Crown 1160ma Guía Del Usuario

For the sake of simplicity, only channel one of 
the audio signal path is described.

Signal is presented to the CH4/CL4 through 
one of three connectors when using the stan-
dard input module. Each channel is outfitted 
with a balanced XLR/phone jack, and a barrier 
strip. These connectors are wired in parallel, 
which allows daisy chaining when needed. The 
signal is then converted from balanced to 
unbalanced in the Balanced Input Stage where 
it also receives RFI protection. Signal then 
flows into the Variable Gain Stage where the 
front panel level controls are allowed to affect 
the gain.

Following this stage, the signal goes through a 
gain stage that allows for the various positions 
of the sensitivity settings. The signal is then put 
under the control of a full-time compressor cir-
cuit comprised of a symmetrical window detec-
tor, a buffer amplifier, and the gating op amp 
which uses several small components to set the 
compressor’s attack and decay characteristics. 
The actual compressing is accomplished by an 
opto-isolator that affects the gain in the signal 
path.

Next, the signal enters a 32-kHz 7th-Order 
Gaussian Low-Pass Filter. This filter prevents 
the modulator stage and the output filter (both 
described below) from receiving signals that 
are too high. Without the 32-kHz filter, the 
modulator would be unable to process signals 
that are too high and the output filter would not 

yield the proper frequency response behavior. 
The Gaussian filter type is unique in that it has 
minimal ringing and excellent phase response 
so even a high-order filter such as this one 
does not adversely affect the sonic excellence 
of the product. 

In the CH4, the signal then travels either 
through the HP filter module or is bypassed 
around it depending on the position of the 
channel operation switch. With the switch set in 
the 70V position, the filter is enabled. The filter 
is an 18 dB-per-octave high-pass with a –3-dB 
rolloff at 70 Hz. This provides a measure of 
protection to step-down transformers used in 
distributed speakers installations. With the 
switch set in the 4/8-Ohm setting, the filter is 
bypassed. The power is delivered to the load 
cables through the output connector panel 
which consists of one of several options.