Input Signal Sensitivity; Ground-Lift - inout HA4V-R User Manual

HA4V-R User Manual v.1.0
3.3 Input sensitivity
The amplifier has a circuit inside that allows selecting a different sensitivity for the audio
signal incoming to accept low output signal sources.
To enable a different sensitivity remove the cover and set the jumpers as shown in the
following picture.
IMPORTANT:
use both jumpers for each channel.
INPUT SIGNAL SENSITIVITY SETTING
WITHOUT JUMPER = -5,7dBu
WITH JUMPER =+3,8dBu
(DEFAULT)
CH1 = JP1 – JP2
CH2 = JP3 – JP4
CH3 = JP5 – JP6
CH4 = JP7 – JP8

3.4 GROUND-LIFT

If there is low frequencies noise on the speakers due to ground loops, it's advisable to set JP9
jumper to OPEN position; that means to split audio ground from chassis ground.
GROUND LIFT CONFIGURATION
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