Andre Jute wrote:
I must say, Wilson, I don't understand why you're getting your knickers
in a knot. You're like those bolshies I used to know who claimed that
anyone who wasn't willing to kill for "socialism" was only play-acting.
Are you really claiming that someone who merely uses the NFB he finds
lurking in DHTs can't belong to the club until he repents and uses
excessive amounts of loop NFB? Are you really claiming that the use of
lots and lots of NFB is a prerequisite for good audio design? Are you
really claiming that because a little NFB is a good thing, an unlimited
amount must therefore be better, and an infinite amount best of all?
Seems a bit immoderate to me, old chap.
You will find yourself arguing at a man who has a head full of solid concrete.
Trev will never see the whole picture, and has never designed or built any amp in
the last 30 years.
I try not to bother arguing the same old tired BS time after time.
He just likes hanging out in news groups and Bull****ting.
He has NEVER once contributed a single article of constructive advice on tubecraft
at r.a.t.
Your hysterical belief that I am "against" NFB is the product of your
unsophisticated literal-mindedness. There is no reason for NFB to be an
act of faith, like an on-off switch. For the record, quite contrary to
your silly claims about what I said, I believe the little NFB that
occurs naturally in triodes and in certain conservatively sanctioned
traditional topologies are A Good Thing. To avoid giving you another
apoplectic fit, I shan't repeat what I think of the excessive amounts
of NFB required to make transistors work at all.
If you think you can write a more compelling argument than I can about
the evils of excessive NFB, have at it. But every time I see you, like
the other techies you merely kibbitz what better men have written.
I am now doing 845 amps, two per channel for 50 watts each.
I expect music to be real fine. Damping factor good, noise low,
bandwidth wide, distortions negligible and maybe I can add 6db of global NFB but
I doubt any difference due to some **added** NFB will be heard.
Trev has never done anything like this and simply doesn't understand.
With 845, just no need for the 106dB of added NFB used in SS amps.
I don't care a bit about what Trev says.
Patrick Turner.
Andre Jute
Trevor Wilson wrote:
"Andre Jute" wrote in message
ups.com...
Trevor Wilson wrote:
(a long commentary on my original post, all of it reproduced in full
below)
I never said an amp can work without NFB;
**Yes, you did. Several times, in fact.
that's your desperate spin on
the matter. In fact, I took part in a long thread which determined that
a 300B has about 12-14dB of internal or natural NFB.
**Then why do you persist in claiming that such an amp can exist with no
NFB?
You, Trevor
Wilson, know that what I actually believe is that most amps work better
without *added* negative feedback.
**I KNOW that you just published a bunch of lies and half truths. THAT is
what I DO know. If you want to publish a correction (which includes the
superior linearity of modern BJTs over triodes) then I will support you in
that endeavour.
And I told you so again:
It follows from the argument above that ultrafidelista should choose an
intrinsically linear topology and device which does not require added
negative feedback to 'linearize' the output.
See the "added"? It makes clear to even the rawest newbie what I
intend.
**No, it does not. I deal daily with newbies (and a goodly number of those
who aren't newbies) about the issues surrounding NFB. Most have no idea that
ALL amplifiers use NFB of some type for linearisation. Many more have no
idea that a triode utilises and internal NFB system. You have merely
perpetuated these myths. If you want to explain stuff, then be precise. If
you mean local NFB, say so. If you mean Global NFB, say so. If you mean
nested NFB, say so. Each feedback system will affect any given amplifier in
different ways. As you well (or bloody well should) know.
No one who has been in high level tube amps for more than a
semester needs it spelled out.
**Bull****! I see it every day.
Everyone knows the convention is that an
amp without added NFB is described as having Zero Negative Feedback.
**Piling more bull**** on top, does not make it so. Spell out EXACTLY what
you mean when you speak of feedback and there'll be fewer problems. If you
mean Zero GLOBAL NFB, then say so. As you well know, not all SS amps utilise
Global NFB for linearisation. In fact, they use similar feedback methods to
your triode amps. And, surprise surprise, they often provide many of the
benefits often ascribed to triode amps, without the obvious shortcomings.
But you would not want to actually educate people, would you?
You, Trevor Wilson, cannot fail to know it, therefore you are picking
desperate nits
**Nope. I just get tired of people like you perpetuating lies and half
truths.
-- and giving away your desperation by hysterically
screeching your misleading lie "no such thing as a ZNFB amp" over and
over again, probably more than twenty times (those who care can count
below).
**If you can manage some honesty and accuracy, then I would not nbeed to
correct your mistakes (lies?).
Your problem is that you know I'm right but that you have thirty years
invested in commercially telling people tubes are obsolete.
**You have no idea.
--
Trevor Wilson
www.rageaudio.com.au