Phoenix Gold Phorum

What is the difference between the various amp classes, a/b, d, etc? and what are pg amps?

alot of the old skool pg amps were ab, it is only more recently that the rsd monoblocks are ds; however bfowler may be able to tell you(me), us, if the xenons were class d or not????( usually in the manuel amp section the specs will tell you-ie- a ti 1200.1 is a class a/b= uses alot of juice, or current, where as , per my understanding, the class ds use less currrent, while still delivering lots of power, and better efficency, i think thats how i understand it, but im not an amp expert, cuz if i was, id be building them similar to old skool pg, i believe the market is still there, espically after being is this phorum since early this year, and the rate the old pg amps sale for here, and on ebay-

^nice link

to summerize

all the PG full range amps are class AB. the large mono channels since the octnae R line have been "D" (exceptions are the tantrum 1200.1 which was a "chip" amp and the RSD 300.1 is a mono channel A/B with a non-defeatable lowpass crossover)

i don't know on a circuitry level what the difference is, but a/b amps are cleaner sounding, but are very inefficient. while class D amps are very efficient, but emmit a high pitch noise into the signal. this is why they are only used for lowpass. (until recently with the aid of digital chips like the alpine pdx and JL HD amps) the subs are crossed over below that noise level anyway, so its deemed a mute point (although some say they can hear the noise and prefer A/B amps still)

THD is generally much higher on a class D amp is it not?

http://www.bcae1.com/ampclass.htm This has some good explanations on it.

Yessir...lots of that is the higher frequency noise, but some is not. i can't hear the noise in the few D classes i have used, but i'm sure many can