Automated Processes, Inc. 529 Operator's Manual - Page 10

Browse online or download pdf Operator's Manual for Air Compressor Automated Processes, Inc. 529. Automated Processes, Inc. 529 14 pages. Stereo compressor

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THRUST

The 529 Compressor includes API's patented THRUST

needed. This places the THRUST

reaction to low frequency content. The result is a noticeable increase of punch and low frequencies,

but a uniformly compressed signal. It's the "little more punch" switch!

The patented THRUST

Compressor, ATI Paragon and Paragon II consoles, as well as the Pro6 Input Strip. This circuit places a

filter in front of the RMS detector with a slope of 10dB per decade (-3dB/8va), which is the inverse of

the pink noise energy curve. In acoustics, the pink noise curve is used to equalize energy vs.

frequency over the audio spectrum, as sound requires more low frequency energy than high frequency

energy to sound correct to your ear. In Hi-fi equipment, a "LOUDNESS" contour is used to equalize the

music at lower levels so it sounds correct. Even with this curve, there is still a substantial amount of

low frequency information compared to high frequency information in the audio signal path. When that

signal is fed into the RMS detector, the detector will process the signal into a DC control voltage based

upon those louder low frequencies, resulting in a control voltage that favors the low frequencies of the

signal, causing pumping and a loss of punch. Sometimes, this is not desirable. By engaging the

THRUST

switch, this inverse filter is placed in front of the RMS detector, evening out the energy by

lowering the energy in the low frequencies and increasing the energy in the high frequencies, so each

octave has the same energy instead of each octave having half the energy as the one lower. This

creates a unique compression effect that still reduces the overall gain, but the sound is much more

punchy and the signal actually sounds less compressed.

THRUST

NORMal

NORMal: Flat: There is no filter in the path to the RMS detector and the 529 compresses like most

units on the market today.

5 2 9 S t e r e o C o m p r e s s o r

filter before the RMS detector that decreases the compressor's

circuit has been used for many years in the famed API 2500 Stereo

circuit that can be switched in or out as

A P I