dbx 20 Serie Modo De Empleo página 9

20 SERIES GRAPHIC EQUALIZERS
2215 - dual channel 15 band graphic equalizer
Power Cord Receptacle: Connects AC power to the equalizer.
Power Switch: Switches the power on and off. Always make audio connections with the power switch in the OFF
position.
Input Connectors: Three types of input connectors are provided for input connections: female locking XLR type
connectors, 1/4" tip-ring-sleeve phone jack connectors, and a barrier strip. The maximum input level that the equal-
izer can accept is +22dBu (ref: 0.775Vrms).
Output Connectors: Three types of output connectors are provided for output connections: male XLR type con-
nectors, 1/4" tip-ring-sleeve phone jack connectors and a barrier strip.
Chassis Ground Lift Strap: By removing the jumper connecting the two screws on the barrier strip, the chassis
ground is separated from the circuit ground of the equalizer. This is sometimes necessary to prevent "ground loops"
in a sound system. When lifting the ground strap, you must make a connection from the circuit ground ( ) terminal
to some other ground point in your audio system in order for the equalizer to function properly.
to system
ground
Output
Cable
I
NSTALLATION
Hookups and Cabling: The 20 Series Equalizers are designed for nominal +4dBu levels. The equalizers 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 40kΩ balanced and 20kΩ unbalanced. This
makes the 20 Series Equalizers' audio inputs suitable for use with virtually any low source impedance (under 2kΩ).
Output Cable Configurations: The equalizer's output is capable of driving a 600Ω load to +18dBu. For maximum
hum rejection with a balanced source, avoid common grounding at the equalizer's inputs and outputs. Most bal-
anced (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.
Wiring Connections With Ground
WIRING CONNECTIONS WITH GROUND
Without Jumper in Place
circuit chassis
ground ground
+ +
+
+
Input
optional
Cable
C
ONSIDERATIONS
OPERATION MANUAL
With Jumper in Place
circuit chassis
ground ground
+ +
+
+
Output
optional
Cable
jumper
Input
Cable
5