Joemeek twinQCS User Manual page 9

A COMPRESSOR is a device which reduces the dynamic range of
programme material.
WHAT IS A COMPRESSOR?
A perfect compressor is an amplifier where the input/output ratio is
constant: So using a 2:1 compressor, increasing the input by 2dB gives a
corresponding 1dB increase in the output. Early compressors which used
variable mu thermionic tubes or photoelectric devices only approximated
true compression over a limited range. They had a soft 'threshold' where
compression started and held to a predictable ratio up to a certain level,
then they returned to a more linear amplification allowing transients
through. This is in stark contrast to modern VCA compressor/limiters where
designers latched onto the idea that a compressor should be entirely linear
in its compression characteristic (regardless of the sound produced) and
thought it 'sensible' to combine the functions of compressor and limiter to
'stonewall' any and all signals above a certain level.
The musical effect is that VCA compressors sound muddy and flat, while
the historic compressors sound lively and retain sparkle.
But all compressors change the sound to some extent. The JOEMEEK
Studio Channel compressor adds 'punch' and 'bite' without the dull
muddiness of all others.
USING THE COMPRESSOR
A compressor IN/OUT switch is fitted. When this switch is pressed the blue
LED indicator above the switch is activated.
To USE the compressor, set the COMPRESSION control to about halfway.
·
Set SLOPE to number 3.
·
Set ATTACK to halfway,
·
Set RELEASE to halfway the release control at this setting will make
the compressor act to moderately control the gain, at higher
settings, sudden loud noises will cause the signal to remain
compressed for longer thereby restricting the gain more.
·
Switch the VU meter to 'COMP. METER' (switch out). - Don't forget
to turn up the output volume control too. If there is sufficient audio
signal from the input amplifiers, the meter will start to indicate
compression by the needle moving downwards.
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