172.248, 172.249 User Manual
With mixer (or other signal source) levels turned down, gradually increase the amplifier’s channel level controls to the
required level (normally full) and then gradually increase the signal level from the mixer or sound source until sound can
be heard through the speakers and then continue increasing up to the required level.
During use, green “SIGNAL” LEDs will illuminate to show when a signal is present and red LED “CLIP” LEDs illuminate if
the output is reaching clip level. If the red CLIP LEDs illuminate more than very briefly, reduce the volume until they
hardly light up at all.
If the internal protection circuitry detects a fault in the speakers or amp, the channel(s) will enter Protect Mode and red
“PROTECT” LEDs will illuminate on the front panel to show this. Switch the amplifier off and check the entire system
(including leads) before powering up again. If still in Protect Mode, seek advice from qualified service personnel.
Before powering down, turn the channel gain controls fully down to avoid loud noises when switching off.
Specifications
Model
P44800
P551000
Power supply
240Vac 50Hz (IEC)
CH1 and CH2 power RMS @ 8
Ω
2 x 250W
2 x 350W
SUB power RMS @ 8
Ω
500W
700W
CH1 and CH2 power RMS @ 4
Ω
2 x 400W
2 x 550W
SUB power RMS @ 4
Ω
800W
1000W
Input : Line
3 x XLRF + 6.3mm jack
Input impedance (bal/unbal)
40k Ohms / 20k Ohms
Frequency response
10Hz - 50kHz (-2dB)
SUB filter cutoff frequency
50Hz - 250Hz
THD + N
0.04%
Slew rate
6.5V/usec
S/N ratio
-86dBm
Controls
3 x channel level, LOW CUT on/off, FILTER on/off, FREQ
Speaker outputs
CH1, CH2 and SUB SPK connectors
Circuit protection
Short-circuit, DC, overload, soft-start
Dimensions
483 x 439 x 88mm
Weight
21kg
23kg
Troubleshooting
No power light on front panel switch
Ensure IEC inlet is connected to mains and lead is in good condition
Ensure mains outlet is switched on
Power light is on but no other LEDs and no
output
Check input signal and connection leads
Ensure channel gain controls are not turned fully down
Power light and Signal LEDs are lit but no
output
Check speaker cabinets are in good working order
Check speaker leads are in good condition and connected properly
“PM” (Protect Mode) LED is lit and there is
no output
Switch off and disconnect from mains
Check speakers are in good working order and not shorted out (using a multi-tester)
After checking all connected items, power up again
If still in Protect Mode, switch off again and refer to qualified service personnel
Ensure cooling vents are clear and amplifier is not overheated
SUB output has “muffled” mid frequencies
Switch on FILTER and adjust FREQ control for subs that have no built-in crossovers
SUB output has quiet output with FILTER
on
If FREQ is set too low, there may be quiet output, adjust the control to improve output
Switch off FILTER for better output to subs with built-in crossovers
Output is very distorted and “CLIP” LEDs
are lighting
Check the speaker impedance is not below 4 Ohms per channel
Turn down the input level from audio source
Turn down channel gain controls
Output is working but at very low level
Ensure input source is at line level
Increase input level from audio source
Turn up channel gain controls
Errors and omissions excepted.
Copyright© 2013. AVSL Group Ltd.
