On 14 Jun 2004 18:09:01 GMT, ohawker (Andy
Evans) wrote:

Are you telling me that your designs are so incompetent that (blah blah).

I repeat exactly what I said before. Give me a selection of valve circuits that
you have personally designed, with detailed construction notes showing that
changing componants had no effect on he sound.

See below:
What I propose is that you give me a selection of your own valve amplifier
circuit designs with your detailed construction notes which prove that
substituting componants has no effect on the sound. In return I will give you a
selection of my own valve amplifier circuit designs with my detailed
construction notes on the diverse effects of substituting componants. You are
welcome to breadboard my circuits with the relevant parts to check whether your
own ears confirm the effects I have found. That sounds reasonable doesn't it?
Let's put this to the test.







=== Andy Evans ===
Visit our Website:- http://www.artsandmedia.com
Audio, music and health pages and interesting links.

My valve design - years ago now - was concerned with a discipline
vastly more demanding than audio; measurement. I designed equipment
for measuring labs, including the National Physical Laboratory. I can
assure you that although I selected components, the parameters were
all to do with reliability and stability; I never found any that would
alter performance by their substitution. That was because I designed
circuits properly, making sure that stability and performance did not
hang on some unpredictable parameter in a component. It isn;t the
easiest way to do it, but it is the right way. If you are seriously
suggesting that your amplifiers perform differently with carbon
resistors than with metal ones, despite the values being the same,
then you are doing something wrong.

Probably Jim has it right when he suggests the problem may be marginal
stability which is causing the amplifier to oscillate with the changed
parasitics of one component type. That would be a logical assumption
based on your evidence. But all that points to is incompetence of
design, not some mystical property of components (hint - they don't
have any!).

d
Pearce Consulting
http://www.pearce.uk.com

On Mon, 14 Jun 2004 20:21:09 GMT, "Trevor Wilson"
wrote:


"Don Pearce" wrote in message
.. .
On Mon, 14 Jun 2004 08:43:02 +0100, Jim Lesurf


This problem is particularly to be found in the "high end", where
there is simply not enough time and money to develop a design
properly, which generally takes a large number of models to establish
- as you imply - criteria for tolerance sensitivity, stability etc.
The result is that every unit sold is essentially an under-designed,
under-tested prototype, which really should never have left the
premises.

**Nonsense. High end designs can be very mature, depending on the talent of
the designer and his manufacturing team. SOME designs are as you say they
are, however.


A properly-engineered design simply never gets the chance to happen in
this market, whereas further down the food chain, not only can it
happen, but it absolutely MUST happen, or heads start rolling.

**Utter and complete ********. In a past life, I was service manager of
Marantz (Australia). Each month I received a flood of modification sheets
for many Marantz models. These ranged from relatively minor stuff, to major
mods to various products. One of those products concerned an amplifier which
I still own. The Marantz Model 500 power amp. An impressive beast, of (then)
prodigious power output. The 500 was stunningly unreliable, mostly due to
the use of complementary symmetry output devices, at a time when such
devices were both unreliable and of marginal ratings. 300 amps were
manufactured by Marantz USA. They had an RRP of AUS$1,500.00 in 1974. Three
units were imported into Australia and each amp (with the exception of mine)
had to be serviced around 5-6 times, before head office figured out how to
prevent them from self-destructing every few weeks. Each repair took around
10-12 hours. Rumour has it that the entire Model 500 project cost Superscope
inc (Marantz's owners) US$3 million, from cradle to grave (initial design,
to the end of the warranty period). It almost sent them to the wall.

Along with mod sheets, I also had access to a fascinating document, which
outlined the reliability figures of every Marantz model (for the duration of
the 3 year warranty period). The legendary Model 1070 enjoyed a failure rate
of 0.5%, whilst the 4230 enjoyed a failure rate of 60%. The Model 500
enjoyed a failure rate of 100%.

I am presently a service agent for a number of large, well known brands.
Whilst chatting to the service manager of one of these brands, he casually
mentioned that their then current DVD player enjoyed a 63% failure rate. And
this was in 2003, not 1973!

Make no mistake: MANY designs are being produced which are incomplete
designs. It will always be that way, it seems.

And that is just the designs that have gone through a complete and
thorough development cycle.

The big difference with the "High End" stuff is that you don't get the
recall, the modification notice. It just stays out there performing
like ****, with the brain damaged owners saying "Great - it really
sounds different to all that mid-fi stuff".

And of course back at base there is some engineer saying "oops!, when
I change this metal resistor to a carbon type, the sound changes -
what should I do?" At Marantz, the answer comes back "Find the problem
and issue a bulletin - get it done before end of work today, we can't
afford the ****". In other places they say "What do you mean fix it,
lets boast about it on Usenet". I name no names, of course.

d
Pearce Consulting
http://www.pearce.uk.com

But all that points to is incompetence of
design, not some mystical property of components (hint - they don't
have any!).

With your condescending attitude and plain lack of understanding of the
creative process, I'm surprised you get any work as a consultant. Maybe you
don't. Like you can't provide me with any of your own design valve circuits
despite pretending to be an authority and putting down everyone else. Sad.

=== Andy Evans ===
Visit our Website:- http://www.artsandmedia.com
Audio, music and health pages and interesting links.

"Jim Lesurf" wrote in message
...
In article ,
Keith G wrote:

"Jim Lesurf" wrote in message
...


I quite like films like "When Worlds Collide" and they cut to "the
computer" and show lots of whirling rods and cams. :-)


...... being operated by a mechanical Olivetti adding machine with the
handle ripped off, like in The Prisoner rerun, a day or two ago!

:-)

Well, I do still have a Brunsvega mechanical adding machine. At one time I
used to know how to do square roots on it, but I forgot this years ago!

Still have a slipstick as well.. ;-

**Me too. I have the finest one ever made. The mighty Faber Castel 2/83N. I
bought for a song, from a guy who purchased a calculator. I've been trying
to teach my partner how to use it. She grew up in a time without slide
rules. Seven years after me, they were all gone.


--
Trevor Wilson
www.rageaudio.com.au

On 14 Jun 2004 22:50:11 GMT, ohawker (Andy
Evans) wrote:

But all that points to is incompetence of
design, not some mystical property of components (hint - they don't
have any!).

With your condescending attitude and plain lack of understanding of the
creative process, I'm surprised you get any work as a consultant. Maybe you
don't. Like you can't provide me with any of your own design valve circuits
despite pretending to be an authority and putting down everyone else. Sad.

=== Andy Evans ===
Visit our Website:- http://www.artsandmedia.com
Audio, music and health pages and interesting links.

No, it isn't condescending to point out that the emperor is not
wearing any clothes. If you and your kind want to carry on your nasty
little con act whereby you persuade the lame of brain that you possess
some kind of arcane knowledge and ability that they can't share,
unless they buy the magic beans from you, then yes - I will stand up
and yell.

For further laughs may I direct the casual reader to Andy's web site
where he can find such gems as speaker cables that cause hum if they
aren't braided right. Apparently it is RF interference that causes
this. Apparently women can tell you how to do this (no condescension
there then!) Be further tickled by the fact that they start out
bright, but get mellow as they burn in.

There is a nice comparison of tubes too. Would anyone like to hear a
round, wooden grand piano? Yes? You will find it here folks!
Apparently it is caused by having a double mica spacing washer and
plates that are brown or grey. Right. Never knew that.

It is very evident from the above that your expertise lies in the
creative media, and your understanding of the engineering needed for
amplifier design amounts to zero. Perhaps you could take one of your
own counseling sessions to help you come to terms with your fame.

d
Pearce Consulting
http://www.pearce.uk.com

"Don Pearce" wrote in message
...
On Mon, 14 Jun 2004 20:21:09 GMT, "Trevor Wilson"
wrote:


"Don Pearce" wrote in message
.. .
On Mon, 14 Jun 2004 08:43:02 +0100, Jim Lesurf


This problem is particularly to be found in the "high end", where
there is simply not enough time and money to develop a design
properly, which generally takes a large number of models to establish
- as you imply - criteria for tolerance sensitivity, stability etc.
The result is that every unit sold is essentially an under-designed,
under-tested prototype, which really should never have left the
premises.

**Nonsense. High end designs can be very mature, depending on the talent
of
the designer and his manufacturing team. SOME designs are as you say they
are, however.


A properly-engineered design simply never gets the chance to happen in
this market, whereas further down the food chain, not only can it
happen, but it absolutely MUST happen, or heads start rolling.

**Utter and complete ********. In a past life, I was service manager of
Marantz (Australia). Each month I received a flood of modification sheets
for many Marantz models. These ranged from relatively minor stuff, to
major
mods to various products. One of those products concerned an amplifier
which
I still own. The Marantz Model 500 power amp. An impressive beast, of
(then)
prodigious power output. The 500 was stunningly unreliable, mostly due to
the use of complementary symmetry output devices, at a time when such
devices were both unreliable and of marginal ratings. 300 amps were
manufactured by Marantz USA. They had an RRP of AUS$1,500.00 in 1974.
Three
units were imported into Australia and each amp (with the exception of
mine)
had to be serviced around 5-6 times, before head office figured out how
to
prevent them from self-destructing every few weeks. Each repair took
around
10-12 hours. Rumour has it that the entire Model 500 project cost
Superscope
inc (Marantz's owners) US$3 million, from cradle to grave (initial
design,
to the end of the warranty period). It almost sent them to the wall.

Along with mod sheets, I also had access to a fascinating document, which
outlined the reliability figures of every Marantz model (for the duration
of
the 3 year warranty period). The legendary Model 1070 enjoyed a failure
rate
of 0.5%, whilst the 4230 enjoyed a failure rate of 60%. The Model 500
enjoyed a failure rate of 100%.

I am presently a service agent for a number of large, well known brands.
Whilst chatting to the service manager of one of these brands, he
casually
mentioned that their then current DVD player enjoyed a 63% failure rate.
And
this was in 2003, not 1973!

Make no mistake: MANY designs are being produced which are incomplete
designs. It will always be that way, it seems.

And that is just the designs that have gone through a complete and
thorough development cycle.

The big difference with the "High End" stuff is that you don't get the
recall, the modification notice.

**It would be disingenuous to suggest such a thing. I know of several high
end manufacturers who not only have a very personal relationship with their
clients (try that with Pioneer), but will service their product and
incorporate updates well after any warranty period has ceased. The mass
market guys, OTOH, just tell you to buy the latest model. I know this from
personal experience. Just today, I received a new player from a
manufacturer, who no longer supplies spares for a particular product in
their line-up. The product is still within its warranty period! After the
warranty ends, tough luck. Many high end manufacturers tend to provide
support for many, many years. Well past their statuatory requirements. Here
in Australia, that requirement is 7 years. One manufacturer, I service
equipment for, still supports products manufactured back in 1976.

It just stays out there performing
like ****, with the brain damaged owners saying "Great - it really
sounds different to all that mid-fi stuff".

**Sometimes there is a good reason to say so. Some of that mid fi stuff is
pretty bad. Some of the high end stuff is pretty good. Mind you: SOME of the
mid fi stuff (Rotel, et al) is excellent and some of the high end stuff is
pretty horrible.


And of course back at base there is some engineer saying "oops!, when
I change this metal resistor to a carbon type, the sound changes -
what should I do?" At Marantz, the answer comes back "Find the problem
and issue a bulletin - get it done before end of work today, we can't
afford the ****". In other places they say "What do you mean fix it,
lets boast about it on Usenet". I name no names, of course.

**The problem with my example of Marantz, is that the bulletin came TWO FULL
YEARS into the retail cycle. By that time, owners had suffered immensely.


--
Trevor Wilson
www.rageaudio.com.au

It is very evident from the above that your expertise lies in the creative
media

Yes it is - that's why I enjoy building amps. I am completely self taught
electronically over about 20 years, but I can say that I've built dozens of
amps and speakers which all performed well. You, on the other hand, whatever
you know about engineering, have the social skills of a dead rat (possibly).
May I suggest some basic psychology, or failing that simply dump the sarcasm. I
can assure you that nobody laughs at smug self-satisfied condescending oiks
except themselves. This is from long experience on the net of lifting up stones
and finding arrogant little ****s like yourself crawling about underneath.
Newsgroups are places for enthusiasts to exchange ideas, not condescending
know-it-alls to call everybody stupid.Think about it.


=== Andy Evans ===
Visit our Website:- http://www.artsandmedia.com
Audio, music and health pages and interesting links.

On 15 Jun 2004 06:03:08 GMT, ohawker (Andy
Evans) wrote:

It is very evident from the above that your expertise lies in the creative
media

Yes it is - that's why I enjoy building amps. I am completely self taught
electronically over about 20 years, but I can say that I've built dozens of
amps and speakers which all performed well. You, on the other hand, whatever
you know about engineering, have the social skills of a dead rat (possibly).
May I suggest some basic psychology, or failing that simply dump the sarcasm. I
can assure you that nobody laughs at smug self-satisfied condescending oiks
except themselves. This is from long experience on the net of lifting up stones
and finding arrogant little ****s like yourself crawling about underneath.
Newsgroups are places for enthusiasts to exchange ideas, not condescending
know-it-alls to call everybody stupid.Think about it.


=== Andy Evans ===
Visit our Website:- http://www.artsandmedia.com
Audio, music and health pages and interesting links.

Thank you - I will gladly take an example from this post of yours. It
is a shining example of the way your ability with words matches your
ability with electronics - both produce pretty much the same result.
Your engineering rigour is a good match for the social skills you
demonstrate here.

But do keep flogging the snake oil; we need charlatans like you to
keep the rest of us looking good.

d
Pearce Consulting
http://www.pearce.uk.com

On 15 Jun 2004 06:03:08 GMT, ohawker (Andy
Evans) wrote:

It is very evident from the above that your expertise lies in the creative
media

Yes it is - that's why I enjoy building amps. I am completely self taught
electronically over about 20 years, but I can say that I've built dozens of
amps and speakers which all performed well. You, on the other hand, whatever
you know about engineering, have the social skills of a dead rat (possibly).
May I suggest some basic psychology, or failing that simply dump the sarcasm. I
can assure you that nobody laughs at smug self-satisfied condescending oiks
except themselves. This is from long experience on the net of lifting up stones
and finding arrogant little ****s like yourself crawling about underneath.
Newsgroups are places for enthusiasts to exchange ideas, not condescending
know-it-alls to call everybody stupid.Think about it.


=== Andy Evans ===
Visit our Website:- http://www.artsandmedia.com
Audio, music and health pages and interesting links.

Incidentally Andy, I'm not calling everybody stupid. I'm calling YOU
stupid. Think about it.

d
Pearce Consulting
http://www.pearce.uk.com

But do keep flogging the snake oil; we need charlatans like you to keep the
rest of us looking good.

I've asked you for a selection of your valve amp circuits and you don't have
any. I've told you I've built several good sounding valve amps and I can
provide you with circuits and detailed consruction notes and you ignore me. All
that seems to come from you is hot air, which doesn't even seem to contain any
useful electron streams. I am angry with you because you put people down. I am
angry with you because you are smug and arrogant. I am angry with you because
you turn newsgroups which are for the enjoyment of enthusiasts - right or wrong
in their explorations - into some self propelled crusade to 'expose
incompetence'. I am angry with you because you are inflexible. I am angry with
you because on a nice summer day you seem incapable of goodwill towards others.
I am angry with you because if you have any sense of humour you sure don't use
it. I am angry with you because you make me angry. Probably others are angry
with you too. You don't 'expose incompetence' - you simply get on people's
nerves. What makes you think you have a right to dictate to others? What makes
you think people want to know that even if they hear things through their own
personal experiments "they are hearing nothing", why - because you said so.
Were you there? No. Do you care? No. What do you do with your friends - preach
at them? What do you do with your clients - tell them how wonderful you are?
What do you do with your children - chastise them for their incompetence?
Haven't you noticed that something is wrong in all this? Hasn't it ocurred to
you to LISTEN to people, to keep an open mind, to laugh with others, not at
them? Hasn't it occurred to you to PRAISE others from time to time for their
enthusiasm and joyous spirit of discovery? Let me tell you something - I go to
group therapy every week. I don't need it. I go because I want to be able to
listen to others, be sensitive to others and check how I come across to others.
I'm not proud - like all of us I'm simply human. But I do very much value the
people I share the world with and I do NOT go around calling them stupid.

=== Andy Evans ===
Visit our Website:- http://www.artsandmedia.com
Audio, music and health pages and interesting links.