Quote:
Originally Posted by primalsteve  I'm no technician but a technician once explained to me that one of the first signs of whether something is Class-A is whether there is a bipolar supply. If you see a PSU supply that has an audio voltage that has separate + and a - voltages there is a good chance it is not Class A. Something about "push and pull".
Steve Mabee |
Well, I agree with the part about not being a technician, and probably the guy who told you that as well.
From the Wikipedia:
"Amplifier classes
Amplifier circuits are classified as A, B, AB and C for analog designs, and class D and E for switching designs. For the analog classes, each class defines what proportion of the input signal cycle (called the angle of flow) is used to actually switch on the amplifying device:
Class A
100% of the input signal is used (conduction angle a = 360° or 2π)
Class AB
more than 50% but less than 100% is used. (181° to 359°, π < a < 2π)"
Has nothing to do with power supplies, a class "A" amp can be designed with bi-polar rails or just one power rail, same is true for class "AB".
The class "A" amp, being "on" all the time tends to run hotter.
OBTW, the Fleximix was an IC console, class "AB", and sounded (IMAO) great.