|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
71.187.201.31
In Reply to: RE: Audio Pet Peeve posted by slapshot on August 26, 2014 at 13:33:19
mine is trivial but it shows how little audiophiles know about the nature of reproduction - single ended class A. Single ended has to be class A by the very nature of its topology.
Follow Ups:
"mine is trivial but it shows how little audiophiles know about the nature of reproduction - single ended class A. Single ended has to be class A by the very nature of its topology."
True, but I've only seen the phrase used in the context of which type of Class A topology is utilized. (The other type being "push-pull Class A".)
> ...mine is trivial but it shows how little audiophiles know about the nature of reproduction...>
Yes, very trivial.
"nature of reproduction"???
Circuit topology and design, perhaps.
Audiophiles use that term because smart amp designers have been using it for years and years now. There must be a *reason* for that name - does anyone know what that reason might be? Read any number of articles by designers like Nelson Pass (or others) and you'll see the term "single-ended class A" being used pretty frequently.Also, notice that Nelson refers to a "push-pull class A" circuit in this article. A misprint, perhaps?
Edits: 08/26/14 08/26/14 08/26/14 08/27/14
You can have push pull class A. Who's calling who dumb
Alan
There's A1 with no grid current, and A2, where significant grid current is drawn. Also, combinations of the two (A1 up to certain power, then A2).
The simple definition of Class A is when the current never cuts off.
One could build an amplifier where all the tubes work in Class A and still end up with a distorted mess.
Most of the examples in the text books of Class A are "Linear Class A" (my words) where the tubes are biased in the middle of the most linear part of the dynamic curve and only allowed to operate within the most linear part of that curve.
That is my definition of Class A. I have caught a lot of flak for that.
In the end I guess it's Class A as long as the current never shuts off but who wants to waste time talking about bad Class A?
As an aside, some of the old books talk about the "cutoff region". This is the region approaching cutoff (but before reaching it) where the operation becomes very non-linear. And those books define Class A operation as not operated in the cutoff region, but only in the linear region.
So in the end you have to ask, "What kind of Class A?".
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
I think that when when engineers like Nelson Pass bother to say "single-ended class A" instead of simply saying "single-ended", they are not being dumb. They are simply trying to be very specific.
Well, "...how little audiophiles know..." is what hahax said, right?Hey, I know that knowing too much creates just as many problems as being dumb does. That's why I choose to stand proud...
My point is, audiophiles aren't necessarily using the term "single-ended class A" because they know "little". More likely, they are using it because those who know a lot use it.
Edits: 08/27/14
Post a Followup:
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: