Mackie SRM1801 Benutzerhandbuch

10

The LEVEL control adjusts the overall signal level at 

the input to the built-in power amplifier. It ranges from 
-6 dB to +6 dB (maximum gain), with unity gain at the 
center position (12 o’clock).

The control has no effect on the level of the high-

pass outputs [5] or the full-range outputs [4].

The SRM1801 is equipped with a thermal protection 

circuit that monitors the internal temperature of the 
amplifiers and heatsink. If the temperature exceeds a 
safe operating level, this indicator lights and the input 
signal is muted to allow the amplifiers to cool. When 
the temperature cools to a safe level once again, the 
thermal protection circuit deactivates, the Thermal 
LED turns off and the SRM1801 returns to normal 
operation. 

When the SRM1801 is in thermal protect mode, the 

power LED [11] will remain lit, indicating that the unit 
is still powered on despite the lack of output.  

Activation of the thermal protection circuit 
is an indication that you should take steps 
to avoid continued thermal problems. See 
“Thermal Protection” on page 12.

The OL (overload) indicator lights when the 

amplifier in the SRM1801 is near the clipping point. It 
is okay if the OL indicator blinks occasionally, because 
this means that the transient peaks are just reaching 
the maximum output of the amplifier and you are 
getting the most from your SRM1801. 

If the OL indicator is blinking frequently or lighting 

continuously, turn down the LEVEL control [7] on the
SRM1801 or turn down the signal at it source  
(e.g., the mixing console) until the OL indicator blinks 
occasionally or not at all.

This LED illuminates green whenever there is a 

signal present at the main input connector. It senses the 
signal just after the Level control, so adjustments to the 
level control will affect the signal indicator.  

This LED illuminates when the power switch [2] is 

turned on and the linecord is connected to an active AC  
Mains supply.