Crown Audio CTS4200A Manual De Usuario

NOTE: For detailed information about 
these Crown amplifi er features, please 
consult the Crown Amplifi er Application 
Guide, available on the Crown website 
at www.crownaudio.com

Your Crown amplifi er provides extensive 
pro tection and diagnostic capabilities, 
including thermal level control, fault indicators, 
high-pass fi ltering, DC protect, AC under/over 
volt age protection, inrush limiting, and 
variable-speed fans.

If the amplifi er becomes too hot for safe 
opera tion, the light will shine brightly and TLC 
will engage the input compressor. By 
compressing the input, the amplifi er will not 
generate as much heat and will have a chance to 
cool down. The degree of compression is 
proportional to the amount of overheating. This 
feature allows the show to go on, rather than 
having the amplifi er shut down.

JTS circuitry simulates the operation of the 
amplifi er’s output transistors, and compares it 
against the transistors known Safe Operation 
Area (SOA). If  JTS sees that more power is 
about to be asked of the output devices than 
they are capable of delivering under the present 
conditions, JTS immediately limits the drive 
level until it falls within the SOA. Limiting is 
proportional and kept to an absolute minimum-
only what is required to prevent the possibility 
of output transistor damage.

This level of protection enables Crown to 
increase output transistor utilization while also 
greatly increasing amplifi er reliability.

The amplifi er will light the Fault LED if the 
amplifi er output stage stops operating.  If this 
happens, see Section 8 for servicing 
informa tion.

Very low frequency signals contain no useful 
musical energy, waste valuable amplifi er power 
and headroom, and can be damaging to your 
speakers. Your Crown amplifi er provides high-
pass fi lters to remove these signals from each 
channel’s output.

On the back panel are two 3-position 3rd-order 
high-pass fi lter switches (one per channel) with 
selections of Off, 35Hz and 70 Hz.

Gaussian-approximation ultrasonic fi lters 
pre vent ultrasonic feedback and HF burnout in 
drivers. This type of fi lter preserves transient 
response better than a Butterworth fi lter.

If the AC line voltage drops below 25% or rises 
above 15% of the nominal operating voltage of 
the amplifi er, the amplifi er’s power supply turns 
off and the blue Power LED fl ashes. The 
ampli fi er will turn back on when the AC line 
voltage returns to safe operating levels (within 
+15% / -25%). 

A circuit breaker located near the IEC power 
inlet protects the amplifi er from excessive AC 
current draw.

The output servo circuit protects your drivers by 
eliminating DC offset, even in the presence of 
very large asymmetrical signals.

A soft-start circuit in the power supply 
mini mizes the amplifi er’s current draw during 
power-on.

Two continuously variable speed fans direct the 
airfl ow through the amplifi er for cooling.

Crown’s Switching Power Supply minimizes the 
amplifi er’s weight.

Typical non-switching power supplies require 
large, heavy transformers in order to produce 
the required power at the output stage. These 
transformers must be large to operate at 50 to 
60 Hz (standard AC supplied by the power 
company).

By contrast, switching power supplies can 
operate with a much smaller (and lighter) 
trans former because they fi rst convert the AC up 
to a much higher frequency, thereby reducing 
waste. 

The power supply is voltage-specifi c, allowing 
use in regions using 120V or 240V.  

Prevent input/output overload.

Lowers standby power consumption by shut ting 
down the high-voltage supplies during idle 
periods.

NOTE: By default, the sleep circuit is not active 
on the CTs 600/1200, but may be activated as a 
service option.