What is class A electronics ?

[andre tchmil]

Can someone explain what Class A discrete means.

low profile simple man explanation please :green:

 

[clintrubber]

Did you search ? Lots of info on 'class A' around. Maybe too much actually...

'Discrete' is an attribute that's actually separate from 'class A', it just indicates it's using separate devices, as opposed to integrated circuits.

Not to confuse you, but 'discrete' will usually also mean it's 'solid state', but an EF86 tube could be thought of as a discrete amplifier-element as well (in contrast to existing but rare integrated tubed circuits). But please ignore all this small print.

 

[jrmintz]

There's an interesting article about this on the Mesa Boogie web site

 

[cuelist]

http://sound.westhost.com/class-a.htm

http://www.st-andrews.ac.uk/~www_pa/Scots_Guide/audio/part2/page2.html



Or put simply....

Put simply - class A is a way of using transistors (or tubes) to drive the load without the devices ever switching off completely. It's not very effecient and thus creates a fair of amount of heat as the "idle" current of the devices is set fairly high.

Class B means that one device handles the positive part of the signal and another one the negative part. It's the "handing over" from one device to the other that is the issue. Any glitch will result in some called crossover distortion.

Class AB means that the amplifier runs in class A up to a certain point (current) and thereafter as class B.

Note - discrete is not the same as class A. Discrete is the opposite of integrated (as in intergrated circuit).

 

[Gus]

http://www.aikenamps.com/TechInfo.htm

Look for the Vox writeup

 

[CJ]

Class A means current flows all the time.
Just ingrain that in the main membrane and your set for life.

 

[andre tchmil]

Thank you all.

 

[peter purpose]

Class A discrete..... chop em out in the broom cupboard.. :green:

 

[CJ]

:razz: