The stones had come yesterday, when I went home there the package was. I
was in direct contact with the manufacturer and CEO of Shakti
Innovations, and told him what I intended to do with them, ultimately,
and he immediately agreed to send me an evaluation package.

The inventor of the shakti says that the "stone" is actually a nickname,
that it is moulden limestone powder and inside it there are three
patented "trap circuits" absorbing the EMI within components. Hmmm..

I applied a "stone" to each the CD player and the amp (put 'em on top,
smack in the middle). I applied a pair of on-lines on the speaker
terminals of the amp, one for each channel (they had this blue guey on
them that make them stick). I also applied a pair of on-lines on the rca
interconnects.

I sat down for a listen, my "reference" CD the BVSC with Ry Cooder..
Just then the wife comes along to the room asking me what those silly
looking stones are doing on top of the "stereo", as she tends to call my
system. As I am trying to explain and she is trying to keep her laughter
I notice something happening in the general direction of the "stereo"...

Here goes, this is what I heard: With the shakti there is more body,
definition, intensity, sincerity, clarity, more of everything that's
good _*across the board*_ !!!

It seems though, the shakti make the REAL difference with complex,
multi-sounds kind of instrumental music. _Everything_ is enhanced. The
soundstage is almost frighteningly darker in the huge, empty
background; sounds seem to come out of the big wide empty darkness
situated in the general direction of the speakers.

The bass gets more definition, exact borders as to where it starts and
ends. And the shakti also teach how to hear the essentials, in a way,
the complete music, they don't bring forth more detail, but teach you to
"notice" some *more* of the detail you actually heard but never
noticed before.

Well, I have decided that whatever I will do concerning the shakti in
the future, one thing is for sure; I will keep these evaluation units.

For whatever it is worth, IMHO, in an ideal world the shakti circuitry
would not be considered a "tweak" but an essential part of any system.

*I know* what the borg'll think, and write. Their prejudice is not open
for argument. But I am determined to not answer even the personal
insults coming my way after this. I felt that it is my *duty* to the
hobby and myself that I report something as significant as this, honestly.

My suggestion to all the "normals" out there would be that before
condemning me and starting to make jokes about kidney stones, tv dinners
of the ****borg, etc, that they actually give these things a try. I am
sure that no one in his right mind can't help but notice the very
significant difference this piece of equipment brings.

Fella wrote:


The stones had come yesterday,


Here's their official website: http://www.tricell-ent.com/Shakti.htm



Ok Fella, I'm still reading their website. I'll comment later.

JBorg wrote:

Fella wrote:


The stones had come yesterday,



Here's their official website: http://www.tricell-ent.com/Shakti.htm



Ok Fella, I'm still reading their website. I'll comment later.



I think this would be more beneficial reading:

http://www.shakti-innovations.com/questions.htm

"Fella" wrote in message



Here goes, this is what I heard: With the shakti there is more body,
definition, intensity, sincerity, clarity, more of everything that's
good _*across the board*_ !!!

Yawn. Yet another example of placebo effects.

Arny Krueger wrote:

"Fella" wrote in message




Here goes, this is what I heard: With the shakti there is more body,
definition, intensity, sincerity, clarity, more of everything that's
good _*across the board*_ !!!


Yawn. Yet another example of placebo effects.



Ok, since you were not personally insulting, or offensive, in a way, I
will answer this one. Here is why, in my *opinion* the effects could not
have been placebo: I could not have even *imagined* the changes that
actually happened to the sound. One puts the changes onto words, or
rather translates them, but they have to be experienced to find out what
they really are.

With placebo you take a sugar pill thinking it is aspirin and your
headache goes away, for example. You are anticipating that effect, so it
happens. But with this thing you wouldn't *dare* to anticipate such a
difference! It is that significant.

While I was opening the package I was thinking to myself that, damn, I
must be nuts. While I was trying to explaining the stuff to my grinning
wife I was anticipating embarrasment in front of her, as nothing would
happen. I had no idea, nor could I dare to anticipate what was to come.

The wife, btw, said briefly that the sound was "more like in waves" with
the shakti, as compared to it having "sharp edges" before. She thinks
that the high-end sound of my "stereo" is "pompous". She does sometimes
accept the beauty of it all, but she thinks the whole hobby is not worth
it, it wouldn't matter if the same sounds came out of the TV set, it
would still be music. So being so much *out* of the picture even she
noticed the difference.

"Fella" wrote in message

Arny Krueger wrote:

"Fella" wrote in message


Here goes, this is what I heard: With the shakti there is more body,
definition, intensity, sincerity, clarity, more of everything that's
good _*across the board*_ !!!

Yawn. Yet another example of placebo effects.

Ok, since you were not personally insulting, or offensive, in a way, I
will answer this one. Here is why, in my *opinion* the effects could
not have been placebo: I could not have even *imagined* the changes
that actually happened to the sound.

Yawn again. Anybody who thinks that they could not imagine something
obviously has a rather high estimate of their infallibity and a low estimate
of their creativity.

One puts the changes onto words,
or rather translates them, but they have to be experienced to find
out what they really are.

The idea that there has to be a certain well-defined stimulus in order for
there to be a given perception presumes that there are no such things as
illusions and perceptual errors. There are therefore no mirages. There is no
such thing as pilot's vertigo. A young man named Kennedy didn't fly his
plane into the ocean because he misperceived where he could fly his plane.

With placebo you take a sugar pill thinking it is aspirin and your
headache goes away, for example. You are anticipating that effect, so
it happens. But with this thing you wouldn't *dare* to anticipate
such a difference! It is that significant.

That would be a very narrow view of placebo effects. A well-known example of
the more general kind of placebo effect is familiar to just about everybody
with any serious experience with audio production. Let me breifly explain a
typical mixing console. A typical mixng console has upwards of 200 knobs
and controls. Some percentage of them which can affect sound quality at any
particular time. Just about everybody who has used a mixing console has made
some change that they thought made a change or improvement, only to later
find out that the knob they turned was right next to the knob that would
have the effect they desired. The knob they did turn turned did nothing to
the sound at all. But, they perceived the change, anyhow.

While I was opening the package I was thinking to myself that, damn, I
must be nuts.

Hold that thought!

While I was trying to explaining the stuff to my
grinning wife I was anticipating embarrasment in front of her, as
nothing would happen. I had no idea, nor could I dare to anticipate
what was to come.

I don't know where people get the idea that there are fixed and predictable
cause-and-effect relationships with illusions.

Arny Krueger wrote:

While I was opening the package I was thinking to myself that, damn, I
must be nuts.


Hold that thought!


Watch it.

On Thu, 10 Feb 2005 07:57:07 -0500, "Arny Krueger"
wrote:


While I was trying to explaining the stuff to my
grinning wife I was anticipating embarrasment in front of her, as
nothing would happen. I had no idea, nor could I dare to anticipate
what was to come.

I don't know where people get the idea that there are fixed and predictable
cause-and-effect relationships with illusions.

Why don't you admit that hi-fi reproduction is an "illusion" in the
first place?

George M. Middius wrote:

the correct (human) term for the idea Krooger is trying to
articulate is "expectation effect".


Agreed. Seems quite futile though, to talk about ones opinions and
observations about audio in an *opinion* forum. As some people seem to
get sincerely offended.

"Fella" wrote in message


I think this would be more beneficial reading:

http://www.shakti-innovations.com/questions.htm

This would be a more beneficial experience: www.pcabx.com .

The PCABX web site provides listeners with the opportunity to make sonic
judgments based on just sound quality. PCABX test listening conditions
are optimized as much as possible, in order to facilitate sensitive results.
PCABX tests can address theoretical questions such as "What does THD sound
like, and how much can I hear", or comparisons of the sound quality of
various pieces of equipment.

Until PCABX very few audiophiles had the opportunity to compare audio
products based on just sound quality, with so many relevant parameters and
conditions held constant and optimized. Therefore, many so-called sonic
judgments have no doubt been made based on non-sonic as well as random sonic
factors that are irrelevant to a product's basic inherent sound quality.
These factors include appearance, level matching, and the timing of musical
passages being listened to.

Some of these non-sonic factors such as appearance do relate to how products
rate in the mind of a typical consumer. However, most consumers agree that
sound quality is the most important thing and should be considered first.
While most consumers want good-looking equipment, product appearance is
generally good enough that a wide variety products are acceptable if their
sound quality is top-rate.

Other factors such as level matching and timing of musical passages being
listened to are so completely uncontrolled in most home and stereo shop
listening tests as to constitute a clear and irrelevant confusing variable.
PCABX provides a means for important factors like level matching and timing
of musical passages to be held precisely constant.

Another important factor in listening tests is listener training. Casual
listening is generally not the best way to hear small differences. However,
it is well known that subtle differences can build up in the listener's mind
over a period of time and lead to stress, displeasure and listener fatigue.
PCABX provides several means by which even a naive listener can be educated
to listen reliably for subtle differences.

"George M. Middius" wrote in message


"Fella" wrote in message


With placebo you take a sugar pill thinking it is aspirin and your
headache goes away, for example. You are anticipating that effect, so it
happens. But with this thing you wouldn't *dare* to anticipate such a
difference! It is that significant.

Note that this paragraph relates placeboes to anticipation or expectation.
Exactly the word placebo is used at the beginning of the paragraph and by
the end of the paragraph the word anticipation is used to explain it.


In passing, I'd add that the term "placebo effect"
is out of place in subjective audio evaluations.

And Middius' qualitifications for making this far-reaching pronouncement is?

Middius has the following relevant education: none known

Middius has the following relevant experience: none known

As you almost stated
in your response, the correct (human) term for the idea Krooger is
trying to articulate is "expectation effect".

In essence Middius is claiming that expectation effects are irrelevant to
anticipations or placebos, while Fella uses an anticipation to explain a
placebo effect.

Well, once these two *experts* settle their semantic differences, I'll
address whatever wisdom if any, that results.

On Thu, 10 Feb 2005 08:54:51 -0500, "Arny Krueger"
wrote:

"Fella" wrote in message


I think this would be more beneficial reading:

http://www.shakti-innovations.com/questions.htm

This would be a more beneficial experience: www.pcabx.com .

The PCABX web site provides listeners with the opportunity to make sonic
judgments based on just sound quality. PCABX test listening conditions
are optimized as much as possible, in order to facilitate sensitive results.
PCABX tests can address theoretical questions such as "What does THD sound
like, and how much can I hear", or comparisons of the sound quality of
various pieces of equipment.

Until PCABX very few audiophiles had the opportunity to compare audio
products based on just sound quality, with so many relevant parameters and
conditions held constant and optimized. Therefore, many so-called sonic
judgments have no doubt been made based on non-sonic as well as random sonic
factors that are irrelevant to a product's basic inherent sound quality.
These factors include appearance, level matching, and the timing of musical
passages being listened to.

Some of these non-sonic factors such as appearance do relate to how products
rate in the mind of a typical consumer. However, most consumers agree that
sound quality is the most important thing and should be considered first.
While most consumers want good-looking equipment, product appearance is
generally good enough that a wide variety products are acceptable if their
sound quality is top-rate.

Other factors such as level matching and timing of musical passages being
listened to are so completely uncontrolled in most home and stereo shop
listening tests as to constitute a clear and irrelevant confusing variable.
PCABX provides a means for important factors like level matching and timing
of musical passages to be held precisely constant.

Another important factor in listening tests is listener training. Casual
listening is generally not the best way to hear small differences. However,
it is well known that subtle differences can build up in the listener's mind
over a period of time and lead to stress, displeasure and listener fatigue.
PCABX provides several means by which even a naive listener can be educated
to listen reliably for subtle differences.

How would PCABX be of any help in evaluating Shakti Stones?

"Fella" wrote in message
...

The stones had come yesterday, when I went home there the package was. I
was in direct contact with the manufacturer and CEO of Shakti Innovations,
and told him what I intended to do with them, ultimately, and he
immediately agreed to send me an evaluation package.

The inventor of the shakti says that the "stone" is actually a nickname,
that it is moulden limestone powder and inside it there are three patented
"trap circuits" absorbing the EMI within components. Hmmm..

I applied a "stone" to each the CD player and the amp (put 'em on top,
smack in the middle). I applied a pair of on-lines on the speaker
terminals of the amp, one for each channel (they had this blue guey on
them that make them stick). I also applied a pair of on-lines on the rca
interconnects.

I sat down for a listen, my "reference" CD the BVSC with Ry Cooder..
Just then the wife comes along to the room asking me what those silly
looking stones are doing on top of the "stereo", as she tends to call my
system. As I am trying to explain and she is trying to keep her laughter I
notice something happening in the general direction of the "stereo"...

Here goes, this is what I heard: With the shakti there is more body,
definition, intensity, sincerity, clarity, more of everything that's good
_*across the board*_ !!!

It seems though, the shakti make the REAL difference with complex,
multi-sounds kind of instrumental music. _Everything_ is enhanced. The
soundstage is almost frighteningly darker in the huge, empty background;
sounds seem to come out of the big wide empty darkness situated in the
general direction of the speakers.

The bass gets more definition, exact borders as to where it starts and
ends. And the shakti also teach how to hear the essentials, in a way, the
complete music, they don't bring forth more detail, but teach you to
"notice" some *more* of the detail you actually heard but never noticed
before.

Well, I have decided that whatever I will do concerning the shakti in the
future, one thing is for sure; I will keep these evaluation units.

For whatever it is worth, IMHO, in an ideal world the shakti circuitry
would not be considered a "tweak" but an essential part of any system.

*I know* what the borg'll think, and write. Their prejudice is not open
for argument. But I am determined to not answer even the personal insults
coming my way after this. I felt that it is my *duty* to the hobby and
myself that I report something as significant as this, honestly.

My suggestion to all the "normals" out there would be that before
condemning me and starting to make jokes about kidney stones, tv dinners
of the ****borg, etc, that they actually give these things a try. I am
sure that no one in his right mind can't help but notice the very
significant difference this piece of equipment brings.

Interesting. I'm happy it worked for you. Two points on the Shakti stuff
based on first hand experience:

1. I tried the evaluation package myself with two systems. Avantgarde
horns/Nagra tubes/Sony SACD and Martin-
logan stats/Parasound Halo/Blowtorch/Denon "all-format" player. No
difference. None whatsoever. Nada. Perhaps it was the MIT cabling in the SS
system that had already rectified the inherent flaws in the John Curl
designed electronics and compensated for the construction shortcuts taken in
the $18K Blowtorch preamp. But what explains the lack of results with the
tubed system? The perfection of swiss design? The superiority of tubed
amplification? I dunno....

2. A handy audiophile friend of mine made visually accurate copies of the
Shakti stones from solid soapstone a couple of years back. Against all odds,
they worked seemingly just as well as the real deal. He made enough money
from them to start a business not related to audio and he is doing well
today. And he never received a single complaint from a customer related to
the performance of the product. But they did not work in my system either. I
guess I'm just SOL.

Cheers,

Margaret
-thawing and typing-

"Fella" wrote in message
...
Arny Krueger wrote:

While I was opening the package I was thinking to myself that, damn, I
must be nuts.


Hold that thought!


Watch it.

One question. Since the only EMI that is shown being absorbed or blocked by
the Stones is in the frequency range of 50 mHz - GHz, well out the range of
human hearing, how do you explain any audible effect?

"George M. Middius" wrote in message
...


Margaret von B. said:

2. A handy audiophile friend of mine made visually accurate copies of the
Shakti stones from solid soapstone a couple of years back. Against all
odds,
they worked seemingly just as well as the real deal. He made enough money
from them to start a business not related to audio and he is doing well
today.

Soapstone is a pretty material for ornaments, you will note. Completely
the
opposite of any 'borg-approved electronics.



Actually I have a wood-burning range/pizza oven/fireplace combination made
of soapstone. Very beautiful and functional between the kitchen and the
"great room".

Cheers,

Margaret

"Michael McKelvy" said:

One question. Since the only EMI that is shown being absorbed or blocked by
the Stones is in the frequency range of 50 mHz - GHz, well out the range of
human hearing, how do you explain any audible effect?


Even frequencies that high can cause problems with unsufficently
shielded and non-EMC compliant amplifiers.

Which still is common practice in high end.
Simplicity in design has its pros and cons, you will note.

Note also that most tube amps don't suffer from said effects because
of their inherent low pass filters, hence even if Shakti stones work
as described on their website, they won't do very much for tubed
systems IMO (from a technical POV that is!).

--
Sander de Waal
" SOA of a KT88? Sufficient. "

"Sander deWaal" wrote in message
...
"Michael McKelvy" said:

One question. Since the only EMI that is shown being absorbed or blocked
by
the Stones is in the frequency range of 50 mHz - GHz, well out the range
of
human hearing, how do you explain any audible effect?


Even frequencies that high can cause problems with unsufficently
shielded and non-EMC compliant amplifiers.


And wouldn't a proper fix for theat be considerably cheaper that the stones?

Allow me to remain skeptical until proper DBT's are conducted.


Which still is common practice in high end.
Simplicity in design has its pros and cons, you will note.

Note also that most tube amps don't suffer from said effects because
of their inherent low pass filters, hence even if Shakti stones work
as described on their website, they won't do very much for tubed
systems IMO (from a technical POV that is!).

--
Sander de Waal
" SOA of a KT88? Sufficient. "

"Michael McKelvy" said:

One question. Since the only EMI that is shown being absorbed or blocked
by
the Stones is in the frequency range of 50 mHz - GHz, well out the range
of
human hearing, how do you explain any audible effect?

Even frequencies that high can cause problems with unsufficently
shielded and non-EMC compliant amplifiers.

And wouldn't a proper fix for theat be considerably cheaper that the stones?


Of course.
But my take on this is: as long as it isn't necessary to take strong
measures against RFI in a circuit design, don't do it.
It can definitely ruin the sound IMO.


Allow me to remain skeptical until proper DBT's are conducted.


Ego te absolvo, my son ;-)

PS I'm sceptical as well, but I don't deny that they might work on
another than just a technical level.
If they work as advertised, that is as an RF absorber, this could be
easily measured I assume?
Whether I'd pay $1200 or whatever the Shaktis cost, is an entirely
different matter. RFI supression is definitely a cheaper option.

However, Fella seems to be happy with them.
How would one conduct a DBT with/without Shaktis BTW?

I'm still awaiting his DBT results for the powercords.

--
Sander de Waal
" SOA of a KT88? Sufficient. "

"Sander deWaal" wrote in message

"Michael McKelvy" said:

One question. Since the only EMI that is shown being absorbed or
blocked by the Stones is in the frequency range of 50 mHz - GHz,
well out the range of human hearing, how do you explain any audible
effect?

Even frequencies that high can cause problems with unsufficently
shielded and non-EMC compliant amplifiers.

I'm willing to allow that a suffiently poorly-designed amplifier might be
interfered with by RF interferance. However, there's no evidence that the
Shatki devices would address these problems. There's even evidence that they
are incompetently designed if this is their purpose.

Given that properly-designed external RFI filters are commodity items
selling for a few dollars, why would someone want to spend far more to get
far less?

Which still is common practice in high end.

Seems like a great reason to avoid high end amplfiiers since they are so
likely to be incompetently designed.

Simplicity in design has its pros and cons, you will note.

Note also that most tube amps don't suffer from said effects because
of their inherent low pass filters,

OTOH, tubed amps are more prone to EMI problems due to unique tube-only
problems like grid rectification, Miller capacitance and their high input
impedances. I hard a lot more RFI problems during the days of tubes than I
do now.

BTW, SS amplifiers are also inherently low pass filters.

hence even if Shakti stones work
as described on their website, they won't do very much for tubed
systems IMO (from a technical POV that is!).

From a Sander technical view, that is. ;-)

"Arny Krueger" said:

Note also that most tube amps don't suffer from said effects because
of their inherent low pass filters,

OTOH, tubed amps are more prone to EMI problems due to unique tube-only
problems like grid rectification, Miller capacitance and their high input
impedances. I hard a lot more RFI problems during the days of tubes than I
do now.


Grid rectification: the voltage span of an average power amp input
tube is about 2 volts.
The voltage span of an average base-emitter junction is what...20 mV?

Miller capacitance: dependent on circuitry.
*Every* amplifying device with inverting output suffers from mr.
Miller.
Examples of said circuits would be CCC, CEC, CSC.

High input impedance: dependent on circuitry.
A tube amp with a 10 k resistor at the grid to ground won't be more
susceptible (sp?) to RFI than an average bipolar input.
Let alone FETs or MOSFETs.
What was the first transistor again in your FM-frontend, Arny? ;-)

Granted that most tube amps have higher value input resistors.


BTW, SS amplifiers are also inherently low pass filters.


In general, SS circuitry is capable of handling higher frequencies
than tube equipment, consider an average output transformer with a
corner freq. at 50 kHz or so.

Of course, a good practice is to add an anti-slewing filter at the
input of the amp (even with tubes this might be beneficial!), but some
designers select a corner frequency of 150 or 200 kHz.
Besides, that is mostly a simple RC 6 dB.oct filter, not steep enough
to supress real strong RF energy.


hence even if Shakti stones work
as described on their website, they won't do very much for tubed
systems IMO (from a technical POV that is!).

From a Sander technical view, that is. ;-)


Gratuitous personal insult ignored.

--
Sander de Waal
" SOA of a KT88? Sufficient. "

"Sander deWaal" wrote in message

"Arny Krueger" said:

Note also that most tube amps don't suffer from said effects because
of their inherent low pass filters,

OTOH, tubed amps are more prone to EMI problems due to unique
tube-only problems like grid rectification, Miller capacitance and
their high input impedances. I hard a lot more RFI problems during
the days of tubes than I do now.


Grid rectification: the voltage span of an average power amp input
tube is about 2 volts.

A serious problem because of the high impedances involved and the fact that
tubes are frequently run without local feedback.

The voltage span of an average base-emitter junction is what...20 mV?

Irrelevant because transistor inputs stages are always far lower than with
tubes and almost always run with emitter degeneration.


Miller capacitance: dependent on circuitry.

Also dependent on the tubes themselves.

*Every* amplifying device with inverting output suffers from mr.
Miller.

It's all in the quantification, and the quantities are vastly differnt for
tubes and SS.

Examples of said circuits would be CCC, CEC, CSC.

High input impedance: dependent on circuitry.

Of course, but as a matter of course tubed circuts have far higher input
impedances.

A tube amp with a 10 k resistor at the grid to ground won't be more
susceptible (sp?) to RFI than an average bipolar input.

Perhaps, but irrelevant due to the common practice of using far higher grid
resistors than 10K.

Let alone FETs or MOSFETs.

Oh my goodness, it's a red herring. Actually two of them.

What was the first transistor again in your FM-frontend, Arny? ;-)

Yet another red herring. BTW, the cross-modulation characteristics of SS FM
front ends are generally better than what we had when tubes were king.

Granted that most tube amps have higher value input resistors.

Thanks for agreeing that your argument based on unrealistically low grid
resistors was irrelevant, Sander.

BTW, SS amplifiers are also inherently low pass filters.

In general, SS circuitry is capable of handling higher frequencies
than tube equipment, consider an average output transformer with a
corner freq. at 50 kHz or so.

Actually 50 KHz or so is not an uncommon corner frequency for SS amps.

Of course, a good practice is to add an anti-slewing filter at the
input of the amp (even with tubes this might be beneficial!), but some
designers select a corner frequency of 150 or 200 kHz.

Slewing was a problem in someone's mind by the time it was publicized.

Besides, that is mostly a simple RC 6 dB.oct filter, not steep enough
to supress real strong RF energy.

A 6 dB/oct filter cornering at 50 KHz is down over 20 dB at 500 KHz, 40 dB
at 5 MHz and 60 dB down at the 50 MHz that Mike origionally mentioned.

hence even if Shakti stones work
as described on their website, they won't do very much for tubed
systems IMO (from a technical POV that is!).

From a Sander technical view, that is. ;-)

Gratuitous personal insult ignored.

Inability to gracefully perceive a gentle stab due to a technological
disagreement noted.

"Arny Krueger" wrote in message
...

:
: The voltage span of an average base-emitter junction is what...20 mV?
:
: Irrelevant because transistor inputs stages are always far lower than with
: tubes and almost always run with emitter degeneration.

--Sorry, my device comes up 'hands in the air'. What language is *that *?

:
: Miller capacitance: dependent on circuitry.
:
: Also dependent on the tubes themselves.
:
: *Every* amplifying device with inverting output suffers from mr.
: Miller.
:
: It's all in the quantification, and the quantities are vastly differnt for
: tubes and SS.
:

--Sorry, my device comes up 'hands in the air'. What language is *that *?

: Examples of said circuits would be CCC, CEC, CSC.
:
: High input impedance: dependent on circuitry.
:
: Inability to gracefully perceive a gentle stab due to a technological
: disagreement noted.
:
Inability to produce coherent topic discussion noted;-)
Rudy

"Arny Krueger" wrote in message
...
..
PCABX provides several means by which even a naive listener can be
brainwashed
to fail in recognizing profound differences.






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On Thu, 10 Feb 2005 17:01:08 -0500, "Arny Krueger"
wrote:

Inability to gracefully perceive a gentle stab due to a technological
disagreement noted.

Yep, this debate is going to be a hot. Is the webcast going to be
video? Because, if the graphics of his website is any indication, the
Powerpoint presentation should be laughable as well...

On Fri, 11 Feb 2005 01:07:51 -0600, in rec.audio.opinion you wrote:

On Thu, 10 Feb 2005 17:01:08 -0500, "Arny Krueger"
wrote:

Inability to gracefully perceive a gentle stab due to a technological
disagreement noted.

Yep, this debate is going to be a hot.

Or a hoot, even.

Fella" wrote
George M. Middius wrote:


the correct (human) term for the idea Krooger is trying to
articulate is "expectation effect".


Agreed. Seems quite futile though, to talk about ones opinions and
observations about audio in an *opinion* forum. As some people seem to get
sincerely offended.



Like this coward below. I wonder country he came from.




********
Have you considered seeking professional help?
Your condition is rapidly deteriorating, troll.

FU2
*******

Fella" wrote
George M. Middius wrote:


the correct (human) term for the idea Krooger is trying to
articulate is "expectation effect".


Agreed. Seems quite futile though, to talk about ones opinions and
observations about audio in an *opinion* forum. As some people seem to get
sincerely offended.



Like this coward below. I wonder what *country* he came from.




********
Have you considered seeking professional help?
Your condition is rapidly deteriorating, troll.

FU2
*******

JBorg a écrit :

I wonder country he came from.


I wonder how a guy with such *caricatural* bias can show the
minimum objectivity to report anything interesting
concerning an audio system...

;-)

Lionel wrote
JBorg a écrit :


I wonder country he came from.


I wonder how a guy with such *caricatural* bias can show the minimum
objectivity to report anything interesting concerning an audio system...

;-)


Hi Lionel, I hope he take his shield off and reply to this...

---

François Yves Le Gal wrote:
Fella wrote:

Hello.



I felt that it is my *duty* to the
hobby and myself that I report something as significant as this, honestly.

Have you considered seeking professional help?

He felt it neccessary to share something that greatly improve
the sound of his stereo system. I wonder what the diagnosis be
for such offensive act.


Your condition is rapidly deteriorating, troll.

He stated on several occasion that he plan to share his experience
with this device soon after he had a chance listening with them in his
system. I don't think he intend this as a troll.

Sander deWaal wrote





I'm still awaiting his DBT results for the powercords.


He done the pwr cord test, and he end up not liking the upgraded
cord from AQ.

Fella" wrote




My suggestion to all the "normals" out there would be that before condemning
me and starting to make jokes about kidney stones, tv dinners of the
****borg, etc, that they actually give these things a try. I am sure that no
one in his right mind can't help but notice the very significant difference
this piece of equipment brings.



Fella, I'm glad to know that the Stone is working out effectively
on your stereo system. I'm also glad that you're very happy with
the result, and that you gonna enjoy listening to music even more.

Don't let *******s like Arnii Krooger put you down.

"JBorg" said:

I'm still awaiting his DBT results for the powercords.

He done the pwr cord test, and he end up not liking the upgraded
cord from AQ.


Thanks, I guess I missed that.

--
Sander de Waal
" SOA of a KT88? Sufficient. "

"Arny Krueger" said:

OTOH, tubed amps are more prone to EMI problems due to unique
tube-only problems like grid rectification, Miller capacitance and
their high input impedances. I hard a lot more RFI problems during
the days of tubes than I do now.

Grid rectification: the voltage span of an average power amp input
tube is about 2 volts.

A serious problem because of the high impedances involved and the fact that
tubes are frequently run without local feedback.


A cathode resistor isn't local feedback?
You're not thinking of auto-grid bias, are you?
A method that isn't used anymore in "modern" tube amps, at least not
that I know of.

This might also explain why you think tube inputs have such extremely
high input resistors, 10 megohm wasn't unusual is such an arrangement.


The voltage span of an average base-emitter junction is what...20 mV?

Irrelevant because transistor inputs stages are always far lower than with
tubes and almost always run with emitter degeneration.


Partly agreed, see above for the same rule that applies to cathode
resistors.
Look up "Ebers-Moll" for a better understanding about driving bipolar
transistors.


Miller capacitance: dependent on circuitry.

Also dependent on the tubes themselves.


Also agreed, but certainly not just "due to unique tube problems like
Miller capacitance [.....] ".


*Every* amplifying device with inverting output suffers from mr.
Miller.


It's all in the quantification, and the quantities are vastly differnt for
tubes and SS.


Also agreed, but certainly not just "due to unique tube problems like
Miller capacitance [.....] ".


Examples of said circuits would be CCC, CEC, CSC.

High input impedance: dependent on circuitry.

Of course, but as a matter of course tubed circuts have far higher input
impedances.


Which is compensated for by the much karger grid voltage span.


A tube amp with a 10 k resistor at the grid to ground won't be more
susceptible (sp?) to RFI than an average bipolar input.

Perhaps, but irrelevant due to the common practice of using far higher grid
resistors than 10K.


They're 25 kohms in my tube amps.

Not that I'm alone in this, you will note.


Let alone FETs or MOSFETs.

Oh my goodness, it's a red herring. Actually two of them.


Actually, no.
One of the main *advantages* of (MOS)FETs is their voltage-driven
nature.


What was the first transistor again in your FM-frontend, Arny? ;-)

Yet another red herring. BTW, the cross-modulation characteristics of SS FM
front ends are generally better than what we had when tubes were king.


Only due to clamping diodes.
If the same technique is used with a triode- or even penthode input
circuits (NOT hexodes or pentagrid tubes!), cross-modulation is almost
not an item to worry about.
Noise may be, though.


Granted that most tube amps have higher value input resistors.

Thanks for agreeing that your argument based on unrealistically low grid
resistors was irrelevant, Sander.


Not unrealistic at all considering my design views, but then again,
*I* am able to put off my blinders ;-)


BTW, SS amplifiers are also inherently low pass filters.

In general, SS circuitry is capable of handling higher frequencies
than tube equipment, consider an average output transformer with a
corner freq. at 50 kHz or so.

Actually 50 KHz or so is not an uncommon corner frequency for SS amps.


Due to what property, exactly?


Of course, a good practice is to add an anti-slewing filter at the
input of the amp (even with tubes this might be beneficial!), but some
designers select a corner frequency of 150 or 200 kHz.

Slewing was a problem in someone's mind by the time it was publicized.


Since Otala, Garde et al, we know better ;-)


Besides, that is mostly a simple RC 6 dB.oct filter, not steep enough
to supress real strong RF energy.

A 6 dB/oct filter cornering at 50 KHz is down over 20 dB at 500 KHz, 40 dB
at 5 MHz and 60 dB down at the 50 MHz that Mike origionally mentioned.


One wrong grounding point may wreak havoc with that 60 dB number.


hence even if Shakti stones work
as described on their website, they won't do very much for tubed
systems IMO (from a technical POV that is!).

From a Sander technical view, that is. ;-)

Gratuitous personal insult ignored.

Inability to gracefully perceive a gentle stab due to a technological
disagreement noted.


Please stop being so hostile! ;-)

--
Sander de Waal
" SOA of a KT88? Sufficient. "

"Sander deWaal" wrote in message

"Arny Krueger" said:

OTOH, tubed amps are more prone to EMI problems due to unique
tube-only problems like grid rectification, Miller capacitance and
their high input impedances. I hard a lot more RFI problems during
the days of tubes than I do now.

Grid rectification: the voltage span of an average power amp input
tube is about 2 volts.

A serious problem because of the high impedances involved and the
fact that tubes are frequently run without local feedback.

A cathode resistor isn't local feedback?

Not if its bypasssed.

You're not thinking of auto-grid bias, are you?

No.

A method that isn't used anymore in "modern" tube amps, at least not
that I know of.

Agreed.

This might also explain why you think tube inputs have such extremely
high input resistors, 10 megohm wasn't unusual is such an arrangement.

470K still is common. that's about 50 times the last number you mentioned,
Sander. Hunt around, sooner or later you'll find a believable number.

The voltage span of an average base-emitter junction is what...20
mV?

Irrelevant because transistor inputs stages are always far lower
than with tubes and almost always run with emitter degeneration.

Partly agreed, see above for the same rule that applies to cathode
resistors.

Look up "Ebers-Moll" for a better understanding about driving bipolar
transistors.

Here we go, the big tube eggshpert is now talking down his nose at me.

Miller capacitance: dependent on circuitry.

Also dependent on the tubes themselves.

Also agreed, but certainly not just "due to unique tube problems like
Miller capacitance [.....] ".

Fess up Sander, Miller capacitance is a far more significant issue with
tubes.

*Every* amplifying device with inverting output suffers from mr.
Miller.

It's all in the quantification, and the quantities are vastly
differnt for tubes and SS.

Also agreed, but certainly not just "due to unique tube problems like
Miller capacitance [.....] ".

Yawn.

Examples of said circuits would be CCC, CEC, CSC.

High input impedance: dependent on circuitry.

Of course, but as a matter of course tubed circuts have far higher
input impedances.

Which is compensated for by the much karger grid voltage span.

Nope.

A tube amp with a 10 k resistor at the grid to ground won't be more
susceptible (sp?) to RFI than an average bipolar input.

Perhaps, but irrelevant due to the common practice of using far
higher grid resistors than 10K.

They're 25 kohms in my tube amps.

That's a choice you get to make. But, it says nothing about tubed amps in
general.

Not that I'm alone in this, you will note.

Not that you set the rule or the average, either.

Let alone FETs or MOSFETs.

Oh my goodness, it's a red herring. Actually two of them.

Actually, no.

Yawn.

One of the main *advantages* of (MOS)FETs is their voltage-driven
nature.

What was the first transistor again in your FM-frontend, Arny? ;-)

Yet another red herring. BTW, the cross-modulation characteristics
of SS FM front ends are generally better than what we had when tubes
were king.

Only due to clamping diodes.

Nope. Cross modulation is about nonlinear distortion, and clamping diodes
increase that, not decrease it.

If the same technique is used with a triode- or even penthode input
circuits (NOT hexodes or pentagrid tubes!), cross-modulation is almost
not an item to worry about.

See previous comment.

Noise may be, though.

Granted that most tube amps have higher value input resistors.

Thanks for agreeing that your argument based on unrealistically low
grid resistors was irrelevant, Sander.

Not unrealistic at all considering my design views, but then again,
*I* am able to put off my blinders ;-)

What blinders? The vacuum tube horse has been dead in the mainstream of hi
fi for about 30 years. Putting blinders on a dead horse makes very little
sense.

BTW, SS amplifiers are also inherently low pass filters.

In general, SS circuitry is capable of handling higher frequencies
than tube equipment, consider an average output transformer with a
corner freq. at 50 kHz or so.

Actually 50 KHz or so is not an uncommon corner frequency for SS
amps.

Due to what property, exactly?

Desire to have an amp that is nice to work with.


Of course, a good practice is to add an anti-slewing filter at the
input of the amp (even with tubes this might be beneficial!), but
some designers select a corner frequency of 150 or 200 kHz.

Slewing was a problem in someone's mind by the time it was
publicized.

Since Otala, Garde et al, we know better ;-)

Yes, Otala is known to have been an alarmist, to say the least.

Besides, that is mostly a simple RC 6 dB.oct filter, not steep
enough to supress real strong RF energy.

A 6 dB/oct filter cornering at 50 KHz is down over 20 dB at 500 KHz,
40 dB at 5 MHz and 60 dB down at the 50 MHz that Mike origionally
mentioned.

One wrong grounding point may wreak havoc with that 60 dB number.

How many red herrings does this make?

hence even if Shakti stones work
as described on their website, they won't do very much for tubed
systems IMO (from a technical POV that is!).

From a Sander technical view, that is. ;-)

Gratuitous personal insult ignored.

Inability to gracefully perceive a gentle stab due to a
technological disagreement noted.

Please stop being so hostile! ;-)

Yawn.

"Arny Krueger" said:

A serious problem because of the high impedances involved and the
fact that tubes are frequently run without local feedback.

A cathode resistor isn't local feedback?

Not if its bypasssed.


Ah. Another design tirck from me.
I rarely bypass cathode resistors.
My, I must be an exceptional tube amp designer ;-)


470K still is common. that's about 50 times the last number you mentioned,
Sander. Hunt around, sooner or later you'll find a believable number.


In older tube amps, such high input resistors were indeed common.
Modern tube amps, as far as i've seen them, use lower values from
10k....100 k.


Look up "Ebers-Moll" for a better understanding about driving bipolar
transistors.

Here we go, the big tube eggshpert is now talking down his nose at me.


Please find a quote by me where I pretend to be an expert (or
eggsphert) in *anything* , except tinkering.

Furthermore, the Ebers-Moll approach starts with the premise that
bipolars are voltage-driven.

But you knew this, right? ;-)


Also agreed, but certainly not just "due to unique tube problems like
Miller capacitance [.....] ".

Fess up Sander, Miller capacitance is a far more significant issue with
tubes.


I replied to your statement that those problems are "unique with
tubes, like Miller capacity etc".

Fess up Arnold, Miller capacitance is apparent in *every*
signal-inverting amplifying device.


High input impedance: dependent on circuitry.

Of course, but as a matter of course tubed circuts have far higher
input impedances.

Which is compensated for by the much karger grid voltage span.

Nope.


Yep.


Yet another red herring. BTW, the cross-modulation characteristics
of SS FM front ends are generally better than what we had when tubes
were king.

Only due to clamping diodes.

Nope. Cross modulation is about nonlinear distortion, and clamping diodes
increase that, not decrease it.


Remind me again when MOSFETs without internal clamping diodes are
available to designers.

Non-linear distortion, again due to the smaller BE voltage span as
compared to the larger GC span of a triode or penthode.


Granted that most tube amps have higher value input resistors.

Thanks for agreeing that your argument based on unrealistically low
grid resistors was irrelevant, Sander.

Not unrealistic at all considering my design views, but then again,
*I* am able to put off my blinders ;-)

What blinders? The vacuum tube horse has been dead in the mainstream of hi
fi for about 30 years. Putting blinders on a dead horse makes very little
sense.


Thanks anyway for discussing obsolete technology with me Arnold. ;-)


Actually 50 KHz or so is not an uncommon corner frequency for SS
amps.

Due to what property, exactly?

Desire to have an amp that is nice to work with.


I meant what causes the LPF character of an average SS amp?
In what stages is that most apparent?


Slewing was a problem in someone's mind by the time it was
publicized.

Since Otala, Garde et al, we know better ;-)

Yes, Otala is known to have been an alarmist, to say the least.


Otala was an optimist ;-)


Besides, that is mostly a simple RC 6 dB.oct filter, not steep
enough to supress real strong RF energy.

A 6 dB/oct filter cornering at 50 KHz is down over 20 dB at 500 KHz,
40 dB at 5 MHz and 60 dB down at the 50 MHz that Mike origionally
mentioned.

One wrong grounding point may wreak havoc with that 60 dB number.

How many red herrings does this make?


What was the minimum requirement for measuring S/N again?
When I once mentioned I couldn't measure better than -80 dB at one
time, you had a good laugh.

Think about a bipolar differential input, CMRR, and the actual signal
voltage needed to excurse it.

You may use Google, if you like ;-)

--
Sander de Waal
" SOA of a KT88? Sufficient. "

"Sander deWaal" wrote in message

"Arny Krueger" said:

A serious problem because of the high impedances involved and the
fact that tubes are frequently run without local feedback.

A cathode resistor isn't local feedback?

Not if its bypasssed.

Ah. Another design tirck from me.
I rarely bypass cathode resistors.

Good.

My, I must be an exceptional tube amp designer ;-)

Yawn.

470K still is common. that's about 50 times the last number you
mentioned, Sander. Hunt around, sooner or later you'll find a
believable number.

In older tube amps, such high input resistors were indeed common.
Modern tube amps, as far as i've seen them, use lower values from
10k....100 k.

100K being only 10 times higher than the number you previously mentioned...


First site I found with the search string tube preamp schematics:

http://www3.telus.net/public/vintage1/mu.jpg

1 meg grid resistor, bypassed cathode resistor

http://www3.telus.net/public/vintage1/phones.jpg

1 meg grid resistor, bypassed cathode resistor

http://www.triodeel.com/a340a.gif

220k grid resistor, bypassed cathode resistor

http://www.drtube.com/schematics/an/ankoru.gif

bypassed cathode resistor

http://www.drtube.com/schematics/ar/d40.gif

475 k grid resistor

http://www.drtube.com/schematics/ar/vt100.gif

100 K grid resistor

etc., etc.

Look up "Ebers-Moll" for a better understanding about driving
bipolar transistors.

Here we go, the big tube eggshpert is now talking down his nose at
me.

Please find a quote by me where I pretend to be an expert (or
eggsphert) in *anything* , except tinkering.

Sander wrote: " My, I must be an exceptional tube amp designer"

Furthermore, the Ebers-Moll approach starts with the premise that
bipolars are voltage-driven.

But you knew this, right? ;-)

Yawn.

Also agreed, but certainly not just "due to unique tube problems
like Miller capacitance [.....] ".

Fess up Sander, Miller capacitance is a far more significant issue
with tubes.

I replied to your statement that those problems are "unique with
tubes, like Miller capacity etc".

Fess up Arnold, Miller capacitance is apparent in *every*
signal-inverting amplifying device.

Can apparent be a synonum for significant? If its not significant, why
worry about it?

High input impedance: dependent on circuitry.

Of course, but as a matter of course tubed circuts have far higher
input impedances.

Which is compensated for by the much karger grid voltage span.

Nope.

Yep.

Claim of superior expertise noted. Again.


Yet another red herring. BTW, the cross-modulation characteristics
of SS FM front ends are generally better than what we had when
tubes were king.

Only due to clamping diodes.

Nope. Cross modulation is about nonlinear distortion, and clamping
diodes increase that, not decrease it.

Remind me again when MOSFETs without internal clamping diodes are
available to designers.

Remind me when all SS FM front ends used MOSFETs,

Non-linear distortion, again due to the smaller BE voltage span as
compared to the larger GC span of a triode or penthode.

Apparant self-contradiction noted. Sander claims he never bypasses cathode
resistors but apparently demands that all emitter resistors be bypassed.

Granted that most tube amps have higher value input resistors.

Thanks for agreeing that your argument based on unrealistically low
grid resistors was irrelevant, Sander.

Not unrealistic at all considering my design views, but then again,
*I* am able to put off my blinders ;-)

What blinders? The vacuum tube horse has been dead in the mainstream
of hi fi for about 30 years. Putting blinders on a dead horse makes
very little sense.

Thanks anyway for discussing obsolete technology with me Arnold. ;-)

It's a waste of time, but whatever.

Actually 50 KHz or so is not an uncommon corner frequency for SS
amps.

Due to what property, exactly?

Desire to have an amp that is nice to work with.


I meant what causes the LPF character of an average SS amp?

Pole in negative feedback loop.

In what stages is that most apparent?

The whole amp. There's often a dominant pole at some lower frequency but its
LF gain is so high that its the pole in the negative feedback loop that sets
the performance of the amp.

Slewing was a problem in someone's mind by the time it was
publicized.

Since Otala, Garde et al, we know better ;-)

Yes, Otala is known to have been an alarmist, to say the least.

Otala was an optimist ;-)

OK, joke.

Back in the real world...

Besides, that is mostly a simple RC 6 dB.oct filter, not steep
enough to supress real strong RF energy.

A 6 dB/oct filter cornering at 50 KHz is down over 20 dB at 500
KHz, 40 dB at 5 MHz and 60 dB down at the 50 MHz that Mike
origionally mentioned.

One wrong grounding point may wreak havoc with that 60 dB number.

How many red herrings does this make?

What was the minimum requirement for measuring S/N again?

Signal and noise to measure....

When I once mentioned I couldn't measure better than -80 dB at one
time, you had a good laugh.

Something about being able to routinely measure signals 20-40 dB below that.

Think about a bipolar differential input, CMRR, and the actual signal
voltage needed to excurse it.

Depends on the circuit design.

You may use Google, if you like ;-)

Yawn.

"Arny Krueger" said:

My, I must be an exceptional tube amp designer ;-)

Yawn.


Do I bore you?
Just let me know, and I'll declare that I've "won" the debate and all
is good again. ;-)


First site I found with the search string tube preamp schematics:

http://www3.telus.net/public/vintage1/mu.jpg
1 meg grid resistor, bypassed cathode resistor


Keyword: vintage.


http://www3.telus.net/public/vintage1/phones.jpg
1 meg grid resistor, bypassed cathode resistor


Keyword: vintage. With a transformer!


http://www.triodeel.com/a340a.gif
220k grid resistor, bypassed cathode resistor


Keyword: vintage.


http://www.drtube.com/schematics/an/ankoru.gif
bypassed cathode resistor


Keyword: Audio Note. 'nuff said.


http://www.drtube.com/schematics/ar/d40.gif
475 k grid resistor


Mine reads 100 k in parallel with 475 k for AC.
Still high IMO.


http://www.drtube.com/schematics/ar/vt100.gif
100 K grid resistor


And a cap of 27 pF.


etc., etc.


I already granted you that most tube designs use too high values for
the first grid resistor.

There. Satisfied? ;-)


Please find a quote by me where I pretend to be an expert (or
eggsphert) in *anything* , except tinkering.

Sander wrote: " My, I must be an exceptional tube amp designer"


And that equals a claim of expertise how, exactly?

It could as well mean I'm the worst tube amp designer. ;-)


Fess up Arnold, Miller capacitance is apparent in *every*
signal-inverting amplifying device.

Can apparent be a synonum for significant? If its not significant, why
worry about it?


When you look at the definition of "Miller effect" or "Miller
capacitance", it appears clear to me that in certain cases, this
effect can NOT be neglected. Not with tubes, not with bipolars, not
with (MOS)FETs and not with IGBTs.

Tinker a lot? ;-)


Of course, but as a matter of course tubed circuts have far higher
input impedances.

Which is compensated for by the much larger grid voltage span.

in the context of RF-induced distortions

Nope.

Yep.

Claim of superior expertise noted. Again.


Nope, just experience in tinkering and repairing.


Non-linear distortion, again due to the smaller BE voltage span as
compared to the larger GC span of a triode or penthode.

Apparant self-contradiction noted. Sander claims he never bypasses cathode
resistors but apparently demands that all emitter resistors be bypassed.


Of course, the comparison ought to be unfair .

BTW you're right Arnold. ;-)


Thanks anyway for discussing obsolete technology with me Arnold. ;-)

It's a waste of time, but whatever.


Nope, it's just fun!


Actually 50 KHz or so is not an uncommon corner frequency for SS
amps.

I meant what causes the LPF character of an average SS amp?

Pole in negative feedback loop.


Only that?


In what stages is that most apparent?

The whole amp. There's often a dominant pole at some lower frequency but its
LF gain is so high that its the pole in the negative feedback loop that sets
the performance of the amp.


For the loop feedback to be effective, enough amplification at the
power bandwidth has to be there for it to be effective.

Now, if the circuit, as you seem to imply here, has very high
bandwidth, and the only reason for a SSamp to roll off at high
frequencies is the dominant pole of the feedback loop, what will
happen if some RFI signal appears at the input of the differential,
gets processed by the amp, only to find the feedback effective at the
very frequency of said signal?
Wouldn't that hang up the entire amplifier?
If yes, why isn't this effect widely known and dealt with?
If no, why do we use anti-slewing filters at inputs, and lead- and lag
networks throughout the amp?
And why are there LPFs at the outputs even?

Hint: see Otala for some explanation. ;-)


Otala was an optimist ;-)

OK, joke.

Back in the real world...


Yup. Keep a working cell phone or portophone near the back side of one
of your amplifiers.
Feed an audio signal through it and report the difference in YHD and
IM.
Now do the same with the feedback loop removed (neglecting the
absolute value of THD and IM, just the deviation).

I've done this test with some amps, tube and SS, and am willing to
discuss the results after you've seen what happens for yourself.


When I once mentioned I couldn't measure better than -80 dB at one
time, you had a good laugh.

Something about being able to routinely measure signals 20-40 dB below that.


OK, so the average 6 dB/oct filter at the input giving some 60 dB at
50 MHz attenuation, would that suffice if the RFI signal is strong?

Are signals below say 60 dB important for our perception of reproduced
music?


Think about a bipolar differential input, CMRR, and the actual signal
voltage needed to excurse it.

Depends on the circuit design.


Yes. At -60 dB, it becomes even more important. IMHO of course,
because I'm not an expert ;-)

--
Sander de Waal
" SOA of a KT88? Sufficient. "