Ashly LIMITER/COMPRESSORS CL-100 - Manual (Page 4)

ohms, and fiill headroom is realized with any load of600 ohms or greater. For
rack-mounted unbalanced audio ^^ms the output ground may be
separated from the case ground by using a stereo phone plug for the output
connection. The output ground is then wired to the ring of the stereo plugs
rather than the sleeve. In this manner, ground loops in the rack may be
eliminated. Ihis output can be fed to a balanced input by wiring the (+) input
to the tip, the (-) input to the ring, and the shield to ground
Stereo Tie
This patch point is used to tie tc^ether two or more CL-SOE’s (or
CLrlOO’s) for stereo or multi-channel operation. To connect, place a patch
cord between the STEREO TIE connections of both units. If signal ground
isolation is being used, be sure to use a stereo patch cord
NOTE: If more than two units are to be tied together, use a common “Y”
type adaptor to split the signal as necessary. The Stereo He point actually
represents the DC output of the detector circuit When tied in parallel for
stereo operation, the VGA’s of the two units will both respond to the most
negative control voltage present at the Stereo Tie point, thus insuring that
the stereo image never shifts left or right. The Stereo He points of CL-50E’s
and CL-lOO’s may be directly interconnected.
Detector Patch
The CL-50E and CL-100 Compressor/Iimitere have a DETECTOR
PATCH point whidi can be used in conjunction with an equalizer to produce
frequency-sensitive limiting. This and other uses of the Detector Patch are
discussed later.
Alternatives For Compressor/Limiter Sound System installations
To install the CL unit in a sound system using a passive crossover,
insert it between your mixing console output and the power amplifier input.
For systems using electronic crossovers, there are two ways to use an Ashly
compressor/limiter. If it is inserted between the console output and the
crossover input, it will act on the entire audio frequency spectrum.
Alternately, the compressor/limiter may be inserted between an output of the
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electronic crossover and the input of a power amp, in which case it will only
affect a specific band of firequencies. □
COMTROLS AND INDICATORS
Gain
The gain control is used to match the level of the signal source to the
fixed 0 dBV threshold of your Compressor/limiter. It should be adjusted so
the yellow threshold indicator iUuminates only when the signal reaches the
maximum level desired Then, above this level, the O)mpressor/Iimiter will
tend to minimize further increases in level.
Ratio
This control determines the ratio of change in output level to changes in
input level for all signals above threshold The numbers printed around the
Ratio control are calibrated in dB and indicate the dB increase in input above
threshold required to produce a 1 dB increase in output. This can be
expressed conveniently as a ratio. If the output remains constant no matter
how high the input level, we have an infinite (<») input/output ratio. It should
be remembered that the Ratio control has no effect on signals which are
below threshold, since the CLrSERIES products do not alter signals at below-
threshold levels.
There is a common but incorrect notion that limiting always implies the
use of an infinite ratio. Although there are times when an infinite ratio is
desirable, there will be situations where infinite, or “hard”, limiting action is
neither appropriate nor necessary. In fact, it should be noted that an infinite
ratio setting is likely to cause noticeable side effects in the sound, and may
not be usable on programs where subtle control is desired
Attack Time
The response of the compressor/limiter to signal levels above threshold
is fiuther defined by the ATTACK TIME control. Attack time is the amount
of time that the unit takes to attenuate the output level after threshold has
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