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Q: Well, one of the things about Parasound amps, they are very rugged and that’s - is it an important part of your belief in amps?
JC: Well, it's not me that does that. Over the years Parasound has developed some very effective protection circuitry. It has an output relay that could be problematic in extreme circumstances. It’s kind of like a rev limiter on a car. It doesn't do anything until you exceed the redline, and then it cuts power to keep the engine from blowing. It could reduce your performance sometimes if you like to push your engine beyond the redline. It depends on what you want. Do you want to be a hot rodder or do you want your engine to hold together? I have an old Porsche and it just can’t breathe. It has a hard time just getting up to 6,000 rpm, which is it’s red line. You’re saying what am I doing here? I'd better shift because I’m not going anywhere. I also have an Acura and, man, that thing kicks in from 5,000 to 7000 rpm and I’m always going through the rev limiter at 7,000. If I didn’t have a rev limiter, it’d be gone. Parasound's amps use a very sophisticated protection circuit that they’ve or developed over the years, and basically it's the equivalent of a rev limiter. It senses a number of things and when you’re in trouble and it’s too hot it fires this circuit to open the relay and protect the amplifier and the speakers. It’s a lot better than fuses, because fuses are non - linear. They can’t help it. They are designed to have to heat up before they blow up. This heating process changes it’s resistance. The resistance invariably rises as the temperature goes up --that’s pretty much the laws of physics-- and of course it’s going to modulate. If you have a lot of current flow, even though you’re below the limit of the fuse, the darn fuse is going to modulate. Of course, this is almost impossible to measure statically. Once you put a resistive load on and a certain amount of power the fuse is going to up to it’s temperature and stay there and the resistance is not going to change very quickly, so you never know that the fuse is distorting. It only distorts getting up there and then going back down. It doesn’t necessarily distort by the time you’re ready to make the measurements. That’s one of our problems with static measurements. You just don’t know everything that you need to know.
