Treble

1M

B

6AV6

1

5

2

.001

10k

7

3 4

Bass

1M

B

1,

5k

6

33

.022

220

.0022

.022

10k

BIAS
1M

47

6AQ8

220

33

300pf

VOLUME

CH1

1M

B

10k

1

6

7

3

--------------

4

9

8

25k

1k
100pf

PAX

INSTRUMENT AMPLIFIER

MODEL 6550

47k

MADE IN JAPAN
MAYBE IN THE 60'S

6,

3v

power tube filament to

6.3v

preamp

tube filament to

preamp

filament is polarized to the ground by hum adjustment.(

EL84

6AQ8

pin 4 and ,

pin 4 and 5,

6AV6

pin 3 and 4(one is to ground)

12AX7

pin 9 and other both 4,5

adj

coil 100 ohms DC)

25k

12AX7

1

6

4,

7k

4,

4,

7k

7k

.047

4,

7k

4,

7k

.001

Treble

1M

B

2 2

10k

.001

3

4

9

8

5 5

Bass

1M

B

1,

5k