Advice: Amp building
 

Arny Krueger wrote:
"Rob" wrote in message
...
Jim Lesurf wrote:

Maybe, but you wouldn't necessarily end up with a very good, or
consistently quick, car.

That's a false criteria, because many people use similar techniques and
tools to optimize race cars and drivers, and some end up with good ones and
some end up with also-rans. Furthermore, the winners and losers often
interchange roles on a weekly, monthly, and yearly basis.


Uh - criteria are criteria. But yes, i agree.

For example, Jeff Gordon last year and this year. For example Jeff Gordon
last Sunday and about a month ago at the same track - Pocono.

When a whole industry changes from tubes to SS, it reflects positively on
the benefits of the new technology.

When the whole art of racing changes from hihgly subjective evaluation
techniques to the current heavy reliance on objective evaluation techniques,
it reflects positively on the benefits of the new technology.


I don't agree. The technology is led by the tobacco and petrochemical
industries from what little I see and know. Now the art *and* science of
motor racing (and indeed audio) is something I'm interested in, but I
can't see it getting many ng inches here at least. Can you explain in
scientific terms why Schumacher (say, erm Michael) drives cars faster
than anyone else? I would wager that his car is set up in some very
peculiar ways, as his team techs see it.

People who don't study and learn from history just keep making the same
mistakes over and over again.


Well, you know of course, it tends to go first as tragedy, second as
farce. But that's just how people interpret history - you have your
lens, I have mine.

Rob

Advice: Amp building
 

Keith G wrote:
"Wally" wrote in message
...
Don Pearce wrote:

... Now things like SETs do exactly that, and hence it is hard to
figure how they might merit a word like "best".
It's obvious: different people have different criteria for what they
*like*.
"Best" doesn't neccessarily mean best within certain technical criteria to
do with some notion referred to as 'accuracy of reproduction'. So far as I
understand it, listening to music isn't about some abstract, and
ultimately
unobtainable, 'accuracy', it's about what you *feel* when you listen to
it.


The problem here is that some people like Don are conditioned by their
training and experience to *know* a SET can't be right (on paper), the
simple fact remains *for me* that (to put it very simply, by way of
illustration) if I swap from a SET to an 'ordinary PP valve amp' I am *not*
uplifted and if I swap from a SET to an SS amp I am quite 'disappointed' and
can not really get confortable with the sound.

snip


OK, quite by chance (I didn't take both these pix) I have what I think is a
good analogy for what I perceive to be the difference between analogue and
digital, valves and SS. See these very similar pix:

http://www.apah69.dsl.pipex.com/show...Screenshot.jpg

http://www.apah69.dsl.pipex.com/show...Screenshot.jpg

They are both handheld snaps of virtually the same frame from the same film
film - one from a DLP projector and one from an LCD projector.

Initially, the DLP image doesn't strike you as sharp as that from the LCD
and DLP projectors suffer from 'artifacts' that are not present with LCD.
Also the DLP projector is noisier, runs hotter and is much bigger than the
LCD. If you have not seen a DLP projector and only use an LCD one, it will
satisfy you completely and they are very easy and convenient to use.

On paper the case for the LCD is strong, in reality the DLP ****es all over
it....


I think that works pretty well. Over on the digital tv ng (where DP is
sweetness and light!) you wouldn't believe the evangelism that goes with
the CRT/LCD/plasma etc debate (well, you would), all backed up with some
stonking technobabble. Understanding that 'preference counts' causes all
sorts of difficulties.

Rob

Advice: Amp building
 

"Rob" wrote in message
...

I don't agree. The technology is led by the tobacco and petrochemical
industries from what little I see and know. Now the art *and* science of
motor racing (and indeed audio) is something I'm interested in, but I
can't see it getting many ng inches here at least. Can you explain in
scientific terms why Schumacher (say, erm Michael) drives cars faster than
anyone else? I would wager that his car is set up in some very peculiar
ways, as his team techs see it.



Michael Schumacher has judgement and reflexes that, on a good day, give him
an edge on his opposition. The team is at the forefront of the sport with
much money to spend to assist in maintaining that position. Team techs are
not there to set the car up in any non-peculiar ways, they are there to make
adjustments that result in faster lap times while maintaining reliability
and keeping the relevant stresses and wear rates within what are determined
to be acceptable limits for the event. In lower levels of competition you do
get drivers with undesirable driving techniques who require the car to be
set up in "peculiar ways" for them to achieve their fastest times, however,
these drivers are typically not competative in the highest levels of racing.

Advice: Amp building
 

In article .com,
Andy
Evans wrote:
We have low cost high volume production amps that exceed any reasonable
need. AK

OK - so the 'need' for a reference system, e.g. for professional
musicians, that is better than high volume production ss amps is
"unreasonable".

Amps are only useful and interesting as components of more complex
systems, they are almost completely disinteresting as ends in
themselves. AK

So why do you and Jim (DHTs) insist on pontificating over componants
which you have no interest in?

You seem to have a base-apex confusion. The recent history is that you were
'pontificating'[1] about DHTs and I asked you if you could provide some
evidence or explanation.

My 'interest' was that I was curious to see what might cause a DHT to
produce the sonic differences you were asserting. IIRC You then failed to
give any plausible physical explanation or any assessible evidence that
there was a real audible difference.

Fortunately, Nick *did* make some useful comments on the issue that may be
relevant. So he did attempt to answer the questions. What he wrote seems
quite plausible to me, but IIRC no-one offerred any specific evidence to
support your assertion that this *did* have an audible effect.

Unfortunately, Andy, you then interpreted my questions, and my noting
that you had not provided any assessable evidence as if it were a
personal attack on you. I regret that, however I have a habit of trying
to consider evidence when I can, not simply accept what I am told to
believe, by you or anyone else. I am sorry if this annoys you.

As I said previously, I can see no reason to claim that DHTs *can't*
affect the sound. It seems quite plausible that they might, depending
on the details of how they are used. The problem is that I've seen no
reliable evidence of this.


Slainte,

Jim

[1] If you look up 'pontificate'or 'pontificating' in a dictionary
you find that it essentially means making statements that you
expect others to accept simply on the basis that you are an
'authority' that cannot be questioned. Andy made the statement
asserting that DHTs affected the sound. I asked for some
evidence or explanation to support his assertions. Asking
someone for an explanation or evidence so you can judge
for yourself isn't what I'd normally call 'pontificating'.
Making statements and expecting people to accept them without
any evidence seems more like it to me. :-)


--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html

Advice: Amp building
 

On Fri, 28 Jul 2006 21:34:53 GMT, "Arfa Daily"
wrote:


"Don Pearce" wrote in message
...
On 27 Jul 2006 07:17:43 -0700, "Andy Evans"
wrote:

You make one change and measure - if it is better,
go a bit further until you peak. Then you start on the next parameter
and do it again. Once everything is as good as it gets, you go back to
the beginning and start again because everything interacts. Some
parameters you adjust in pairs because the interaction is first order
A bit like amplifier development in some ways.

This is a succinct, informative and practical explanation of product
development, and it sounds a hell of a lot like amplifier development
to me. You obviously have the benefit of experience here - from what
you say a lot of your work was extremely practical and solution
orientated in nature (and include the hard climates and adverse
circumstances.....!!!) Andy.

Yup that was way back when. It was all a bit more demanding than
amplifier development though. I was designing microwave and RF
measuring instruments for Marconi Instruments. The requirements were
many tens of dBs better than anything audio demands. The iterative
process was frequently something like 10 micron increments in the
length of a track connecting a FET gate. I would build a bunch at once
with all the different lengths, then evaluate them.

d

Don.
Do you know a guy called Peter Spurr from your Macaroni Inst days ??

Arfa


Sorry - doesn't ring bells. I was working at the new labs at
Stevenage. He may well have been at St. Albans.

d

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

Advice: Amp building
 

"Don Pearce" wrote in message
...
On Fri, 28 Jul 2006 21:34:53 GMT, "Arfa Daily"
wrote:


"Don Pearce" wrote in message
...
On 27 Jul 2006 07:17:43 -0700, "Andy Evans"
wrote:

You make one change and measure - if it is better,
go a bit further until you peak. Then you start on the next parameter
and do it again. Once everything is as good as it gets, you go back to
the beginning and start again because everything interacts. Some
parameters you adjust in pairs because the interaction is first order
A bit like amplifier development in some ways.

This is a succinct, informative and practical explanation of product
development, and it sounds a hell of a lot like amplifier development
to me. You obviously have the benefit of experience here - from what
you say a lot of your work was extremely practical and solution
orientated in nature (and include the hard climates and adverse
circumstances.....!!!) Andy.

Yup that was way back when. It was all a bit more demanding than
amplifier development though. I was designing microwave and RF
measuring instruments for Marconi Instruments. The requirements were
many tens of dBs better than anything audio demands. The iterative
process was frequently something like 10 micron increments in the
length of a track connecting a FET gate. I would build a bunch at once
with all the different lengths, then evaluate them.

d

Don.
Do you know a guy called Peter Spurr from your Macaroni Inst days ??

Arfa


Sorry - doesn't ring bells. I was working at the new labs at
Stevenage. He may well have been at St. Albans.

He was definitely at Stevenage for a time, but that might have been after it
was taken over by (IFW was it ?) I'll have to ask him. I just thought that
the u-wave test instruments design fraternity was quite small and having
both been with Marconi, that you might have known one another.

Arfa

Advice: Amp building
 

On Sat, 29 Jul 2006 03:35:09 +0100, "Keith G"
wrote:


"Wally" wrote in message
...
Don Pearce wrote:

... Now things like SETs do exactly that, and hence it is hard to
figure how they might merit a word like "best".

It's obvious: different people have different criteria for what they
*like*.
"Best" doesn't neccessarily mean best within certain technical criteria to
do with some notion referred to as 'accuracy of reproduction'. So far as I
understand it, listening to music isn't about some abstract, and
ultimately
unobtainable, 'accuracy', it's about what you *feel* when you listen to
it.


The problem here is that some people like Don are conditioned by their
training and experience to *know* a SET can't be right (on paper), the
simple fact remains *for me* that (to put it very simply, by way of
illustration) if I swap from a SET to an 'ordinary PP valve amp' I am *not*
uplifted and if I swap from a SET to an SS amp I am quite 'disappointed' and
can not really get confortable with the sound.


Keith you say I am conditioned by my training and experience - but you
are too, you know. You have just ended up in a different place. You
think your place is better (well, you'd have to really), and I think
that my place is. The difference in our two "places" is that mine will
allow a far wider range of possibilities in what it presents to me,
because it is not overlaid with a systematic "sound" produced by the
deliberate bending of the signal from devices like SETs - and I'm not
going to allow you to argue that one, because it is objectively
demonstrable, and nothing to do with opinion. I've made the analogy
before of viewing the world through tinted glasses (the SET world). It
may be pretty for a while, but I would want to take them off and see
ALL the colours, not just the ones boosted by the tint.

I use SS amps all the time - excellent for AV/telly and 'background sound'
throughout the house during the day, but I do not *prefer* them.

Keep working at it - you'll come over from the dark side eventually
:-)



It would seem that the definition of "best" being promulgated by certain
individuals rests in their presupposition that the 'accurate' approach to
reproducing sound is the *only* way to acheive this. This is the false
premise that I said Dave was proceeding from. To wit...

This means LP is *adding* something to the audio that it shouldn't.

Who says that something shouldn't be added? Where is the universal truth
upon which this assertion is predicated? There is none. It is predicated
on
the supposition that use of audio equipment which doesn't 'add' something
is
the only way to instill whatever it is that we seek to feel when listening
to music.


Plowie's problem is that admitting vinyl is *adding* something to the sound
is some sort of shibboleth that he needs to hear. What he doesn't know (or
want to know) is that I and a number of others don't much care whether it is
or not. I (and I suspect a number of others) feel that all the equipment
alters the sound and the end product, which is is the ultimate goal, is the
sum of all the components and source material used.

It is the glasses again. WIth vinyl not only do you have the tint, but
the glass is a bit wavy too. Great fun - a bit like one of those
distorting mirror halls. And you are wrong about all equipment
altering sound; the good stuff genuinely doesn't - it will preserve
the sound from end to end. The equipment you prefer does alter the
sound, of course, but somehow it all ends up in a place you like. I'm
at a bit of a loss to understand how that happens, because all the
alterations are different, and you would have thought that with each
one it was fifty-fifty whether it got "better" or "worse" to your
ears. I think the truth has to be that you simply like the fatter,
more "in your face" sound of the lightly distorted system. And that is
fair enough - but it isn't what most denizens of these groups are
looking for, and to describe it in terms like "better", that in
technical circles have objective meanings far removed from what you
are describing is bound to raise hackles.


Err, no. It was an example of how your whole thinking is flawed.

LIS, the *only* way: "Think like me, or you're wrong".



That's Plowie - see other recent posts. You can't ever win with him - ignore
him and he'll call you a ******, respond to his bigotted remarks and he
tries to play you like you're lucky to get an acknowledgement. Personally,
I've no idea why he bothers to subscribe here, there don't seem to be much
that pleases him...??



You
are looking for an extremely coloured unnatural sound - ...

Keith has made it clear for at least two or three years that what he's
after
from his kit is that it has to instill the right emotional response.
Dave's
comment is not based on what Keith has said - it's baseless.


OK, I think I can help out here - see below for an analogy....




That use of words
gets up some people's noses, particularly when it is directed at a
newbie who is seeking guidance in Hi Fi. I can see why.


Don's words I think - no idea why he says that, I've never 'advised' a
newbie to do anything other than grab cheap (but good) off eBay until
recently now that Arny's 'low rent, adequate' stuff is down to damn near
eBay prices! (My last purchases for 'ordinary, thrasher' kit have all been
from Argos and Lidls...??!!)

No it isn't in the form of advice - but you do tend to use such
adjectives in such threads, and that makes them advice whether you
like it or not. The problem is that they need to be caveated by a
government health warning "I think this is better, but I'm from St.
Neots and well, you know how it is" :-)

OK, quite by chance (I didn't take both these pix) I have what I think is a
good analogy for what I perceive to be the difference between analogue and
digital, valves and SS. See these very similar pix:

http://www.apah69.dsl.pipex.com/show...Screenshot.jpg

http://www.apah69.dsl.pipex.com/show...Screenshot.jpg

They are both handheld snaps of virtually the same frame from the same film
film - one from a DLP projector and one from an LCD projector.

Initially, the DLP image doesn't strike you as sharp as that from the LCD
and DLP projectors suffer from 'artifacts' that are not present with LCD.
Also the DLP projector is noisier, runs hotter and is much bigger than the
LCD. If you have not seen a DLP projector and only use an LCD one, it will
satisfy you completely and they are very easy and convenient to use.

On paper the case for the LCD is strong, in reality the DLP ****es all over
it....


The DLP is hugely better, looking at those photos. The LCD has a green
cast to it. For me none of these technologies has yet reached the
point where I would be prepared to spend any of my own money on them.
And the clearer they get, the worse they get - all I see is pixels,
and they just aren't entertaining. For me those pixels represent the
kind of visibility in the output of the internal technology that you
get with SET, vinyl etc, so you are right - the analogy does hold to a
limited extent. With SS and digital, none of that stuff shows - it is
all smooth.

d

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

Advice: Amp building
 

On Sat, 29 Jul 2006 07:55:54 GMT, "Arfa Daily"
wrote:

Don.
Do you know a guy called Peter Spurr from your Macaroni Inst days ??

Arfa


Sorry - doesn't ring bells. I was working at the new labs at
Stevenage. He may well have been at St. Albans.

He was definitely at Stevenage for a time, but that might have been after it
was taken over by (IFW was it ?) I'll have to ask him. I just thought that
the u-wave test instruments design fraternity was quite small and having
both been with Marconi, that you might have known one another.

Arfa


Yes - that was well after I left. IFR was the company, but it has
since changed again. I quit that part of the industry completely when
I left, although I do still know a couple of the chaps from there.

d

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

Advice: Amp building
 

Hello Dave - I'd probably agree with you that detail and clarity are
pretty much the same, AE

Nope. A lack of treble might result in the loss of detail but it won't
necessarily
mean there is no clarity - Kieth

thinking about it again, I'd say "detail" might apply to a small sound
which may or may not be audible, could be masked as you say by a
falling response. Clarity I think of as clear textures, without
blurring, very much like distortion tests for SLR lenses ~(e.g. if
you're old enough to remember the AP tests of that warship in the
Thames) ~ where stopped down there is better resolution and textures
are much clearer without blurring. I suppose if we keep the analogy
then timbre is the quality of the textures themselves together with
faithfullness of colour.

Developing your system is a lot like an eye test. You use the same
reference (PQXZT or whatever it is) and then chose the better
alternative in each pair through a number of iterations. Result - you
get a pair of glasses. Yet another practical example of how people
develop thinks in real life and get acceptable results. You only have
your eyes to rely on for the choices you make, but then you only use
the result - your glasses - with those same eyes. If you evaluate your
system with your ears and then listen to the results, is this so very
different?

Advice: Amp building
 

Keep working at it - you'll come over from the dark side eventually
(DP)

All you need to convince Keith is fear, surprise, ruthless efficiency,
an almost fanatical devotion to the transistor, and nice red uniforms