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9. INPUT
This is a female XLR connector, which accepts a XLR plug from almost any type of equipment with a balanced or
unbalanced outputs. The XLR input is wired as follows:
Pin 1 = shield or ground
Pin 2 = + positive or "hot"
Pin 3 = - negative or "cold"
When connecting an unbalanced signal, wire them as follows:
Pin2 = + positive or "hot"
Pin 1-3 = shield or ground
NOTE:
whenever possible, use always balanced cables. Unbalanced lines may also be used but may result in noise over
long cable runs. In any case, avoid using a balanced cable for one channel and an unbalanced one for the other.
10. LINK
This is a male XLR connector, it is connected in parallel with the respective INPUT, so the LINK is wired at the same
way.
11. STEREO / PARALLEL
/ BRIDGE
Allows the selection of STEREO, PARALLEL or BRIDGE mode operations.
• In STEREO mode each amplifier channel pair runs independently driven by respective input (see EXAMPLE A).
• In PARALLEL mode both amplifier channels pair run together driven by Channel 1 input (see EXAMPLE A, D).
NOTE:
use this setting if your intention is to use the BI-AMP feature also.
• In BRIDGE mode the amplifier channels pair runs together but with channel 1 in phase and channel 2 out of phase.
The channels pairs are driven by Channel 1 input and the output must be taken from "OUTPUT 1" speakon output
(see EXAMPLE B, C).
IMPORTANT:
In this case a custom cable must be used wired as follows: at the amplifier side it must be wired 1+
for positive terminal and 2- for the negative terminal, at the speaker side the cable must be wired as usual 1+ for
positive terminal and 1- for the negative terminal.
12. HPF / BI-AMP / FLAT
This switch allows the selection of one of the following filter configurations:
• HPF: enables a 100Hz LR-24dB/Oct. High Pass Filter for both channels 1 and 2: this a useful feature for SAT-TOP
SPEAKERS or STAGE-MONITORS (see EXAMPLE B).
• BI-AMP: enables a Linkwitz-Riley crossover 24dB/Oct. at 100Hz between channel 1 and channel 2, then allows a single
amplifier without a dedicated processor to drive a SUB-WOOFER with channel 1 and a SAT-TOP SPEAKER with channel
2 (see EXAMPLE C, D).
• FLAT: no filters are inserted in the signal path (see EXAMPLE A).
13. Channel 1 SPEAKON output
Accepts a male Neutrik Speakon NL4FX connector wired in this way:
• PIN 1+ connected to POSITIVE output of Channel 1;
• PIN 1- connected to NEGATIVE output of Channel 1;
• PIN 2+ connected to POSITIVE output of Channel 2,
• PIN 2- connected to NEGATIVE output of Channel 2,
If you connect a standard 2 wire cable (1+/1-), you run to the speaker the amplified output of the signal applied to
channel 1 input.
If you connect a standard 4 wire cable (1+/1-/2+/2-), you run to the speaker:
• with amplifier set in STEREO mode, the amplified outputs of the signal applied to channel 1 input (1+/1-) and to
channel 2 input (2+/2-),
• with amplifier set in PARALLEL mode, the amplified outputs of the signal applied to channel 1 input only, (1+/1-) =
(2+/2-),
In both modes using a single cable you can connect a BI-AMP loudspeaker or a SUB-SAT speaker system.
Always connect a loudspeaker with a minimum impedance of 4 ohm or more.
• With amplifier set in BRIDGE mode, you run to the speaker the amplified output of the signal applied to channel
1 input only, but the speakon cable must be custom wired as follows: at the amplifier side it must be wired 1+
for positive terminal and 2- for the negative terminal, at the speaker side the cable must be wired as usual 1+ for
positive terminal and 1- for the negative terminal.
Always connect a loudspeaker with a minimum impedance of 8 ohm or more.
