Solid State Logic Super-Analogue Outboard X-Rack E Series - Manual (Page 3)

Page K-1
X-Rack E Series EQ Module
K. E Series EQ Module
K.1 Connection
The module input and output gains can be set to operate at a nominal level of either
+4dBu or –10dBV, using a switch on the connector panel. To select the appropriate
level for the equipment you are connecting to, please check the operating manual for
your mixer or DAW. The switch should be released for +4dBu operation: push it in for
–10dBV operation.
K.2 Operation
The X-Rack E Series EQ module is a re-implementation of two of the classic SSL EQ
circuits. The module defaults to the original ‘Brown Knob’ circuit that was standard
on all early production E Series consoles but can be switched to emulate the later
‘Black Knob’ circuit.
The BLK button
switches the module from the default ‘Brown Knob’ EQ to
‘Black Knob’ EQ.
The IN button
switches the entire section in and out of circuit.
K.2.1 ‘Brown Knob’ EQ
With the BLK button out, the two parametric mid-band sections feature SSL’s classic
logarithmically symmetric design that ensures that the ±3dB up/down points retain
the same musical interval from the centre frequency regardless of frequency and
amplitude settings. The two shelving sections are traditional 6dB/octave designs
with an option for a fixed Q parametric response (Bell). The ‘02’ EQ, to give it its
correct name, was used on countless recordings and mixes in the early eighties.
K.2.2 ‘Black Knob’ EQ
In 1983 a new ‘242’ EQ circuit was developed in conjunction with the legendary
George Martin for the first SSL console to be installed in AIR studios. The ‘Black
Knob’ EQ, as it became known, featured enhanced cut and boost ranges (±18dB
instead of ±15dB) together with a different control law and a steeper 18dB/octave
high pass filter for tighter control of low frequencies. It is this design which is
retained today as the ‘E Series’ EQ option of the AWS 900 and Duality consoles. It is
also to be found in use in the X-Rack XR625 EQ module which features this design
alongside an implementation of the ‘G Series’ EQ.
2
1
SEL
IN
XR425
HF dB
HMF
LMF
dB
dB
Q
Q
- +
- +
- +
BLK
KHz
KHz
16 1.5
10 5
2 14
7 .6
4.5 1.5
.8 6
KHz
2.5 .2
1.5 .8
.3 2.0
BELL
LF dB
- +
Hz
450 30
300
50
BELL
OUT
IN
+4dBu
-10dBV
1
2