Audio Engineering

Interfacing and Processing 279

With a virtual control surface, the traditional limitation vanishes. In turn, installation
setup, constant awareness of status, and troubleshooting of amplifi ers in medium to large
installations are all enhanced. One person can “ be in six places at once. ”

The Dutch PA system manufacturer Stage Accompany was a pioneer of the computer-
controlled and monitored PA system in the mid-1980s. However, the fi rst widespread
commercial system that wasn’t a dedicated, integrated type was Crown’s IQ , running on
Apple Macintosh (1986). The second was Crest Audio’s aptly named Nexsys, running
on PC. Most subsequent systems have been IBM-PC-compatible types, running under
Microsoft’s Windows. Every system is different, yet offers similar, fairly predictable
features; there is no clear-cut choice. At the time of writing (1996), some “ future
proofed ” universal, nonpartisan, networkable system contenders that seem most likely
to become industry standards appear to have priced themselves out of consideration.
Instead, makers continue rolling their own. Recent examples include the IA (intelligent
Amplifi er) system by C-Audio , the MIDl-based interface used by MC 2 (UK), and QSC’s
Dataport system.

Input

HT

82 K

3K9

4K7

3K9

82 K controlMute

HT 1 M Mute JFET

680

680 2 K7

To

power

stage

Figure 8.12 : A typical soft clip circuit as used in the Otis Power Station amplifi er.

Copyright Mead & Co. 1988.