GOD CITY INSTRUMENTS Socialist Jr. V1.1 User manual

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GOD$CITY$INSTRUMENTS$–$Socialist$Jr.$V1.1$Build$guide$
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Part
Value
Description
Subsititute
Substitution Notes
C1
2.2u
electrolytic cap
1u-4.7u
Forms HPF with R13. Bigger = more bass/mud.
C2
0.1u
MLCC
C3
2.2n
film cap
1n-4.7n
Forms input LPF with R1. Bbigger = mud, smaller = possible RF.
C4
22n
film cap
C5
100u
electrolytic cap
47u-220u
power filter cap
C6
100u
electrolytic cap
47u-220u
power filter cap
C7
10u
electrolytic cap
4.7u-22u
Forms HPF with R16. Bigger = more bass/mud.
C8
1n
MLCC
680p-2.2n
Smooths high frequencies related to clipping of ssecond stage.
C9
47n
film cap
C10
27n
film cap
C11
300p
MLCC
C12
0.22u
film cap
C13
1n
film cap
470p-2.2n
Switchable system LPF
C14
270p
film cap
100p-470p
System LPF
C15
1.5u
film cap
1u-2.2u
Forms HPF with R15 and Response. Bigger = more mud.
C16
0.1u
film cap
C17
1u
film cap
C18
1u
film cap
C19
120p
MLCC
47p-470p
Smooths high frequencies related to clipping of first stage.
C20
470p
MLCC
C21
270p
MLCC
D2
Yellow
3mm LED
D3
1n4148
Si diode
D4
1n4148
Si diode
D6
1n34a
Ge diode
D7
1n5818
Scottky diode
1n5817, 1n4001
Any suitable polarity protection diode
LED
L1
LED
IC1
MC1458
dual op amp
TL072, TLC2272, LM833
Pin compatible dual op amp
IC2
TL072
dual op amp
TLC2272, NE5532, OPA2132
Pin compatible dual op amp
CLR
4.7k
1/4 watt resistor
R1
1k
1/4 watt resistor
R2
2.2M
1/4 watt resistor
R3
10k
1/4 watt resistor
R4
10k
1/4 watt resistor
R5
1M
1/4 watt resistor
R6
2.2M
1/4 watt resistor
R7
10k
1/4 watt resistor
R8
1k
1/4 watt resistor
R9
10k
1/4 watt resistor
R10
22k
1/4 watt resistor
R11
120k
1/4 watt resistor
68k-180k
Affects mid frequency. Lower value = lower frequency.
R12
100k
1/4 watt resistor
4.7k-33k
Affects output volume. Smaller = more volume. May cause clipping

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R13
1k
1/4 watt resistor
470R-3.3k
Affects gain and bass in 2nd stage. Smaller = brighter and gainier.
R14
1k
1/4 watt resistor
R15
100R
1/4 watt resistor
R16
2.2k
1/4 watt resistor
R17
10k
1/4 watt resistor
R18
2.2k
1/4 watt resistor
R19
100k
1/4 watt resistor
12k-220k
Affects output volume. Bigger = more volume. May cause clipping
R20
12k
1/4 watt resistor
R21
10R
1/4 watt resistor
CLIP
SPDT.PINS
on/off/on
3 position switch!
MID
DPDT.PINS
on/on
2 position switch!
DARK
SPDT.PINS
on/on
3 position switch!
DISTORTION
B10k
DUALGANG 16mm pot
RESPONSE
C1k
16mm pot
LOUDNESS
B1M
16mm pot
LEVEL
A100k
16mm pot
S
PAD
send to PCB
L+
PAD
LED+
L-
PAD
LED-
R
PAD
return from PCB
V
PAD
9V input
G
PAD
ground
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0 0.400 1.200 0.400 1.200
0
0.800
1.275
1.750
3.955
0
0.875
0
0.875