Great River Electronics 32EQ - Manual

20
8 .4
.16
H/LP
IN
.03 2.5
.05 1.3
10
10
10
10
4
4
4
4
0
0
0
0
4
4
4
4
10
10
10
10
LO-MID
HI-MID
LOW
HI
EQ
IN
.04 .7
.08 .3
.15
.2 4
.4 1.5
.85
.4 6
.9 3
1.8
.8 14
2 6
4
! -3
.25
HP
LP
2
Harrison 32EQ
The Harrison 32EQ is a parametric, four band equalizer of proprietary design with a design history going back to
the highly respected Harrison Consoles. This 500 series module also includes the parametric, second order
high-pass and low-pass filters made famous in the 32 series consoles.
The proprietary design of the equalization stages allows full reciprocal operation of the boost/cut controls both
as to frequency and to phase response. Special circuitry automatically adjusts the effective bandwidth under
all conditions. Continuously variable frequency selection and boost or cut amount provides proper equalization
for almost any desired effect.
The high band “HI” extends from 800 Hz to 16 kHz. The two mid-ranges “MID” are overlapping; one extends
from 400 Hz to 8 kHz while the other goes from 200 Hz to 4 kHz. The low range “LO” covers 40 Hz to 800 Hz.
Additionally, the low and high ranges are selectable to be either shelving or peaking. The mid-ranges are peaking.
There is an in/out “IN” switch for the four bands of boost/cut equalization.
The parametric high-pass and low-pass filters have 12dB per octave cut off characteristics. They are of an all
electronic design, and contain no inductors. The high-pass filter has a range of 25 Hz to 2.75 kHz and the
low-pass filter extends from 160 Hz to 20 kHz. Continuously variable “HP” and “LP” controls allow both subtle
corrections as well as special effects. There is a separate “in” switch for the filters so that they can be inserted
into the signal path independently of the equalizer.
The equalizer is a unity gain design, delivering excellent noise and headroom performance.
E L E C T R O N I C S
All references to Harrison and their logo are with written permission from Harrison Consoles Inc.
High frequency shelf out, peak in
High and low pass enable, in
EQ sections enable in
Low frequency shelf out, peak in
Low pass filter control
High pass filter control
Low frequency select
Low frequency boost / cut
Low mid frequency boost / cut
High mid frequency boost / cut
High frequency boost / cut
Low mid frequency select
High mid frequency select
High frequency select