I got my latest copy of 'Stereophile' yesterday and started to read it. I
came across comments by Paul Messenger about some work that Russ
Andrews and Ben Duncan have recently put onto the web. This seems to be
taken by Paul Messenger as showing that Russ's claims re some of his
products are "now supported by proper scientific analysis".

But having looked at

http://www.russandrews.com/downloads...estPremRes.pdf

[above file size 700K]

I can't say I agree with that belief simply on the basis of what the above
contains. But that may in part be because I've examined a past set of
measurements by Ben Duncan and come to rather different conclusions to the
ones he and a co-author asserted about them at the time.[1] I would
therefore like to know all the measurement systems/proceedure details that
are sadly omitted from the above.

I thought others here might be interested to read the above pdf and
consider it for themself.

I am curious to know if the reactions of others agree with my own. In
particular, if others can spot 'The dog that did not bark in the night'.
:-)

Enjoy,

Jim

[1] See
http://www.st-andrews.ac.uk/~www_pa/...eshift/cp.html

--
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

On Sun, 21 Jun 2009 09:03:51 +0100, Jim Lesurf
wrote:

I got my latest copy of 'Stereophile' yesterday and started to read it. I
came across comments by Paul Messenger about some work that Russ
Andrews and Ben Duncan have recently put onto the web. This seems to be
taken by Paul Messenger as showing that Russ's claims re some of his
products are "now supported by proper scientific analysis".

But having looked at

http://www.russandrews.com/downloads...estPremRes.pdf

[above file size 700K]

I can't say I agree with that belief simply on the basis of what the above
contains. But that may in part be because I've examined a past set of
measurements by Ben Duncan and come to rather different conclusions to the
ones he and a co-author asserted about them at the time.[1] I would
therefore like to know all the measurement systems/proceedure details that
are sadly omitted from the above.

I thought others here might be interested to read the above pdf and
consider it for themself.

I am curious to know if the reactions of others agree with my own. In
particular, if others can spot 'The dog that did not bark in the night'.
:-)

Enjoy,

Jim

[1] See
http://www.st-andrews.ac.uk/~www_pa/...eshift/cp.html

Interesting. The big problem here is that they were measuring the
wrong thing. They should have been measuring effects at speaker
terminals, not on power rails. My intuition tells me that the audible
difference between 80 and 90 dB of attenuation at the power rails is
going to be close to zero. After all, you must add to that the CMRR,
which is already going to be the right side of 100dB, so effectively
we are talking the difference between -180 and -190. Both of these are
altogether huge compared to what is actually needed.

Add to that the idea that 1000V spikes are common enough occurrences
that they impinge on your day to day listening, (rather than being a
"bugger me, what was that?" moment as half the fuses in the house
blow), and require dealing with for listening pleasure.

Of course, if this were a single ended valve amp with no intrinsic
power supply rejection, there might be a case to be made.

d

"Don Pearce" wrote in message
news:4a3dec21.704992218@localhost...
On Sun, 21 Jun 2009 09:03:51 +0100, Jim Lesurf
wrote:

I got my latest copy of 'Stereophile' yesterday and started to read it. I
came across comments by Paul Messenger about some work that Russ
Andrews and Ben Duncan have recently put onto the web. This seems to be
taken by Paul Messenger as showing that Russ's claims re some of his
products are "now supported by proper scientific analysis".

But having looked at

http://www.russandrews.com/downloads...estPremRes.pdf

http://www.st-andrews.ac.uk/~www_pa/...eshift/cp.html

Interesting. The big problem here is that they were measuring the
wrong thing.

Excellent point.

They should have been measuring effects at speaker
terminals, not on power rails.

Notably, power rails before regulation.

I'll take that as a tacit admission that the regulator made a big
difference, even a bigger difference.

Actually I don't need to get any admissions from them at all, making a big
difference is what regulators do!

My intuition tells me that the audible
difference between 80 and 90 dB of attenuation at the power rails is
going to be close to zero.


Exactly. Furthermore, the fact that their product only made a 10 dB
difference is a clear denounciation of their product.

After all, you must add to that the CMRR,
which is already going to be the right side of 100dB, so effectively
we are talking the difference between -180 and -190. Both of these are
altogether huge compared to what is actually needed.

Also note that the stimulus they were using was a 500 volt peak spike. Ever
see such a thing on a real world power line? Well, maybe once in a blue
moon.

Add to that the idea that 1000V spikes are common enough occurrences
that they impinge on your day to day listening, (rather than being a
"bugger me, what was that?" moment as half the fuses in the house
blow), and require dealing with for listening pleasure.

Agreed.

Of course, if this were a single ended valve amp with no intrinsic
power supply rejection, there might be a case to be made.

Of course they make no admissions that one has to have a stupidly designed
amp for there to be any possible audible benefit at all, except when the
moon is blue! ;-)

Arny Krueger wrote:

Also note that the stimulus they were using was a 500 volt peak spike. Ever
see such a thing on a real world power line? Well, maybe once in a blue
moon.

I suppose they haven't heard of Varistors !

Graham

due to the hugely increased level of spam please make the obvious adjustment to
my email address

On Sun, 21 Jun 2009 09:03:51 +0100, Jim Lesurf
wrote:

I got my latest copy of 'Stereophile' yesterday and started to read it. I
came across comments by Paul Messenger about some work that Russ
Andrews and Ben Duncan have recently put onto the web. This seems to be
taken by Paul Messenger as showing that Russ's claims re some of his
products are "now supported by proper scientific analysis".

But having looked at

http://www.russandrews.com/downloads...estPremRes.pdf

[above file size 700K]

I can't say I agree with that belief simply on the basis of what the above
contains. But that may in part be because I've examined a past set of
measurements by Ben Duncan and come to rather different conclusions to the
ones he and a co-author asserted about them at the time.[1] I would
therefore like to know all the measurement systems/proceedure details that
are sadly omitted from the above.

I thought others here might be interested to read the above pdf and
consider it for themself.

I am curious to know if the reactions of others agree with my own. In
particular, if others can spot 'The dog that did not bark in the night'.

From the preamble:
"...we set about conducting a series of robust
scientific tests to back up the claims we have always made
for our products’ abilities."

He doesn't know the difference between science and theology. Do we
really need to read further?

On Sun, 21 Jun 2009 11:28:31 +0100, Laurence Payne
wrote:

On Sun, 21 Jun 2009 09:03:51 +0100, Jim Lesurf
wrote:

I got my latest copy of 'Stereophile' yesterday and started to read it. I
came across comments by Paul Messenger about some work that Russ
Andrews and Ben Duncan have recently put onto the web. This seems to be
taken by Paul Messenger as showing that Russ's claims re some of his
products are "now supported by proper scientific analysis".

But having looked at

http://www.russandrews.com/downloads...estPremRes.pdf

[above file size 700K]

I can't say I agree with that belief simply on the basis of what the above
contains. But that may in part be because I've examined a past set of
measurements by Ben Duncan and come to rather different conclusions to the
ones he and a co-author asserted about them at the time.[1] I would
therefore like to know all the measurement systems/proceedure details that
are sadly omitted from the above.

I thought others here might be interested to read the above pdf and
consider it for themself.

I am curious to know if the reactions of others agree with my own. In
particular, if others can spot 'The dog that did not bark in the night'.

From the preamble:
"...we set about conducting a series of robust
scientific tests to back up the claims we have always made
for our products’ abilities."

He doesn't know the difference between science and theology. Do we
really need to read further?

I just looked at the last bit - the measurements. I know the Cyrus II
very well (I have one), and its distortion characteristic is the same
as every other amplifier on the planet - it rises at high frequency.
According to his measurement it falls. That is actually a quite
embarrassing article.

Peer review will either be revealing or not. If his peers are anything
like him in ability, it will presumably pass.

d

In article , Laurence Payne
wrote:
On Sun, 21 Jun 2009 09:03:51 +0100, Jim Lesurf
wrote:


I am curious to know if the reactions of others agree with my own. In
particular, if others can spot 'The dog that did not bark in the
night'.

From the preamble: "...we set about conducting a series of robust
scientific tests to back up the claims we have always made for our
products abilities."

He doesn't know the difference between science and theology. Do we
really need to read further?

Yes, the preamble, etc, do indicate that the tests may have been done on a
different basis to the scientific approach. The aim seems to have been,
"find some results that support what we think is the case". Whereas a
scientific experiment would have been, "Devise a test whose outcome will
distinguish between our idea being correct, or it being unreliable".

However I do think it is worth reading further for two reasons.

One is that ceasing to read, and not bothering to think about what they
report would abdicate from being able to comment on the actual results.

The second is that considering what they report does perhaps show some
other things. e.g. 'the dog' I referred to. As with the older case I used
as a footnote, sometimes published results give clues to what may have been
problems with the measurement process, or at least make clear that -
without more info which is presently witheld - the results can't be shown
to establish the conclusions they (and Paul Messenger) presume. They may
arise for other fairly simple reasons.

FWIW I have emailed the contact they give, asking for more info. But I have
no idea as yet if I will get a useful response. Until then, I can only have
doubts about the 'measured results' since data can only be understood when
you know all the relevant details of how it was obtained. The present pdf
simply doesn't give the required details.

WRT to 'the dog' I can ask two questions of people. Can you explain why the
cables that are claimed to be 'better' exhibit the frequency dependence
that they graphs show? Then ask, why does the 'BNC' cable not also show
this? The answers may tell us something interesting about the measurement
setup used... and the unspecified assumptions those reporting the
measurements may have made. :-)

If unsure, consider the setup error which was made in the previous case
which I used as a footnote. ;-

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

"Laurence Payne"

From the preamble:
"...we set about conducting a series of robust
scientific tests to back up the claims we have always made
for our products' abilities."

He doesn't know the difference between science and theology. Do we
really need to read further?

** Nope.

Your quote above reminds me of a line spoken in numerous B grade Western
movies:

A fat ugly guy, with a rope noose ready in his hand to lynch some poor
unfortunate stranger, explains to the lone doubter that:

" Of course he will get a fair trail -

* THEN * we lynch him ..... "


Ben Duncan has been openly batting for the dark side of audio sanity for
decades - so he has zero credibility.

Phil Hanson and Red Sheep Communications was unknown to me so I looked up
his web site:

www.redsheep.co.uk

Looks a lot like a one man, advertising scam, agent for hire.

No surprises there.

Anyone know where the nooses are kept round here ???



..... Phil

Jim Lesurf wrote:

I got my latest copy of 'Stereophile' yesterday and started to read it. I
came across comments by Paul Messenger about some work that Russ Andrews
and Ben Duncan have recently put onto the web. This seems to be taken by
Paul Messenger as showing that Russ's claims re some of his products are
"now supported by proper scientific analysis".

But having looked at

http://www.russandrews.com/downloads...estPremRes.pdf

There appear to be two components to this, do the Russ Andrews mains lead
attenuate mains bourn noise and does mains bourn noise have any effect on
Hi-Fi systems.

It may have been demonstrated that the fancy cables can show some RF
attenuation but it is not demonstrated that this has any effect on sound
quality, that remains just a belief, "RFI is a major pollutant and we
believe that it is one of the major reasons why Hi-Fi systems do not perform
at their best".

This is hardly peer reviewed science. In my view it is just more Hi-Fi
magazine style guffology but I cannot prove that, it is just my belief based
on the evidence of my unreliable ears, also not peer reviewed.

Are either Paul Messenger or Ben Duncan trustworthy sources?


Enjoy,



--
David Pitt

On Sun, 21 Jun 2009 12:17:15 +0100, David Pitt
wrote:

Are either Paul Messenger or Ben Duncan trustworthy sources?

I believe it was Ben Duncan, years ago, who attempted to show that
speaker cables changed their delay characteristics with current. He
set up an experiment to demonstrate this, measuring frequency response
and delay with different currents - they did indeed change.
Unfortunately, the way he changed the current was by changing the load
on the end of the cable. It was of course this that changed the
measured delay - perfectly in line with established theory.

So no, Ben Duncan is not a reliable or trustworthy source.

d