DAD PX Series, User Manual

11

Reliability - Protection function

This amplifier has many protecting functions that give to this product a great reliability. 
These protections prevent damages either to amplifier or to loudspeakers.

1. Clip / limiter
    When the amplifier output appears to be clipped, to avoid damages to the speakers, a built-in
    clip/limiter automatically limits too high input signals. This function can be activated by the switch 
    placed on the amplifier’s rear panel 

(

and only)

2. Over-heat protection  
    This equipment works at a rated temperature range 

(

see page 15). If the environment’s temperature 

    exceeds the rated values or  the user employment is not correct, it will cause an internal temperature 
    increase. In this case, output power is automatically limited until the temperature will be again into its
    normal range values. 

3. VHF protection 

(

and only)

    If a non-musical signal, exceeding audio range, occurs in the input, the amplifier will limit output power
    to protect itself and the speakers. Normal output power will be automatically recovered when the VHF 
    signal is cut off.
 
4. Short-circuit protection
    When a short-circuit occurs on the amplifier’s output 

(

protection limit is below 1 ohm), the amplifier 

    will limit its output power. It will be automatically recovered as soon as the short-circuit is 
    removed.

5. VLF protection 
    If a continuous long-period non-musical signal 

(

VLF), occurs in the input, the amplifier will 

    automatically attenuate the input signal and limit the output power in order to protect itself
    and the speakers. Normal output power will be automatically recovered when the VLF 
    signal is cut off.

6. DC protection 
    If the output signal exceeds a rated DC voltage, an output protection function disconnects the load,
    to protect the speakers.

7. Automatic “Fade-in” function
    When the amplifier starts up or automatically restarts up in consequence of a protection releasing, 
    the amplifier output level will grow gradually, either to protect the amplifier and speakesr or to allow 
    the ears’ adaptation.

Factory Settings

1. All volume control was set at "-80" ;
2. Grounding switch was set at "ON" ;
3. Working mode was set at "STEREO" .
4. Sensitivity switch was set at "0.775V .
5. Limiter switch was set at "ON" .
6. Low-pass switch was set at "OFF" . 

(

and only)

7. High-pass switch was set at "OFF" .