Specifications are subject to change without notice
AtlasSound.com
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©2006 ATLAS SOUND LP
Printed in USA
ATS002536 RevA 10/06
PP
OWNER'S MANUAL
EQM131 31 BAND GRAPHIC EQUALIZER
8
INSTALLATION CONSIDERATIONS
Hook-ups and Cabling:
The EQM131 Equalizer is designed for n4dBu levels.
The equalizer can be used with either balanced or unbalanced sources, and the outputs can be used with either
balanced or unbalanced loads, provided the proper cabling is used. A balanced line is defined as two-conductor
shielded cable with the two center conductors carrying the same signal but of opposite polarity when referenced to
ground. An unbalanced line is generally a single-conductor shielded cable with the center conductor carrying the
signal and the shield at ground potential.
Input Cable Configurations:
The equalizer has an input impedance of 20k
Ω
balanced and 15k
Ω
unbalanced. This
makes the EQM131 Equalizer’s audio inputs suitable for use with virtually any low source impedance (under 2k
Ω
).
Output Cable Configurations:
The equalizer’s output is capable of driving a 2k
Ω
load to +18dBu. For maximum hum
rejection with a balanced source, avoid common grounding at the equalizer’s inputs and outputs. Most balanced (3-
conductor) cables have the shield connected at both ends. This can result in ground loops which cause hum. If hum
persists try disconnecting the shield on one or more of the cables in the system, preferably at the input of a device,
not at the output.
TIP
(HOT)
RING
(COLD)
SLEEVE
(GND)
TIP
RING
SLEEVE
1/4" TRS CONNECTOR
(BALANCED)
TIP
(HOT)
SLEEVE
(GND)
TIP
SLEEVE
1/4" TS CONNECTOR
(UNBALANCED)
RCA CONNECTOR
(UNBALANCED)
TIP
(HOT)
SLEEVE
(GND)
2
1
3
1 - GROUND / SHIELD
2 - HOT
3 - COLD
1
2
3
OUTPUT
INPUT
XLR CONNECTOR
(BALANCED)
