8

9

10

11

 

 

THERMAL

OL

SIGNAL POWER

OUTPUTS

 

 

 

 

 

 

 

 

 

A

HIGH PASS

B

 

LEVEL

 

 

 

 

 

7

6

5

-6dB +6dB

POLARITY

A

FULL RANGE

B

 

NORMAL

4

INVERT

 

INPUTS

AB

3

7. LEVEL

9. OL LED

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].

8. THERMAL LED

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.

10. SIGNAL LED

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.

11. POWER LED

This LED illuminates when the power switch [2] is turned on and the linecord is connected to an active AC Mains supply.

10