On Oct 24, 5:44 am, Eeyore
wrote:
Patrick Turner wrote:
Eeyore wrote:
The definition of Class A is very simple. It requires that the output device(s)
never cease conducting under any signal condition.
It means slightly more than this because tubes don't cut off as sharply
as other devices.
I see what you're saying but I do believe that the definition is unchanged. Obviously
avoiding any region of significant non-linearity is preferable but that in its own right
doesn't change the definition.
Graham
Let's look at your definition again:
Poopie Stevenson wrote:
The definition of Class A is very simple. It requires that the output device(s)
never cease conducting under any signal condition.
Why don't you explain to us how a Class A amp can operate within the
class "under any signal condition", which presumably includes *much*
larger signals than the negative bias?
Your definition ipso facto makes Class A an impossible operating
condition because an increasing level of signal, permitted "under any
signal condition", will sooner or later drive the amp into cutoff. Of
course, long before then it will cease to be a high fidelity
amplifier, though, on the evidence of your posts, we don't expect that
to matter to you.
I repeat, a Class A amp, including that part of a Class AB amp
operating in Class A, are always and under any circumstances subject
to the designer's input signal limit or, if instead stated,
dissipation limit. To demand that a Class A amplifier work "under any
signal condition" is stupid for even a newbie, never mind someone like
you, Graham Stevenson, who claims to design electronic gear for sound
professional to use.
Andre Jute
Visit Jute on Amps at
http://members.lycos.co.uk/fiultra/
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