8
AC Mains
Connect AC power to the IEC socket on the back of the amplifier by locating 
the IEC connector-end of the AC power cord and inserting it fully into the IEC 
inlet on the power amplifier module. NOTE: Turn off the AC power switch 
before connecting AC power.
An AC power cord hook-and-loop tether (retention strap) is provided to mini-
mize the risk of the power cord being inadvertently pulled from its connection 
at the back of the amplifier. To use the tether, pass it through the chassis 
lance (adjacent the IEC socket) and then capture the AC power cord by loop-
ing it in the tether before closing the hook-and-loop strap. 
The correct AC line voltage is shown on the serial number label, on 
the rear panel. Connecting to the wrong line voltage may damage the 
amplifier or increase the risk of electric shock.
AC Mains Disconnection
Turn the AC power switch to the off position. To remove the AC mains cord, 
grasp the IEC connector’s plastic body and pull, removing the connector from 
the socket. 
Power Switch
Push in on the top of the rocker switch to apply AC mains power to the pow-
ered loudspeaker. Push in on the bottom of the rocker switch to turn the pow-
ered loudspeaker off.
When turned on, the blue POWER indicator LED and the red LIMIT (limiter) 
indicator LED will illuminate; after a few seconds the red LIMIT indicator will 
extinguish.
LED POWER Indicator
The blue LED POWER indicator will illuminate when the AC Power switch is 
in the “ON” position, the AC mains power cord is connected properly, and the 
AC mains are functioning properly. The LED POWER indicator will extinguish 
when the AC Power switch is in the “off” position or AC mains power has 
been removed from the loudspeaker.
If the POWER indicator does not illuminate when the Power switch is placed 
in the “on” position, verify the AC mains line cord is properly attached to the 
loudspeaker and plugged into the AC outlet. Verify the outlet is functioning 
properly. 
If the AC mains cordset is serviceable and the AC mains outlet is oper-
ating properly, but the loudspeaker fails to operate, the loudspeaker 
may require servicing. Contact QSC’s Technical Services department.
System Power Sequencing
Proper power turn on sequence can help to prevent unexpected sounds from 
your system (pops, clicks, thumps). These unintended sounds can damage 
drivers and cause audience members to question the professionalism of the 
sound team. Turn on and off the system in the proper order to avoid unex-
pected sounds. 
Power On Sequence: Turn on all source devices (CD players, mixers), turn 
on subwoofer, then turn on the “top-boxes” (HPR122i, HPR152i and HPR153i).
Power Off Sequence: Turn off the top-boxes, turn off the subwoofer, then 
turn off the source devices.
AC power switch
Power “on” indicator LED
AC power cord 
tether use-
1- Insert tether 
through chassis 
lance adjacent IEC 
inlet.
2- Form a small 
loop in the AC 
power cord. Cap-
ture the AC power 
cord in the tether 
and secure by pull-
ing the smaller end 
through the hole in 
the tether’s large 
end.