ISP Technologies SM 652 W/B - Manual (Page 4)

OPERATION
The HDDS Master Control Module is the Master control center for distributed sound
systems using the HDDS technology. The Master Control Module includes six zones
that can be used independently or can be linked to work together allowing the system
designer the flexibility to set up any system with the desired configuration. The block
diagram below shows the basic configuration of the SM652 Surface Mount Speaker.
The speaker receives power and audio over a Cat5 cable connected to the Master
Control Module, internally converts the AC power to plus / minus 15VDC and 30VDC to
power the amplifier. The audio signal is fed to a precision differential amplifier to
remove any common mode noise, equalized and fed to a D-CAT power amplifier circuit
and crossover to drive both the woofer and tweeter in the cabinet. The SM652 also
includes a built in liming circuit which limits the maximum audio output. The limiter is
set as a protection circuit that will allow the SM652 to reach its maximum output
without excessive clipping to protect the internal components from failure. The SM652
also includes thermal tracking and will mute the output if the internal amplifier
temperature exceeds 120 degrees centigrade.
The HDDS SM652 is available is both black and white. Both models include a front
mounted blue power indicator LED, which illuminates when power is on.