Installation manual

Audio International, Inc. PA-475-A (-B) (-C) Installation
Document #540021, Rev. C, 4/2000 Page 5 of 12
2.0 Application
2.1 Introduction
The PA-475-A, PA-475-B, and PA-475-C are audio amplifiers that will
produce stereo audio output for the entertainment system and monaural
audio for page / chime. Up to four (4) midrange / tweeter and four (4)
subwoofers can be connected to an amplifier.
Each amplifier is designed to interface with AI’s proprietary RS485 serial
data bus allowing all entertainment switch panels to communicate with the
audio amplifier.
The differences between the units is as follows:
The PA-475-A has the capability of producing four (4) channels,
75 watts RMS peak output, 150 maximum per channel output
power. Output impedance 4-ohms per channel. Electric
crossover low range 20 – 135 Hz, high range 135 – 20 kHz.
The PA-475-B has the capability of producing four (4) channels,
50 watts RMS peak output, 100 maximum per channel output
power. Output impedance 4-ohms per channel. Electric
crossover low range 20 – 135 Hz, high range 135 – 20 kHz.
The PA-475-C has the capability of producing four (4) channels,
50 watts RMS peak output, 100 maximum per channel output
power. Output impedance 4-ohms per channel. Electric
crossover low range 20 – 300 Hz, high range 300 – 2 kHz
2.2 Block Diagram – Typical Application