API Audio 527 Compressor - Manual (Page 3)

The patented
THRUST® function can be switched in and out
via the front panel as well, applying a high pass filter before
the RMS detector circuit that preserves that punchy bottom
end.
The 527 Compressor sections of two or more can be linked
together via a DC link allowing multiple units to be combined
for stereo and multichannel applications.
The output level remains fairly constant regardless of the
threshold or ratio control, much like the "more/less" Ceiling
control on the API 525 Compressor. This allows for live
adjustments without any noticeable gain changes in the
program level.
The 527 Compressor makes use of the 2510 and 2520 discrete
op-amps and exhibits the reliability, long life, and signature
sound which are characteristic of API products.
The API 527 Compressor takes its place alongside the family of
API VCA based compressors, the 225L and the 2500 Stereo
Bus Compressor. Anyone familiar with those units will
immediately be at home with the 527.
Features common to the line like "feed forward" (NEW) and
"feed back" (OLD) gain reduction methods selectable on the
front panel, provide a choice of "that old way", or "the new
way" of compression, for the highest level of flexibility in signal
gain control. The "old way" or Feed-Back method is what most
of the classic compressors used for the gain control circuit. The
"new way" gain reduction is more typical of the newer VCA
type compressors that rely on RMS detectors for the gain
control voltage.
There is a "SOFT"/"HARD" KNEE switch for an "over-easy" type
compression resulting in a very natural, uncompressed sound
or a typical sharp knee type that lends itself to a much more
severe limiting effect.
API 527 Compressor
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