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DUAL/STEREO COMPRESSOR/NOISE GATE CN-220
unwanted noises. For this reason, the unit provides an EARTH-LINK switch placed at the rear panel
in order to lift the mains earth from the unit.
MAINS EARTH LINKED WITH THE COMPRESSOR/NOISE GATE
ELECTRIC GROUND.
MAINS EARTH LIFTED FROM THE COMPRESSOR/NOISE GATE
ELECTRIC GROUND.
NOTE:
For security reasons, the earth connection to the mains is linked with the unit chassis in both
cases.
CAUTION:
Always operate the unit with the AC ground wire connected to the
electrical system ground. Precautions should be taken so that the means of
grounding of a piece of equipment is not defeated. For this circumstance,
NEVER
lift the mains earth AC ground to avoid possible accidents. For your security, NEVER
use ground isolator adapters; instead it is recommended the EARTH -LINK switch.
5. OPERATION
The dynamic range of an audio equipment is limited by the maximum signal level that the
audio equipment can drain without audible distortion and the noise generated by this audio
equipment.
The noise, is generated by the audio equipment because of the current flowing the conductors,
due to the random electron movements. For statistical reasons, this produces frequencies within the
whole audio spectrum. This noise is called white noise. If this noise is then strongly amplified, a noise
will be obtained perfectly audible.
The maximum signal level of the audio equipment is limited by the levels of the internal
operating voltages. If the signal exceeded the internal operating voltages, audible signal distortion is
the result. In practice, this limitation is greater, since a certain reserve must be maintained to avoid
distortion of the audio signal if sudden level peak occur. In technical words, we refer to this reserve as
“headroom”. If we reduce the input signal level, we reduce the risk of signal distortion due to level
peeks, however, at the same time, the noise floor level will be increased if we want obtain the same
output signal level, since, we must amplify more.
The compressor/limiter act as automatic gain controls, decreasing the signal level above a
certain level (THRESHOLD), restricting the dynamic range and allowing us increase the audio
equipment headroom, without decrease the input signal level. The difference between a compressor
and a limiter, is that limiters abruptly limit the signal above the threshold while the compressors will
decrease the signal level above the threshold, depend on the compression ratio set up and the ratio
of the input signal level and the threshold, it’s to say, gradually.
How we explained previously, the noise limits the audio equipment dynamic range. The noise
gates decrease the signal gain abruptly bellow the threshold allowing increase the audio equipment
dynamic range, achieving the inverse function of a compressor/limiter.
The ALTAIR CN-220 incorporates a dual Compressor-Limiter with a full-featured Noise Gate
connected internally.
NOISE GATE
TEST MONITOR SWITCH (SIDE TEST)
