McIntosh C33 Owner's Manual page 16

(usually between 1.2 and 1.5). Now switch the ex-
pander on and off. A change in the average listening
level will usually be heard at this time. Adjust the
LEVEL MATCH control until the average listening
level matches as closely as possible when the ex-
pander is on and off. After this adjustment you will
notice that with the expander on, loud passages will
be louder and soft passages including noise will be
softer.
When the RATIO control is at the fully clockwise
position it corresponds to a ratio of 2.0. The output
dynamic range is then twice the input dynamic range.
This setting is usually too high for most program
material.
Two examples for using the expander are as
follows.
1. To reduce background noise (hum, hiss or
scratch):
a. Select the desired program source with the
LISTEN input selector.
b. Increase the VOLUME control during a quiet
passage of the program until noise is clearly audi-
ble.
c. Turn the COMPANDOR selector knob to EX-
PAND. The Listen indicator will light over the
COMPANDOR pushbutton.
d. Rotate the RATIO control clockwise until the
noise is acceptably reduced.
e. Adjust the LEVEL MATCH control as described
previously.
2. To improve the "live" sound of recorded or
transmitted program material:
a. Select the LISTEN input.
b. Increase the VOLUME to a satisfactory level.
c. Turn the COMPANDOR selector to EXPAND.
d. Rotate the RATIO control clockwise until the
dynamic range of the music, the ratio of loud to
soft, is correct for you. The usual position will be
between 1.2 and 1.5
e. Adjust the LEVEL MATCH control as described
previously.
USING THE COMPANDOR AS A COMPRESSOR
When the COMPANDOR selector is in the COM-
PRESS position, the RATIO control is used to select
the amount of compression. Full counterclockwise
rotation corresponds to a ratio of 1.0. The compress-
or output and input dynamic range will be the same.
Set the VOLUME control to a normal listening level.
As the RATIO control is increased clockwise the out-
put dynamic range becomes less than the input
range. Set the RATIO control to the desired com-
pression. Switch the compressor on and off. A
change in the average listening level will usually be
heard. Adjust the LEVEL MATCH control until the
average listening level matches as closely as possi-
ble when the compressor is switched on and off.
After this adjustment you will notice that with the
compressor on, loud passages will be softer and
soft passages including noise will be louder.
When the RATIO control is at the fully clockwise
position it corresponds to a ratio of 2.0. The output
dynamic range is then one half of the input range.
This setting can be useful to create highly com-
pressed background music.
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