Dynacord CL 1200 User Manual

POWER-indicator not lighting are: the appliance is not connected to the mains 

or the primary fuse is defective. 

The PROTECT LED indicating that one of the internal protection circuits 

against thermal overload, short-circuit, Back-EMF, RF-occurrence at the output, 

etc., has been activated. The output relays interrupt the connected loads from    

the power amps while input signals are interrupted as well, preventing the connected 

loudspeaker systems and the power amplifi ers themselves from being damaged.

Whatever caused the fault – e.g. a short-circuited speaker cable – needs to be reme-

died. In case of thermal overload you have to wait until the power amplifi er automati-

cally regains normal operation.

The SIGNAL LED lights as soon as an audio signal of approximately 30dB below full 

modulation is present at the output. The LED is dimmed when speaker cables are 

short-circuited or a protection circuit has been activated.

The 0dB LED lights whenever the power amplifi er is driven at its maximum. Higher 

input voltage does not result in higher peak output voltage. In addition, the 0dB 

indicator comes in handy when adjusting external limiters.

This indicator lights as soon as the integrated dynamic audio signal limiter is 

activated and the power amplifi er is driven at the clipping limit or generally at its 

maximum capacity. Short-term blinking is not a problem, because the internal limiter 

controlls input levels of up to +21dBu down to a THD of approximately 1%. If, on the 

other hand, this LED lights constantly, reducing the volume is recommended to 

prevent the loudspeaker systems connected from being damaged by probable 

overload.

Detent potentiometers scaled in dB (steps of 1dB) for 

adjusting the power amp’s overall volume. To prevent 

distortion in mixing consoles connected to your CL-Series 

amp, setting these controls to a value between 0dB and -6dB 

is generally recommended. The dB-scale provides direct 

indication of the control attenuation applied to the fi xed 

 

 

 

 

internal amplifi cation.

Use the 

POWER switch, located on the front panel’s, right side to switch the appliance’s power on. The 

soft-start function limits against current inrush peaks on the mains, which in addition prevents the mains 

line protection switch from activating during power-on. The loudspeaker outputs are activated via relay 

switching with a delay of approximately 2 seconds to effi ciently attenuate eventual power-on noise. The 

PROTECT LED lights during the delay time and the fans run at maximum speed. This is normal, con-

fi rming the correct operation of the protection circuitry. 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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