back in my car audio days, i used phoenix gold amps, and Dynaudio mid's and highs, with Boston Acustic pro subs.. i was in the SQ crowd... and the phoenix gold amps had very true ratings.. but you paid for that......
with amps today, there are so many technologies that companies are using, analog, digital, and a combination of both...
the best way for someone to understand how an amp works is to learn how a class A amp works, when you understand how a class A amp works then you have a firm basic knowledge...
http://sound.westhost.com/class-a.htmin the home theater area, one of the biggest things to look at is the rating of the power supply, and the filter capacitors..
one example i am using is one of the amps that i have.
a Krell kav 250a
50,000 microfarads= uF of filter capacitance, a power transformer of 2kVA= (kilovolt amperes) rating
now for a yamaha RX-Z7 7.1 channel receiver.
(large E-core and 2 x 18,000uF= microfarads 71V capacitors)
i could not find the rating for the transformer..... but the krell amp is a 2 channel amp, where the yamaha has a 7 channel amp... and from the pictures the transformer in the yamaha can not even compare to the krell..
one reason the capacitors are important, the capacitors oppose a change in voltage, while a transformer opposes a change in current, as well as being able to change the voltage either up or down. depending on how you wire the capacitors and transformer in a perfect world neither the voltage or current will change... you have to keep in mind this is the power supply section of the amp... the is before your music is introduced into the circuitry...
this is a Krell amp, you can see the the majority of the amp is the power transformer, and at the top of the picture you can just barley see the blue capacitors. This is an older amp, but the electrical principles are the same no matter how old the electronics are.
this is one of the reasons that the pre-pro route is ideal solution, if money is not a huge deal.
