Aphex Punch Factory 1404 Instruction Manual page 8

Model 1404 Punch Factory
Expression
You will discover more great sounds on your instru-
ment, and certain musical genres will become more
playable. An example is blues. The Punch Factory
will blend the notes musically, making every note
audible without sucking out any of the feeling. Rich
sustains will not fade into oblivion.
Optical Compression - What Is It?
There are many, many ways to build a compres-
sor. Various devices can be used to create the core
circuit that controls the gain of the compressor in
response to a control signal. Each type of device
has its own advantages and disadvantages. Every
available technology has produced popular com-
pressors over the years. However, one of the most
beloved types of compressors is the "optical com-
pressor".
An optical compressor is created from the combina-
tion of a light sensitive resistor called a photocell,
and a controllable light source such as a small light
bulb or LED. Devices called optocouplers combine a
photocell and light source inside a light-proof pack-
age. The photocell changes its resistivity depending
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upon the intensity of the light.
Attack, Release & Memory
Compressors are said to be in "attack" when they
are in the act of reducing the gain and in "release"
when the gain is recovering, or rising back up
after an attack. Photocells exhibit a function called
"memory". When just a few brief attacks have
been experienced, the photocell recovers quite
fast, bringing back the level more quickly. However,
after repeated and constant attacking, the photocell
builds up a memory of the light pulses and recovers
more gradually. This helps to smooth out the com-
pression and preserve the quality of the sound.
The optocoupler used in the Punch Factory is
designed especially for audio and is produced
exclusively for Aphex. It has special characteristics
unusually well suited to music instrument compres-
sion. This means the Punch Factory is unique. No
other compressor sounds like this one.
Instruction Manual
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