Russ Andrews and Ben Duncan :-)
 

"Keith G" wrote in message
...


The single strand is nothing to do with fuses (what's the whole wire
then - a *higher rated fuse*?) - it was merely to illustrate the point
that I believe 'conventional wisdom' actually promotes and encourages
'snake oil' (referenced in the OP) by doing something rather
unconventional....


I wondered what on earth you thought your "single strand of wire"
demonstrated; and your "explanation" above does little to clarify the point.
Quite *how* you think that " 'conventional wisdom' actually promotes and
encourages 'snake oil" is a mystery that is unlikely ever to be solved.

David.

Russ Andrews and Ben Duncan :-)
 

In article 4a400810.843208703@localhost, Don Pearce
wrote:
On Mon, 22 Jun 2009 18:43:01 +0100, Jim Lesurf
wrote:
[snip]

So my feeling is that the systematic fall - essentially common to all
the cables - is an instrumental/measurement effect outwith the cables
under test.


True. Maybe something to do with the fixtures.

Indeed. That is what I am wondering about. I am also wondering why the
results seem to show such a *lack* of mismatch to the '50 Ohm' source and
load. This seems quite an odd coincidence, but may just be because most
normal cables aren't that different to 50 Ohms-ish.

I also have the feeling that your explanation would not explain the
extent of the reduction, nor why all the cables seem to show it to much
the same extent. For example, if - as seems likely - the fancy cables
have a lower impedance then the field has a different E/H ratio. The
dielectric will affect the E-field losses, not the H-field. Again it
seems a curiously odd coincidence if that balanced perfectly at all
frequencies with, say, resistive conduction losses. Making all the
losses for the peaks against frequency come out much the same for all
frequencies seems an odd coincidence to me.


Puzzling indeed. I think perhaps the loss has more to do with radiation
than absorption.

Again, curious that all cables show it to much the same extent. I need to
read the full papers again, but I am curious about two issues. One is the
construction of the units used to couple source and load. The other is how
the system was actually calibrated. Simple getting a decent response with a
50 Ohm co-ax isn't 'calibration'. I also am wondering how the levelling was
actually done, and how the effects of that were calibrated.

However I need to re-read the detailed papers a few times and think
about them. My feeling, though is that all the results in the initial
pdf show is that the cables have different Zc values. The relevant
measurements seem to have been done with no mains supply or loading
PSU. Just with what seem to be claimed to be 50Ohm terminations.

My thoughts exactly. The source impedance should be whatever you get
from a few miles of twin coupled to a transformer, a few thousand light
bulbs, a bunch of motors, many TVs and loads of fluorescents. That
shouldn't be too hard to model ;-)

....but possible to measure. :-)

The sensible thing would be to have made up a mains-safe highpass rf
connection and then use the 50Ohm (?) analyser to measure the reflection
coefficient of a few typical domestic mains sockets. From this you can then
at least infer values for the typical/likely source impedance they present
at RF.

As for the load. That will vary from minor conduction on peaks when the
audio is quiet, to extended conduction up the leading edges when it is
loud. And of course the conducting phase will be dumping straight into a
big capacitor. I can see why they went for 50 ohms, even if it is
nonsense.

I can understand the wish to make measurements as easy and simple as
possible. Particularly when time is money. However the snag is to avoid
making them so 'simple' that they cease to be relevant to the real-world
situation which you want to use the 'results' to describe. :-)

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

Russ Andrews and Ben Duncan :-)
 

In article , Eeyore
wrote:


Jim Lesurf wrote:

My concern isn't with the personalities, nor with the way any of us
can make a simple mistake.

I think you mean deliberate mistake or deception. I could elaborate.

No. I am unable to say that there is any deliberate or knowing deception.

It is one thing to decide if the measurements do support their claims or
not. And to decide if the results are due to inappropriate measurements
techniques or other technical errors, or not. I, and others, can form a
view on that by applying normal scientific and engineering methods to the
published information.

It is something else to decide that they *know* their claims are false and
that the evidence is deliberately and consciously bogus. I can't say that
from reading the presented evidence. People believe all kinds of things
which seem like rubbish to me, and to err is human.

So my concern here is as I stated above, and that others should be able to
correctly assess the evidence, not the personalities. If someone else has
evidence of deliberate deception, then they should present it to the ASA or
others who may be relevant. I have no such evidence.

Of course, you can 'elaborate' if you so choose, but I could not possibly
comment. :-)

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

Russ Andrews and Ben Duncan :-)
 

On Tue, 23 Jun 2009 09:45:32 +0100, Jim Lesurf
wrote:

In article 4a400810.843208703@localhost, Don Pearce
wrote:
On Mon, 22 Jun 2009 18:43:01 +0100, Jim Lesurf
wrote:
[snip]

So my feeling is that the systematic fall - essentially common to all
the cables - is an instrumental/measurement effect outwith the cables
under test.


True. Maybe something to do with the fixtures.

Indeed. That is what I am wondering about. I am also wondering why the
results seem to show such a *lack* of mismatch to the '50 Ohm' source and
load. This seems quite an odd coincidence, but may just be because most
normal cables aren't that different to 50 Ohms-ish.

I also have the feeling that your explanation would not explain the
extent of the reduction, nor why all the cables seem to show it to much
the same extent. For example, if - as seems likely - the fancy cables
have a lower impedance then the field has a different E/H ratio. The
dielectric will affect the E-field losses, not the H-field. Again it
seems a curiously odd coincidence if that balanced perfectly at all
frequencies with, say, resistive conduction losses. Making all the
losses for the peaks against frequency come out much the same for all
frequencies seems an odd coincidence to me.


Puzzling indeed. I think perhaps the loss has more to do with radiation
than absorption.

Again, curious that all cables show it to much the same extent. I need to
read the full papers again, but I am curious about two issues. One is the
construction of the units used to couple source and load. The other is how
the system was actually calibrated. Simple getting a decent response with a
50 Ohm co-ax isn't 'calibration'. I also am wondering how the levelling was
actually done, and how the effects of that were calibrated.


If I were trying to analyse the response of a random, unknown piece of
cable, the first thing I would do is find out its impedance by a
simple jX test on an eighth wave piece hanging off a network analyser.
The fixture would then be designed to transform the 50 ohms to that
impedance (at both ends). Only then could I make a measurement free
from the stupid VSWR leaps. Actually, these days I suppose the
impedance transformation could be done in software after the event,
but that is by the by.

As for calibration, I would want to de-embed the fixtures by making up
open, short and load calibration pieces that plugged in where the
actual cable went. Tricky, I know, but for results up to a few hundred
megs I would be reasonably happy with the results.

For the "through" calibration I would make sure the mains lead had
male and female versions of the same connector both ends, and simply
plug the fixtures together - that would make for an insertable
calibration, which is always the safest.

Thinking about this, I can find no earthly reason for that BNC curve
to be presented. Do you have any idea what purpose it serves?

However I need to re-read the detailed papers a few times and think
about them. My feeling, though is that all the results in the initial
pdf show is that the cables have different Zc values. The relevant
measurements seem to have been done with no mains supply or loading
PSU. Just with what seem to be claimed to be 50Ohm terminations.

My thoughts exactly. The source impedance should be whatever you get
from a few miles of twin coupled to a transformer, a few thousand light
bulbs, a bunch of motors, many TVs and loads of fluorescents. That
shouldn't be too hard to model ;-)

...but possible to measure. :-)


Perhaps they could go to every potential customers house and measure
it, then produce a curve of probable improvement...

The sensible thing would be to have made up a mains-safe highpass rf
connection and then use the 50Ohm (?) analyser to measure the reflection
coefficient of a few typical domestic mains sockets. From this you can then
at least infer values for the typical/likely source impedance they present
at RF.

As for the load. That will vary from minor conduction on peaks when the
audio is quiet, to extended conduction up the leading edges when it is
loud. And of course the conducting phase will be dumping straight into a
big capacitor. I can see why they went for 50 ohms, even if it is
nonsense.

I can understand the wish to make measurements as easy and simple as
possible. Particularly when time is money. However the snag is to avoid
making them so 'simple' that they cease to be relevant to the real-world
situation which you want to use the 'results' to describe. :-)


Who was it who said that in science everything should be described as
simply as possible - but no simpler.

d

Russ Andrews and Ben Duncan :-)
 

In article ,
Keith G wrote:
It really depends on the speakers. amps and level you use. I was
merely trying to explain to Kitty that a short length of single strand
wire might well not make any audible difference under some
circumstances. But might well under others.



Ooh dear - after getting his knickers all twisted up about 'fuses' and
trying to bull**** his way out of a tight spot, Poochie's trying to
change tack fast and is reduced to bare-faced lies now...???

Jesus you're thick. A short length of thin wire in a run of thicker is
*exactly* what a fuse is. And makes no difference to the performance of
that circuit until certain parameters are exceeded.

--
*If I worked as much as others, I would do as little as they *

Dave Plowman London SW
To e-mail, change noise into sound.

Russ Andrews and Ben Duncan :-)
 

In article ,
David Looser wrote:
"Keith G" wrote in message
...


The single strand is nothing to do with fuses (what's the whole wire
then - a *higher rated fuse*?) - it was merely to illustrate the point
that I believe 'conventional wisdom' actually promotes and encourages
'snake oil' (referenced in the OP) by doing something rather
unconventional....


I wondered what on earth you thought your "single strand of wire"
demonstrated; and your "explanation" above does little to clarify the
point. Quite *how* you think that " 'conventional wisdom' actually
promotes and encourages 'snake oil" is a mystery that is unlikely ever
to be solved.

Kitty is forever trying to re-invent the wheel. Dunno why he thought
adding a very small series resistance to a speaker circuit would make
things sound different. But judging by the jump leads melting story, he
needs to re-invent Ohms law too...

David.

--
*All generalizations are false.

Dave Plowman London SW
To e-mail, change noise into sound.

Russ Andrews and Ben Duncan :-)
 

"TT" wrote in message
. au...

"Keith G" wrote in message
...

"Pheel My Arsehole" wrote
A whole lot of rubbish which I snipped unread.

Bored now....

BTW when Philthy repeats or just cuts 'n' pastes you know you have done
him cold ;-)

Keep up the good work :-)

Cheers TT



Wiser people than me ignore him and some people here *avoid him* because,
when it comes down to it on a 'technical front', he could eat them for
breakfast. (They know who they are. ;-)

On his more *lucid* days, needless to say....

Dear Jim...
 

"Jim Lesurf"


** Dear Jim,

you are one of the most totally ****ed in the head, retarded autistic
pukes alive in the UK

- and that is saying something - cos the whole stinking **** hole is just
crawling with them.

People like YOU constitute a serious public menace, for the sole reason
that you are so damn ****ing STUPID.

Not a damn thing you can do about THAT - of course.

But beware, there is plenty OTHERS can do about YOU !!!

The terminally stupid in society cause FAR FAR more trouble than all the
nutters and psychos put together.

Please please please, for the benfit of humanity

get very ill - very soon and ****ing die.




...... Phil

Russ Andrews and Ben Duncan :-)
 

"Jim Lesurf"


** Dear Jim,

you are one of the most totally ****ed in the head, retarded autistic
pukes alive in the UK - and that is saying something - cos the whole
stinking **** hole is just crawling with them.

People like YOU constitute a serious public menace, for the sole reason
that you are so damn ****ing STUPID.

Not a damn thing you can do about THAT - of course.

But beware, there is plenty OTHERS can do about YOU !!!

The terminally stupid in society cause FAR FAR more trouble than all the
nutters and psychos put together.

Please please please, for the benfit of humanity

get very ill - very soon and ****ing die.





...... Phil

Russ Andrews and Ben Duncan :-)
 

"Jim Lesurf"

** Dear Jim,

you are one of the most totally ****ed in the head, retarded autistic
pukes alive in the UK - and that is saying something - cos the whole
stinking **** hole is just crawling with them.

People like YOU constitute a serious public menace, for the sole reason
that you are so damn ****ing STUPID.

Not a damn thing you can do about THAT - of course.

But beware, there is plenty OTHERS can do about YOU !!!

The terminally stupid in society cause FAR FAR more trouble than all the
nutters and psychos put together.

Please please please, for the benfit of humanity

get very ill - very soon and ****ing die.




...... Phil