Gotta say I'm not totally familiar with the McIntosh Power Guard trade mark but my chicken shite guess is its some form or another of a input/output comparator circuit.
Back in the early '70's Crown's DC-300A and DC-150A amplifiers called such a circuit IOC ... Input Output Comparator. Because of inherent and often destructive, threshold rail voltages in higher powered A/B amp designs .... don't most quality amps have such a IOC or "power Guard" implemented? Marketed as such or not?


Quote:
Originally Posted by legend94 View Post
pioneer lacks power guard which to me is the main reason to won mcintosh other than build quality.