Re: Stability in Feedback Amplifiers, Part Deux-A



Henry Pasternack wrote:

"Patrick Turner" <info@xxxxxxxxxxxxxxxxxx> wrote in message news:463FE676.4527801F@xxxxxxxxxxxxxxxxxxxxx
[Deleted]

Patrick, I agree you don't need much math beyond Ohm's law to build a good
tube amplifier. I also agree that it takes years of study to learn all that Bode,
Laplace, Fourier, and Nyquist stuff. What I disagree with is your calling the
theory boring, impractical, and of no real value. To me, when you make
comments like that it just sounds ignorant and insecure.

Nope, not ignorant, not insecure. If ever i need to cuddle up to
the ideas of the Four Guys, I know where they are, but meanwhile have
not got time
and am too busy.

For those who want to construct a discussion to relate what the FGs said
about
wave behaviours to amplifier stabilising techniques, fine, just get on
with it
and quit roasting ppl like me who just get on with the practice rather
than theory.

If you contend I am missing out somewhere, then post constructively
rather than
complain.

We all look forward to your dissertations on the FGs.


It was such hard work going to engineering school that I can't imagine doing
it over again at my age, let alone the typical amateur trying to pick it all up
on his own.

Don't expect me to be a theoretical expert, or expert on theory.

I an too busy making amplifiers.


Over the years I've forgotten many of the details of what I learned
in college.

That is because you don't use the theory everyday in your work.

I was the same when I was a construction doer. In my 20s went to night
colledge for 5 years
and had to learn about Theory of Structures, and be able to design any
building, dam, retaining wall,
bridge, and so on, but not because we'd use what we learnt, but because
as builders we needed
to be taught respect of engineers and architects. Some big-wig someplace
decreed that builders
must respect engineers and architects, and included lofty subjects into
the course.
And we did respect gingerbeers and artichokes as a result.
It came in very handy when i came later to design and consruct domestic
house improvements.
Work I designed only had to be verified by an engineer, so his fee was
nice and low.
I earned the architects fee.
All the work I designed and built was approved by authorities.

Domestic house renovations are like amplifiers, simple, and don't
need graduate engineers to design them.
But for large telecommications networks and broadcast studios, sure, the
engineer is essential.

I also learnt Quantity Surveying in my Building Certificate course.
We had to be able to work out the exact number of bricks correct to +/-
1/2 a brick in a
given design for a house or block of flats.
It was infuriatingly boring, but I got there, with only a slide rule.
But it taught me how to give a better itemised quote and win contracts
when i traded
in the house alteration market.

So sometimes i used what they taught me, and sometimes I didn't.
I have in the past worked for a couple of clients who built
their homes which were very well conceived designs and all without an
artichoke or gingerbeer.
They couldn't get the carpentry right, so they employed me, and I was a
whiz with
complex angles and anything requiring a figure out.

Did I need to know the complex structure of the cells in a tree
to be a good chippy? NO.



But I've retained most of the conceptual framework. I'm interested
in whether those concepts can be explained in simple enough terms, without
all the details, so that a non-specialist audience can benefit from them.

I would be too, so why doesn't someone just get on with it?

But the devil is in the detail, and the detail needs a drawing in the
case of Bode,
so no drawing, and just what is there to discuss? words about other
words about other words put people off to sleep.

I think if you're a gifted teacher and you really know what you're talking about,
it is possible to make this connection to the general audience. I don't post
here very much because, frankly, the newsgroup sucks.

Then you have let it suck by leaving it.

If you want the group to blow instead of suck, provide pressure, not
suction.

Ask not what your group may do for you, ask what you may do for your
group!!

But I do post some
pretty technical articles over on Audio Asylum and a lot of people seem to
appreciate them.

Yeah, and all those guys know where we are, and many wouldn't dare dip a
toe
into the waters here because the crocs will bite it off merrily if
they make no sense.


It's time consuming to be a resident guru. I don't have the time anymore the
way I used to. And there are too many wackos on the internet now. Who
needs the hassle?

I don't have time to be guru either.

Often these people don't make many amps.



I've looked at your website. There's a lot of information there, but where's
the added value? Compare and contrast with John Broskie's site. There
really is no comparison.

There is no accounting for taste.

I didn't see too many photos of what he's built for anyone.

Broskie is another interesting audio website.

My ISP said I had 118,000 hits last february alone.
Maybe I am useful to someone, somewhere. None who email me privately
for adice about their amplifier or transformer building projects want to
know about Fourier, Laplace, Bode or Nyquist.
They only have to toddle up to any university library to find out
all they might want to know.

The theoretical aspects behind audio wave motions is all well set out
in books and websites all over the place ( although not much as
Broskies's joint),
and why would I need to repeat it all at my site?

But should you yourself want to provide an article so I may include it
at my site in
a page devoted to FGs, then do so. I have a 200MB content limit, but use
only 18MB.



Please don't make me laugh by questioning my credentials.

I'll stop laughing if you stop talking down to me, and don't
stop whingeing about r.a.t content without doing anything to improve
matters
by adding content and treating others as an equal.

Its a fabulously rewarding deal.


You should post less and say more. Sadly, I don't think enough of the good
people are still around to restore the group to a semblance of health. But it's
not a great loss, because there are so many thriving forums to visit on the web
nowadays. In most respects, things are better than ever in the online audio
community, even if you wouldn't know it from reading rec.audio.tubes.

I don't find any of the little private groups very interesting.
They dare not come here to discuss anything, lest they get their heads
bitten off for BS.

I doubt they like to risk being really challenged. I don't mind.

I get enogh good review from people I make amplifiers for to
boost me along. I'm here to spread the message about how to achieve
success with tubes. Its mainly a bull*** free message, simple as it
can be,
without being plain wrong and its for the layman who wouldn't know a
Fourier equation even if it bit him on his arse.

The theorists are welcome, but I hope they don't bore us all to death,
or make idiots out of themselves by nit picking and arguing over ever
little thing.


Someone set out to try and establish was a how - to - do document
for getting amplifier stablity.

If you wish the result to be where you want it, make it so yourself,
don't ask me, I am too busy, OK.




Oh well. Have a nice day.

-Henry

Patrick Turner.
.

Loading