Voice alarm amplifier

摘要

An emergency message output amplifier includes a plurality of audio output channels. Channels can be combined together to increase output power, and can be isolated from respective output speakers in response to detected faults and then disabled. The functional amplifier can be activated by itself and output current can be monitored to lower the output level enough to enable the amplifier to properly drive the existing load.

主权项

1. An amplifier comprising:
a plurality of independent audio output channels, each channel in the plurality includes a local, isolated, power supply and a channel power amplifier; switching elements which, in response to separate control signals, couple together outputs from different channel power amplifiers; and automatic gain control circuitry implemented independently on a per-channel basis.