SPL Iron V2 Two-Channel Tube Mastering Compressor (Black/Silver) - Manual (Page 9)

9
Technical Aspects
Signal Flow
The following diagram depicts the signal flow within the IRON compressor. It is meant to
clarify how it works and to show the relation between its different parameters. The audio
signal flow is in blue and the control voltage signal flow is in green.
RECTIFIER
12AU7
ECC82
12AX7
ECC83
Input Output
Output Gain
Sidechain Selection
Equalizer Input
Sidechain Send Sidechain Return
Equalizer Output
Attack Release
Input Gain Rectifier
Threshold Tube Bias
Air Bass /
Tape Roll-Off
Sharp Cut-Off Tube
Remote Cut-Off Tube
Opto Peak
Limiter Transformer Transformer
Cathode
Anode
Grid
Cathode
Anode
Grid
1
2
3 5 8
1
2
– + 0
ATTACK
fa
st
•
• • •
slo
w
fa
st
•
• • •
s
low
fa
st
•
• • •
s
low
RELEASE
THRESHOLD
min
2
4
6
8
10
12
1 4
18 2 0 2 2 24 26 2
8 30
3
2
34
36
38
40
m
ax
1m
F
2
mF
3
.3mF 330nF 22
0nF
10
0n
F
Ge
Ge
LED Si
Ge
Ge
/S
i
Perkin Elmer
VTL 5C1
2
4
6 8 10
12
INPUT
– + 0
O
FF
EQ
1
EQ 2 EQ 3 EQ
4
EX
T.
SID
E CHAIN EQs
TUBE BIAS
Low
Mid
High
AirBass
Tape Roll-Off
OUTPUT
External Equalizer
Audio
Control voltage
higher bias =
higher Gain
reduction