There is a little gadget called a cheater plug, available in hardware
stores. When a power cord is plugged into the cheater plug, and the plug is
inserted into the socket so that the little ground tab on it touches
nothing, the result is frequently the elimination of stubborn hum loops.

People can talk about "black background", and related stuff I'll never
understand. But a hum loop spoils my day, and this $0.35 contraption solves
a lot of them.

Sure, people will tell you it's dangerous. If you use a cheater plug, don't
use your amp as a place to park your ass. Don't grab it while searching for
a water pipe to hold onto. Turn the system off before you make mods. In any
event, you can plug the cheater plug into a ground fault circuit
interrupter, which will provide protection similar to what the troublesome
ground connection provided, without the hum.

Robert Morein wrote:
There is a little gadget called a cheater plug, available in hardware
stores. When a power cord is plugged into the cheater plug, and the plug is
inserted into the socket so that the little ground tab on it touches
nothing, the result is frequently the elimination of stubborn hum loops.

People can talk about "black background", and related stuff I'll never
understand. But a hum loop spoils my day, and this $0.35 contraption solves
a lot of them.

Sure, people will tell you it's dangerous. If you use a cheater plug, don't
use your amp as a place to park your ass. Don't grab it while searching for
a water pipe to hold onto. Turn the system off before you make mods. In any
event, you can plug the cheater plug into a ground fault circuit
interrupter, which will provide protection similar to what the troublesome
ground connection provided, without the hum.

Please understand that I'm not trying to start a row up, but it strikes
me as
odd that someone that is comfortable doing component level repair
would advocate defeating a safety device, and not resolving the hum
issue by determining the interconnect problem most likely to be causing
the ground loop. Unfortunately. it's the unbalanced interconnects that
are
commonly used that tend to make this problem. Find the problem and
spend the money neccesary to correct it. I'm not totally sure, but the
GFCI will not protect in all current circuit failures, without the
ground
lug from the device in the circuit. I will continue to research that
issue.
Grounding is heavily discussed in the pro audio forums.
Safety is important, it doesn't take much juice to screw up the heart
beat.

Robert Morein wrote:

wrote in message
ups.com...

Robert Morein wrote:

There is a little gadget called a cheater plug, available in hardware
stores. When a power cord is plugged into the cheater plug, and the plug
is
inserted into the socket so that the little ground tab on it touches
nothing, the result is frequently the elimination of stubborn hum loops.

People can talk about "black background", and related stuff I'll never
understand. But a hum loop spoils my day, and this $0.35 contraption
solves
a lot of them.

Sure, people will tell you it's dangerous. If you use a cheater plug,
don't
use your amp as a place to park your ass. Don't grab it while searching
for
a water pipe to hold onto. Turn the system off before you make mods. In
any
event, you can plug the cheater plug into a ground fault circuit
interrupter, which will provide protection similar to what the
troublesome
ground connection provided, without the hum.

Please understand that I'm not trying to start a row up, but it strikes
me as
odd that someone that is comfortable doing component level repair
would advocate defeating a safety device, and not resolving the hum
issue by determining the interconnect problem most likely to be causing
the ground loop. Unfortunately. it's the unbalanced interconnects that
are
commonly used that tend to make this problem. Find the problem and
spend the money neccesary to correct it. I'm not totally sure, but the
GFCI will not protect in all current circuit failures, without the
ground
lug from the device in the circuit. I will continue to research that
issue.
Grounding is heavily discussed in the pro audio forums.
Safety is important, it doesn't take much juice to screw up the heart
beat.


Sometimes, hum problems cannot be solved by diligence. The ideal solution,
of course, is to replace all the equipment with stuff that has balanced
interconnects. This is not feasible for most people, including me.

The GFCI does not require the device to be grounded. It is designed to cut
the current before it can inflict harm on a human. This was one of the
first, most dramatic demonstrations of the invention.

The more pieces in a system, the more likely there are to be hum loops. I
have an 18 foot run between the low level source equipment, and the amp
rack. When I reconstructed the system, I moved a buffer preamp from the amp
rack to the source rack. This solved my problem; while previously, several
cheater plugs were required, I'm now down to a single one, for the subwoofer
amplifier. The amplifier and sub are not near anyone, and the following
would have to occur SIMULTANEOUSLY to cause a shock:
1. Equipment energized.
2 Failure in the amp.
3. Failure in the interconnect braid connections.
4. Failue in the GFCI
5. Human touches the amplifier AND, simultaneously, a source of good ground.

A lot of good equipment from the 90's, the Hafler XL series for example, has
a two wire power cord. The transformer in these units is mounted directly to
the chassis. There is no evidence of double insulation. Yet I cannot recall
a single anecdote of anyone being killed by a hifi amplifier in twenty
years. If they were, they probably weren't using a GFCI.

And by all means, try every other cure before resorting to the cheater plug.


I believe you want to have 2 prong connections for everything that
touches the amp - them the amp has 3 prongs. This way there is no
ground difference between all those units and the ground they see
through the audio/digital connections (RCA) - single ended only

wrote in message
ups.com...

Robert Morein wrote:
There is a little gadget called a cheater plug, available in hardware
stores. When a power cord is plugged into the cheater plug, and the plug
is
inserted into the socket so that the little ground tab on it touches
nothing, the result is frequently the elimination of stubborn hum loops.

People can talk about "black background", and related stuff I'll never
understand. But a hum loop spoils my day, and this $0.35 contraption
solves
a lot of them.

Sure, people will tell you it's dangerous. If you use a cheater plug,
don't
use your amp as a place to park your ass. Don't grab it while searching
for
a water pipe to hold onto. Turn the system off before you make mods. In
any
event, you can plug the cheater plug into a ground fault circuit
interrupter, which will provide protection similar to what the
troublesome
ground connection provided, without the hum.

Please understand that I'm not trying to start a row up, but it strikes
me as
odd that someone that is comfortable doing component level repair
would advocate defeating a safety device, and not resolving the hum
issue by determining the interconnect problem most likely to be causing
the ground loop. Unfortunately. it's the unbalanced interconnects that
are
commonly used that tend to make this problem. Find the problem and
spend the money neccesary to correct it. I'm not totally sure, but the
GFCI will not protect in all current circuit failures, without the
ground
lug from the device in the circuit. I will continue to research that
issue.
Grounding is heavily discussed in the pro audio forums.
Safety is important, it doesn't take much juice to screw up the heart
beat.

Sometimes, hum problems cannot be solved by diligence. The ideal solution,
of course, is to replace all the equipment with stuff that has balanced
interconnects. This is not feasible for most people, including me.

The GFCI does not require the device to be grounded. It is designed to cut
the current before it can inflict harm on a human. This was one of the
first, most dramatic demonstrations of the invention.

The more pieces in a system, the more likely there are to be hum loops. I
have an 18 foot run between the low level source equipment, and the amp
rack. When I reconstructed the system, I moved a buffer preamp from the amp
rack to the source rack. This solved my problem; while previously, several
cheater plugs were required, I'm now down to a single one, for the subwoofer
amplifier. The amplifier and sub are not near anyone, and the following
would have to occur SIMULTANEOUSLY to cause a shock:
1. Equipment energized.
2 Failure in the amp.
3. Failure in the interconnect braid connections.
4. Failue in the GFCI
5. Human touches the amplifier AND, simultaneously, a source of good ground.

A lot of good equipment from the 90's, the Hafler XL series for example, has
a two wire power cord. The transformer in these units is mounted directly to
the chassis. There is no evidence of double insulation. Yet I cannot recall
a single anecdote of anyone being killed by a hifi amplifier in twenty
years. If they were, they probably weren't using a GFCI.

And by all means, try every other cure before resorting to the cheater plug.

"MD" wrote in message
...
Robert Morein wrote:

wrote in message
ups.com...

Robert Morein wrote:

There is a little gadget called a cheater plug, available in hardware
stores. When a power cord is plugged into the cheater plug, and the plug
is
inserted into the socket so that the little ground tab on it touches
nothing, the result is frequently the elimination of stubborn hum loops.

People can talk about "black background", and related stuff I'll never
understand. But a hum loop spoils my day, and this $0.35 contraption
solves
a lot of them.

Sure, people will tell you it's dangerous. If you use a cheater plug,
don't
use your amp as a place to park your ass. Don't grab it while searching
for
a water pipe to hold onto. Turn the system off before you make mods. In
any
event, you can plug the cheater plug into a ground fault circuit
interrupter, which will provide protection similar to what the
troublesome
ground connection provided, without the hum.

Please understand that I'm not trying to start a row up, but it strikes
me as
odd that someone that is comfortable doing component level repair
would advocate defeating a safety device, and not resolving the hum
issue by determining the interconnect problem most likely to be causing
the ground loop. Unfortunately. it's the unbalanced interconnects that
are
commonly used that tend to make this problem. Find the problem and
spend the money neccesary to correct it. I'm not totally sure, but the
GFCI will not protect in all current circuit failures, without the
ground
lug from the device in the circuit. I will continue to research that
issue.
Grounding is heavily discussed in the pro audio forums.
Safety is important, it doesn't take much juice to screw up the heart
beat.


Sometimes, hum problems cannot be solved by diligence. The ideal
solution, of course, is to replace all the equipment with stuff that has
balanced interconnects. This is not feasible for most people, including
me.

The GFCI does not require the device to be grounded. It is designed to
cut the current before it can inflict harm on a human. This was one of
the first, most dramatic demonstrations of the invention.

The more pieces in a system, the more likely there are to be hum loops. I
have an 18 foot run between the low level source equipment, and the amp
rack. When I reconstructed the system, I moved a buffer preamp from the
amp rack to the source rack. This solved my problem; while previously,
several cheater plugs were required, I'm now down to a single one, for
the subwoofer amplifier. The amplifier and sub are not near anyone, and
the following would have to occur SIMULTANEOUSLY to cause a shock:
1. Equipment energized.
2 Failure in the amp.
3. Failure in the interconnect braid connections.
4. Failue in the GFCI
5. Human touches the amplifier AND, simultaneously, a source of good
ground.

A lot of good equipment from the 90's, the Hafler XL series for example,
has a two wire power cord. The transformer in these units is mounted
directly to the chassis. There is no evidence of double insulation. Yet I
cannot recall a single anecdote of anyone being killed by a hifi
amplifier in twenty years. If they were, they probably weren't using a
GFCI.

And by all means, try every other cure before resorting to the cheater
plug.
I believe you want to have 2 prong connections for everything that touches
the amp - them the amp has 3 prongs. This way there is no ground
difference between all those units and the ground they see through the
audio/digital connections (RCA) - single ended only

IME, this is not de facto necessary. I get away with a mix of:
1. double-insulated Sony equipment
2. older Halfer equipment, which is not double insulated, and has two wire
plugs.
3. three wire grounded equipment.

There is a 6th level of protection, which is human awareness.

"François Yves Le Gal" wrote in message
...
On Sun, 19 Mar 2006 10:31:40 -0500, "Robert Morein"
wrote:

The GFCI does not require the device to be grounded.

A GFCI i- for ground-fault circuit-interrupter - s a friggin' device, not
a
norm. You may only use one if you don't have a properly grounded mains
circuit.

Francois, are you perhaps misphrasing this? A GFCI is effective only if it
is connected to a mains circuit with a 3rd wire ground.


If you live in the US of A, check the National Electrical Code for proper
info.

BTW, if an equipment has been designed for 2+1 grounded operation, it's
particularly stupid and dangerous to use a cheater.

It is not stupid. It does require awareness of the operator. My amplifier is
not located near a ground that could be accidentally touched. There is no
evidence that it is a signficant cause of loss of life.

A hazard is not a hazard just because a code declares it so. Driving a car
is much more dangerous than using a cheater plug. The attempt to remove all
hazards from our lives, regardless of the relative danger they present, is
fruitless. In the end, we all die, most probably in bed.

wrote in message
oups.com...
Robert Morein wrote :

There is a little gadget called a cheater plug, available in hardware
stores. When a power cord is plugged into the cheater plug, and the plug
is
inserted into the socket so that the little ground tab on it touches
nothing, the result is frequently the elimination of stubborn hum loops.

People can talk about "black background", and related stuff I'll never
understand. But a hum loop spoils my day, and this $0.35 contraption
solves
a lot of them.

Sure, people will tell you it's dangerous. If you use a cheater plug,
don't
use your amp as a place to park your ass. Don't grab it while searching
for
a water pipe to hold onto. Turn the system off before you make mods. In
any
event, you can plug the cheater plug into a ground fault circuit
interrupter, which will provide protection similar to what the
troublesome
ground connection provided, without the hum.

I expected pretty soon you're going to get "Trevor The Troll" Wilson to
come along and write:

*WARNING! *WARNING! *WARNING! *WARNING! This advice may do several
things:

* KILL you and your loved ones
* DESTROY your amplifier and everything you cherish and own
* SEND YOUR INSURANCE PREMIUMS through the roof
* TURN YOU INTO a pariah in the community, and cause you to be
ex-communicated

Of course. But in order to enjoy life to it's fullest, we musn't get caught
up in possibilities that are almost hypothetical. Perhaps one audiophile has
been killed in the past 20 years by an electric short, while 1000 have died
in car crashes, and 100,000 from old age.

Singling out hypothetical hazards will neither increase our life
expetancies, or our enjoyment of life. Eventually, most of us will die in
bed.

And, I repeat: don't use the cheater plug until all economically viable
solutions have been explored. And be careful.

"François Yves Le Gal" wrote in message
...
On Sun, 19 Mar 2006 12:05:23 -0500, "Robert Morein"
wrote:

Francois, are you perhaps misphrasing this? A GFCI is effective only if it
is connected to a mains circuit with a 3rd wire ground.

Nope, a GFCI is basically a breaker. Re-read NEC 406.3(D)(2) regarding
the
installtion of GFCI's in a "No Equipment Ground" context. It works with or
without a grounding wire.

Impossible. A GFCI senses current on the ground. Without a valid 3rd wire,
it has no way to differentiate between normal mode from hot to neutral, and
leakage to ground.


BTW, if you happen to miswire a GFCI with a line/load reversal, the
receptacle face will *always* be live, defeating it's purpose and
transforming it into yet another hazard.

Let's not do that.

"Robert Morein" wrote in message
...

"François Yves Le Gal" wrote in message
...
On Sun, 19 Mar 2006 12:05:23 -0500, "Robert Morein"
wrote:

Francois, are you perhaps misphrasing this? A GFCI is effective only if
it
is connected to a mains circuit with a 3rd wire ground.

Nope, a GFCI is basically a breaker. Re-read NEC 406.3(D)(2) regarding
the
installtion of GFCI's in a "No Equipment Ground" context. It works with
or
without a grounding wire.

Impossible. A GFCI senses current on the ground. Without a valid 3rd wire,
it has no way to differentiate between normal mode from hot to neutral,
and leakage to ground.

Actually they sense the current difference between hot and neutral.
Any significant difference and they trip.
U/L only allows something like 10% of the power to leak into the Ground line
if it exists.

So a GFCI will work on a 2 prong device.

http://www.codecheck.com/gfci_principal.htm

I don't agree that its a good idea to use cheater plugs...ever.
There are other ways to solve ground loops.

ScottW

wrote in message
oups.com...
Another thing that's even easier than installing a cheater, is to
simply check the polarity of all of your plugs that can be reversed. A
lot of people don't think to do that (especially ignorant old dinosaurs
like Arny Krueger, who don't even believe polarity has any audible
effect). I use music to test for correct polarity. Certain music is
better for checking proper polarity than just anything. Often, I'll
take out my Sheffield Track Record LP (or CD) to test for polarity (or
my Chesky Test CD, which has a trumpet track for polarity testing), by
hearing how the drum is struck. It will sound right (properly struck)
when the plug is correctly inserted, and wrong (inverted) when it
isn't.

Been there done that, no effect.

A freind of mine who was a TAS/Stereophile dogmatist, thought he'd
investigate this "tweak" and yes he did use music. I happened to be at his
place when he was in the process of trying this out, so I had the
opportunity to let him hear the difference between the "proper "
polorization and the not give a crap version. So without heim knowing which
was which I wouold switch between them and he would listen. No effect that
he could determine.

"François Yves Le Gal" wrote in message
news
On Sun, 19 Mar 2006 13:07:25 -0500, "Robert Morein"
wrote:

Nope, a GFCI is basically a breaker. Re-read NEC 406.3(D)(2) regarding
the
installtion of GFCI's in a "No Equipment Ground" context. It works with
or
without a grounding wire.

Impossible. A GFCI senses current on the ground. Without a valid 3rd wire,
it has no way to differentiate between normal mode from hot to neutral,
and
leakage to ground.

You need to brush up your Electricity 101...

"Where no grounding means exists at an outlet box, a non-grounding
receptacle may be replaced with a grounding-type GFI receptacle with no
ground connection. The receptacle must be marked "no equipment ground".
If
the GFI protects additional loads, a ground wire must not be connected to
the supplied loads."
406.3(d)(3)(b)


"Where no grounding means exists at an outlet box, a non-grounding
receptacle may be replaced with a grounding-type receptacle with no ground
connection if it is protected by a GFI. The receptacle must be marked "no
equipment ground" and "GFI protected". A ground wire must not be
connected
between grounding-type receptacles so used."
406.3(d)(3)(c)

Your correction is gratefully accepted.

"ScottW" wrote in message
news:FnhTf.138824$0G.125505@dukeread10...

"Robert Morein" wrote in message
...

"François Yves Le Gal" wrote in message
...
On Sun, 19 Mar 2006 12:05:23 -0500, "Robert Morein"

wrote:

Francois, are you perhaps misphrasing this? A GFCI is effective only if
it
is connected to a mains circuit with a 3rd wire ground.

Nope, a GFCI is basically a breaker. Re-read NEC 406.3(D)(2) regarding
the
installtion of GFCI's in a "No Equipment Ground" context. It works with
or
without a grounding wire.

Impossible. A GFCI senses current on the ground. Without a valid 3rd
wire, it has no way to differentiate between normal mode from hot to
neutral, and leakage to ground.

Actually they sense the current difference between hot and neutral.
Any significant difference and they trip.
U/L only allows something like 10% of the power to leak into the Ground
line if it exists.

So a GFCI will work on a 2 prong device.

http://www.codecheck.com/gfci_principal.htm

I don't agree that its a good idea to use cheater plugs...ever.
There are other ways to solve ground loops.

ScottW
Hey, Scott, it's your choice if you want to suffer.

:

wrote in message
oups.com...
Another thing that's even easier than installing a cheater, is to
simply check the polarity of all of your plugs that can be reversed. A
lot of people don't think to do that (especially ignorant old dinosaurs
like Arny Krueger, who don't even believe polarity has any audible
effect). I use music to test for correct polarity. Certain music is
better for checking proper polarity than just anything. Often, I'll
take out my Sheffield Track Record LP (or CD) to test for polarity (or
my Chesky Test CD, which has a trumpet track for polarity testing), by
hearing how the drum is struck. It will sound right (properly struck)
when the plug is correctly inserted, and wrong (inverted) when it
isn't.

Been there done that, no effect.

A freind of mine who was a TAS/Stereophile dogmatist, thought he'd
investigate this "tweak" and yes he did use music. I happened to be at his
place when he was in the process of trying this out, so I had the
opportunity to let him hear the difference between the "proper "
polorization and the not give a crap version. So without heim knowing which
was which I wouold switch between them and he would listen. No effect that
he could determine.

So? You've proven that you and your friend are insensitive
listeners,whereas a million other people can hear polarity. Did you
have a point?

wrote in message
ink.net...

wrote in message
oups.com...
Another thing that's even easier than installing a cheater, is to
simply check the polarity of all of your plugs that can be reversed. A
lot of people don't think to do that (especially ignorant old dinosaurs
like Arny Krueger, who don't even believe polarity has any audible
effect). I use music to test for correct polarity. Certain music is
better for checking proper polarity than just anything. Often, I'll
take out my Sheffield Track Record LP (or CD) to test for polarity (or
my Chesky Test CD, which has a trumpet track for polarity testing), by
hearing how the drum is struck. It will sound right (properly struck)
when the plug is correctly inserted, and wrong (inverted) when it
isn't.

Been there done that, no effect.

A freind of mine who was a TAS/Stereophile dogmatist, thought he'd
investigate this "tweak" and yes he did use music. I happened to be at
his place when he was in the process of trying this out, so I had the
opportunity to let him hear the difference between the "proper "
polorization and the not give a crap version. So without heim knowing
which was which I wouold switch between them and he would listen. No
effect that he could determine.
With all due respect to Sounhaspriority, I tend to agree -- except for one
thing.
The plug orientation will change the degree of capacitive coupling to the
core. Hence, the well known phenomena that the orientation of the plug can
affect the amount of hum in the circuit.

said:


wrote in message
roups.com...
Another thing that's even easier than installing a cheater, is to
simply check the polarity of all of your plugs that can be reversed. A
lot of people don't think to do that (especially ignorant old dinosaurs
like Arny Krueger, who don't even believe polarity has any audible
effect). I use music to test for correct polarity. Certain music is
better for checking proper polarity than just anything. Often, I'll
take out my Sheffield Track Record LP (or CD) to test for polarity (or
my Chesky Test CD, which has a trumpet track for polarity testing), by
hearing how the drum is struck. It will sound right (properly struck)
when the plug is correctly inserted, and wrong (inverted) when it
isn't.


Been there done that, no effect.


A freind of mine who was a TAS/Stereophile dogmatist, thought he'd
investigate this "tweak" and yes he did use music. I happened to be at his
place when he was in the process of trying this out, so I had the
opportunity to let him hear the difference between the "proper "
polorization and the not give a crap version. So without heim knowing which
was which I wouold switch between them and he would listen. No effect that
he could determine.


There is, however, a possible technical reason for checking the
polarity of mains cables: the mains transformer has a certain capacity
from core to ground, chassis and encasing.
If you reverse the plug (here in Holland that's possible even with
earthed plugs), there may be a different current flowing from live to
case (very smallish, but still).

Because in general, in consumer electronics, grounds are connected via
the ground wire or screen of interconnects, these currents will flow
through the screens of the interconnects.
With sensitive gear, this may well result in a higher S/N ratio.
This is easily measurable, and sometimes even audible.

One reason more to use real symmetrical XLR connections and cables.

--

- Never argue with idiots, they drag you down their level and beat you with experience. -

Sander deWaal wrote:
said:


wrote in message
roups.com...
Another thing that's even easier than installing a cheater, is to
simply check the polarity of all of your plugs that can be reversed. A
lot of people don't think to do that (especially ignorant old dinosaurs
like Arny Krueger, who don't even believe polarity has any audible
effect). I use music to test for correct polarity. Certain music is
better for checking proper polarity than just anything. Often, I'll
take out my Sheffield Track Record LP (or CD) to test for polarity (or
my Chesky Test CD, which has a trumpet track for polarity testing), by
hearing how the drum is struck. It will sound right (properly struck)
when the plug is correctly inserted, and wrong (inverted) when it
isn't.


Been there done that, no effect.


A freind of mine who was a TAS/Stereophile dogmatist, thought he'd
investigate this "tweak" and yes he did use music. I happened to be at his
place when he was in the process of trying this out, so I had the
opportunity to let him hear the difference between the "proper "
polorization and the not give a crap version. So without heim knowing which
was which I wouold switch between them and he would listen. No effect that
he could determine.


There is, however, a possible technical reason for checking the
polarity of mains cables: the mains transformer has a certain capacity
from core to ground, chassis and encasing.
If you reverse the plug (here in Holland that's possible even with
earthed plugs), there may be a different current flowing from live to
case (very smallish, but still).

Because in general, in consumer electronics, grounds are connected via
the ground wire or screen of interconnects, these currents will flow
through the screens of the interconnects.
With sensitive gear, this may well result in a higher S/N ratio.
This is easily measurable, and sometimes even audible.

One reason more to use real symmetrical XLR connections and cables.

--

- Never argue with idiots, they drag you down their level and beat you with experience. -

I'm not familiar with Euro electrical standards.
In the states it's not unusual to have a small (mv) current on the
neutral
relative to the ground or earthed connection from a lighting dimmer
or touch lamp or motor.
If it exceeds a volt or two then it becomes an audible problem.
The transformers I have encountered have always had the winding
connected between hot and neutral. Core grounded to chassis.
If the chassis is grounded to the earth at the AC power source
by the power cord or a separate third wire to the power strip,
how does reversing hot and neutral improve the situation?
This is not to be confused with reversing the polarity of speaker
connections, which is a phase issue (_ _ _'s speakers suck) :-)

"Robert Morein" wrote in message
...

"ScottW" wrote in message
news:FnhTf.138824$0G.125505@dukeread10...

"Robert Morein" wrote in message
...

"François Yves Le Gal" wrote in message
...
On Sun, 19 Mar 2006 12:05:23 -0500, "Robert Morein"

wrote:

Francois, are you perhaps misphrasing this? A GFCI is effective only if
it
is connected to a mains circuit with a 3rd wire ground.

Nope, a GFCI is basically a breaker. Re-read NEC 406.3(D)(2) regarding
the
installtion of GFCI's in a "No Equipment Ground" context. It works with
or
without a grounding wire.

Impossible. A GFCI senses current on the ground. Without a valid 3rd
wire, it has no way to differentiate between normal mode from hot to
neutral, and leakage to ground.

Actually they sense the current difference between hot and neutral.
Any significant difference and they trip.
U/L only allows something like 10% of the power to leak into the Ground
line if it exists.

So a GFCI will work on a 2 prong device.

http://www.codecheck.com/gfci_principal.htm

I don't agree that its a good idea to use cheater plugs...ever.
There are other ways to solve ground loops.

ScottW
Hey, Scott, it's your choice if you want to suffer.

Only thing I'm suffering is your ignorance.
Enjoy your wiring nightmare....oh yes, and in the event
of fire...be sure not to let the insurance company know what
you did... they kind of frown on stuff like that.

ScottW

wrote in message
oups.com...

Sander deWaal wrote:
said:


wrote in message
roups.com...
Another thing that's even easier than installing a cheater, is to
simply check the polarity of all of your plugs that can be reversed. A
lot of people don't think to do that (especially ignorant old
dinosaurs
like Arny Krueger, who don't even believe polarity has any audible
effect). I use music to test for correct polarity. Certain music is
better for checking proper polarity than just anything. Often, I'll
take out my Sheffield Track Record LP (or CD) to test for polarity (or
my Chesky Test CD, which has a trumpet track for polarity testing), by
hearing how the drum is struck. It will sound right (properly struck)
when the plug is correctly inserted, and wrong (inverted) when it
isn't.


Been there done that, no effect.


A freind of mine who was a TAS/Stereophile dogmatist, thought he'd
investigate this "tweak" and yes he did use music. I happened to be at
his
place when he was in the process of trying this out, so I had the
opportunity to let him hear the difference between the "proper "
polorization and the not give a crap version. So without heim knowing
which
was which I wouold switch between them and he would listen. No effect
that
he could determine.


There is, however, a possible technical reason for checking the
polarity of mains cables: the mains transformer has a certain capacity
from core to ground, chassis and encasing.
If you reverse the plug (here in Holland that's possible even with
earthed plugs), there may be a different current flowing from live to
case (very smallish, but still).

Because in general, in consumer electronics, grounds are connected via
the ground wire or screen of interconnects, these currents will flow
through the screens of the interconnects.
With sensitive gear, this may well result in a higher S/N ratio.
This is easily measurable, and sometimes even audible.

One reason more to use real symmetrical XLR connections and cables.

--

- Never argue with idiots, they drag you down their level and beat you
with experience. -

I'm not familiar with Euro electrical standards.
In the states it's not unusual to have a small (mv) current on the
neutral
relative to the ground or earthed connection from a lighting dimmer
or touch lamp or motor.
If it exceeds a volt or two then it becomes an audible problem.
The transformers I have encountered have always had the winding
connected between hot and neutral. Core grounded to chassis.
If the chassis is grounded to the earth at the AC power source
by the power cord or a separate third wire to the power strip,
how does reversing hot and neutral improve the situation?

I think he's saying if you floated chassis ground and reverse
hot and neutral you could cause an increase in ground current
through your signal ground to another piece of gear to
earth ground. That signal ground current flow can cause
noise with single ended ...so...ideally you should make sure your power
polarity (hot and neutral...IIRC hot is the smaller slot in a 110
outlet) and most plugs are now polarized (one small prong and
one wide)

This is not to be confused with reversing the polarity of speaker
connections, which is a phase issue (_ _ _'s speakers suck) :-)

Which is also not to be confused with signal polarity .

ScottW

"ScottW" wrote in message
news:Z3jTf.138830$0G.36110@dukeread10...

"Robert Morein" wrote in message
...

"ScottW" wrote in message
news:FnhTf.138824$0G.125505@dukeread10...

"Robert Morein" wrote in message
...

"François Yves Le Gal" wrote in message
...
On Sun, 19 Mar 2006 12:05:23 -0500, "Robert Morein"

wrote:

Francois, are you perhaps misphrasing this? A GFCI is effective only
if it
is connected to a mains circuit with a 3rd wire ground.

Nope, a GFCI is basically a breaker. Re-read NEC 406.3(D)(2)
regarding the
installtion of GFCI's in a "No Equipment Ground" context. It works
with or
without a grounding wire.

Impossible. A GFCI senses current on the ground. Without a valid 3rd
wire, it has no way to differentiate between normal mode from hot to
neutral, and leakage to ground.

Actually they sense the current difference between hot and neutral.
Any significant difference and they trip.
U/L only allows something like 10% of the power to leak into the Ground
line if it exists.

So a GFCI will work on a 2 prong device.

http://www.codecheck.com/gfci_principal.htm

I don't agree that its a good idea to use cheater plugs...ever.
There are other ways to solve ground loops.

ScottW
Hey, Scott, it's your choice if you want to suffer.

Only thing I'm suffering is your ignorance.
Enjoy your wiring nightmare....oh yes, and in the event
of fire...be sure not to let the insurance company know what
you did... they kind of frown on stuff like that.

ScottW
Anybody ever hear of a hifi amplifier causing a house fire? If so, how many
in thirty years?

said:


I'm not familiar with Euro electrical standards.
In the states it's not unusual to have a small (mv) current on the
neutral
relative to the ground or earthed connection from a lighting dimmer
or touch lamp or motor.
If it exceeds a volt or two then it becomes an audible problem.
The transformers I have encountered have always had the winding
connected between hot and neutral. Core grounded to chassis.
If the chassis is grounded to the earth at the AC power source
by the power cord or a separate third wire to the power strip,
how does reversing hot and neutral improve the situation?
This is not to be confused with reversing the polarity of speaker
connections, which is a phase issue (_ _ _'s speakers suck) :-)


Most commercial gear I see, have mains cables without PE.
Here in Holland, they can go bot ways into the socket.

ScottW and François both explained it better than I did.

--

- Never argue with idiots, they drag you down their level and beat you with experience. -

"François Yves Le Gal" wrote in message
...
On Sun, 19 Mar 2006 16:03:31 -0500, "Robert Morein"
wrote:

Anybody ever hear of a hifi amplifier causing a house fire? If so, how
many
in thirty years?

It's actually pretty common, with hundreds - if not thousands - of fires
induced by AV equipment each year.

Televisions are the most dangerous A/V appliances, because of the ability of
high voltage to produce a substantial arc. You have to factor that out of
A/V statistics. I don't believe stereo equipment is very dangerous. Please
produce some hard statistics to the contrary. And remember, those stats may
contain boomboxes in combustible plastic cabinets. That is not the subject
of discussion in this thread.

Also, it should be noted that the incidence of fire has no relationship to
the presence of a chassis ground. You can theorize, but I doubt the
statistics break it out. The vast majority of A/V equipment made in the past
20 years is manufactured to the so-called "double insulated standard", where
chassis ground is simply not an issue. The issue with that equipment is the
circuit board material, typically epoxy paper, and the considerable use of
plastics.

The amplifiers for which I suggest the cheater plug -- as a last resort, of
course -- are typically massively made. The Parasound which did have bypass
cap ignition is completely encased in metal; the boards are FR-4. The
ignition occurred irrespective of the fact that the Parasound, in fact, does
not have a cheater plug.

wrote in message
oups.com...

Sander deWaal wrote:
said:


wrote in message
roups.com...
Another thing that's even easier than installing a cheater, is to
simply check the polarity of all of your plugs that can be reversed. A
lot of people don't think to do that (especially ignorant old
dinosaurs
like Arny Krueger, who don't even believe polarity has any audible
effect). I use music to test for correct polarity. Certain music is
better for checking proper polarity than just anything. Often, I'll
take out my Sheffield Track Record LP (or CD) to test for polarity (or
my Chesky Test CD, which has a trumpet track for polarity testing), by
hearing how the drum is struck. It will sound right (properly struck)
when the plug is correctly inserted, and wrong (inverted) when it
isn't.


Been there done that, no effect.


A freind of mine who was a TAS/Stereophile dogmatist, thought he'd
investigate this "tweak" and yes he did use music. I happened to be at
his
place when he was in the process of trying this out, so I had the
opportunity to let him hear the difference between the "proper "
polorization and the not give a crap version. So without heim knowing
which
was which I wouold switch between them and he would listen. No effect
that
he could determine.


There is, however, a possible technical reason for checking the
polarity of mains cables: the mains transformer has a certain capacity
from core to ground, chassis and encasing.
If you reverse the plug (here in Holland that's possible even with
earthed plugs), there may be a different current flowing from live to
case (very smallish, but still).

Because in general, in consumer electronics, grounds are connected via
the ground wire or screen of interconnects, these currents will flow
through the screens of the interconnects.
With sensitive gear, this may well result in a higher S/N ratio.
This is easily measurable, and sometimes even audible.

One reason more to use real symmetrical XLR connections and cables.

--

- Never argue with idiots, they drag you down their level and beat you
with experience. -

I'm not familiar with Euro electrical standards.
In the states it's not unusual to have a small (mv) current on the
neutral
relative to the ground or earthed connection from a lighting dimmer
or touch lamp or motor.
If it exceeds a volt or two then it becomes an audible problem.
The transformers I have encountered have always had the winding
connected between hot and neutral. Core grounded to chassis.
If the chassis is grounded to the earth at the AC power source
by the power cord or a separate third wire to the power strip,
how does reversing hot and neutral improve the situation?
This is not to be confused with reversing the polarity of speaker
connections, which is a phase issue (_ _ _'s speakers suck) :-)

It doesn't. It comes into play with older equipment, with two wire,
unpolarized ground cords. In that case, inserting the plug the "wrong" way
will put the side of the winding connected to "hot" in close proximity with
the core.

wrote in message
ink.net...

wrote in message
oups.com...
Another thing that's even easier than installing a cheater, is to
simply check the polarity of all of your plugs that can be reversed. A
lot of people don't think to do that (especially ignorant old dinosaurs
like Arny Krueger, who don't even believe polarity has any audible
effect). I use music to test for correct polarity. Certain music is
better for checking proper polarity than just anything. Often, I'll
take out my Sheffield Track Record LP (or CD) to test for polarity (or
my Chesky Test CD, which has a trumpet track for polarity testing), by
hearing how the drum is struck. It will sound right (properly struck)
when the plug is correctly inserted, and wrong (inverted) when it
isn't.

Been there done that, no effect.

A freind of mine who was a TAS/Stereophile dogmatist, thought he'd
investigate this "tweak" and yes he did use music. I happened to be at
his place when he was in the process of trying this out, so I had the
opportunity to let him hear the difference between the "proper "
polorization and the not give a crap version. So without heim knowing
which was which I wouold switch between them and he would listen. No
effect that he could determine.


AS to abslute polarity, it is more evident on some recordings than others.
Consider that all sorts of lesser polarity inversions can occur in the
recordng process.
Certain tracks on a cut may be out of absolute polarity with other tracks,
and then mixed.
So, the absolute polarity of the recording may become shmeared and
indistinct.
One track might be out of absolute polarity with the remaining tracks.
I hav some cd's that are absolutely inverted in their absolute polarity!



--
Posted via NewsDemon.com - Premium Uncensored Newsgroup Service
-------http://www.NewsDemon.com------
Unlimited Access, Anonymous Accounts, Uncensored Broadband Access

wrote in message
oups.com...

Sander deWaal wrote:
said:


wrote in message
roups.com...
Another thing that's even easier than installing a cheater, is to
simply check the polarity of all of your plugs that can be reversed. A
lot of people don't think to do that (especially ignorant old
dinosaurs
like Arny Krueger, who don't even believe polarity has any audible
effect). I use music to test for correct polarity. Certain music is
better for checking proper polarity than just anything. Often, I'll
take out my Sheffield Track Record LP (or CD) to test for polarity (or
my Chesky Test CD, which has a trumpet track for polarity testing), by
hearing how the drum is struck. It will sound right (properly struck)
when the plug is correctly inserted, and wrong (inverted) when it
isn't.


Been there done that, no effect.


A freind of mine who was a TAS/Stereophile dogmatist, thought he'd
investigate this "tweak" and yes he did use music. I happened to be at
his
place when he was in the process of trying this out, so I had the
opportunity to let him hear the difference between the "proper "
polorization and the not give a crap version. So without heim knowing
which
was which I wouold switch between them and he would listen. No effect
that
he could determine.


There is, however, a possible technical reason for checking the
polarity of mains cables: the mains transformer has a certain capacity
from core to ground, chassis and encasing.
If you reverse the plug (here in Holland that's possible even with
earthed plugs), there may be a different current flowing from live to
case (very smallish, but still).

Because in general, in consumer electronics, grounds are connected via
the ground wire or screen of interconnects, these currents will flow
through the screens of the interconnects.
With sensitive gear, this may well result in a higher S/N ratio.
This is easily measurable, and sometimes even audible.

One reason more to use real symmetrical XLR connections and cables.

--

- Never argue with idiots, they drag you down their level and beat you
with experience. -

I'm not familiar with Euro electrical standards.
In the states it's not unusual to have a small (mv) current on the
neutral
relative to the ground or earthed connection from a lighting dimmer
or touch lamp or motor.
If it exceeds a volt or two then it becomes an audible problem.
The transformers I have encountered have always had the winding
connected between hot and neutral. Core grounded to chassis.
If the chassis is grounded to the earth at the AC power source
by the power cord or a separate third wire to the power strip,
how does reversing hot and neutral improve the situation?
This is not to be confused with reversing the polarity of speaker
connections, which is a phase issue (_ _ _'s speakers suck) :-)


It is tobe so confused, if you invert the polarity of all the speakers.



--
Posted via NewsDemon.com - Premium Uncensored Newsgroup Service
-------http://www.NewsDemon.com------
Unlimited Access, Anonymous Accounts, Uncensored Broadband Access

"ScottW" wrote in message
news:TljTf.138833$0G.106251@dukeread10...

wrote in message
oups.com...

Sander deWaal wrote:
said:


wrote in message
roups.com...
Another thing that's even easier than installing a cheater, is to
simply check the polarity of all of your plugs that can be reversed.
A
lot of people don't think to do that (especially ignorant old
dinosaurs
like Arny Krueger, who don't even believe polarity has any audible
effect). I use music to test for correct polarity. Certain music is
better for checking proper polarity than just anything. Often, I'll
take out my Sheffield Track Record LP (or CD) to test for polarity
(or
my Chesky Test CD, which has a trumpet track for polarity testing),
by
hearing how the drum is struck. It will sound right (properly struck)
when the plug is correctly inserted, and wrong (inverted) when it
isn't.


Been there done that, no effect.


A freind of mine who was a TAS/Stereophile dogmatist, thought he'd
investigate this "tweak" and yes he did use music. I happened to be at
his
place when he was in the process of trying this out, so I had the
opportunity to let him hear the difference between the "proper "
polorization and the not give a crap version. So without heim knowing
which
was which I wouold switch between them and he would listen. No effect
that
he could determine.


There is, however, a possible technical reason for checking the
polarity of mains cables: the mains transformer has a certain capacity
from core to ground, chassis and encasing.
If you reverse the plug (here in Holland that's possible even with
earthed plugs), there may be a different current flowing from live to
case (very smallish, but still).

Because in general, in consumer electronics, grounds are connected via
the ground wire or screen of interconnects, these currents will flow
through the screens of the interconnects.
With sensitive gear, this may well result in a higher S/N ratio.
This is easily measurable, and sometimes even audible.

One reason more to use real symmetrical XLR connections and cables.

--

- Never argue with idiots, they drag you down their level and beat you
with experience. -

I'm not familiar with Euro electrical standards.
In the states it's not unusual to have a small (mv) current on the
neutral
relative to the ground or earthed connection from a lighting dimmer
or touch lamp or motor.
If it exceeds a volt or two then it becomes an audible problem.
The transformers I have encountered have always had the winding
connected between hot and neutral. Core grounded to chassis.
If the chassis is grounded to the earth at the AC power source
by the power cord or a separate third wire to the power strip,
how does reversing hot and neutral improve the situation?

I think he's saying if you floated chassis ground and reverse
hot and neutral you could cause an increase in ground current
through your signal ground to another piece of gear to
earth ground. That signal ground current flow can cause
noise with single ended ...so...ideally you should make sure your power
polarity (hot and neutral...IIRC hot is the smaller slot in a 110
outlet) and most plugs are now polarized (one small prong and
one wide)

This is not to be confused with reversing the polarity of speaker
connections, which is a phase issue (_ _ _'s speakers suck) :-)

Which is also not to be confused with signal polarity .


To clear up any confusion, that's what I was talking about.



--
Posted via NewsDemon.com - Premium Uncensored Newsgroup Service
-------http://www.NewsDemon.com------
Unlimited Access, Anonymous Accounts, Uncensored Broadband Access

"François Yves Le Gal" wrote in
message

On Sun, 19 Mar 2006 10:31:40 -0500, "Robert Morein"
wrote:

The GFCI does not require the device to be grounded.

A GFCI i- for ground-fault circuit-interrupter - s a
friggin' device, not a norm. You may only use one if you
don't have a properly grounded mains circuit.

GFCIs are routinely used in the US on properly grounded mains circuits. For
example, GFCIs are required on all outlets that are within touching
distances of a sink (I think that's 6'), and they're required on all outlets
in a garage that are less than 8' above the floor.

If you live in the US of A, check the National Electrical
Code for proper info.

Agreed.

BTW, if an equipment has been designed for 2+1 grounded
operation, it's particularly stupid and dangerous to use
a cheater.

Totally agreed. The best thing to do about ground loops is to cure them at
their source.

"François Yves Le Gal" wrote in
message
On Sun, 19 Mar 2006 12:05:23 -0500, "Robert Morein"
wrote:

Francois, are you perhaps misphrasing this? A GFCI is
effective only if it is connected to a mains circuit
with a 3rd wire ground.

Nope, a GFCI is basically a breaker. Re-read NEC
406.3(D)(2) regarding the installtion of GFCI's in a "No
Equipment Ground" context. It works with or without a
grounding wire.

This is completely true. A GFCI works by tripping whenever the current flow
through the hot and neutral sides of the circuit passing through it are
slightly unbalanced.

Clyde Slick wrote:
wrote in message
oups.com...

Sander deWaal wrote:
said:


wrote in message
roups.com...
Another thing that's even easier than installing a cheater, is to
simply check the polarity of all of your plugs that can be reversed. A
lot of people don't think to do that (especially ignorant old
dinosaurs
like Arny Krueger, who don't even believe polarity has any audible
effect). I use music to test for correct polarity. Certain music is
better for checking proper polarity than just anything. Often, I'll
take out my Sheffield Track Record LP (or CD) to test for polarity (or
my Chesky Test CD, which has a trumpet track for polarity testing), by
hearing how the drum is struck. It will sound right (properly struck)
when the plug is correctly inserted, and wrong (inverted) when it
isn't.


Been there done that, no effect.


A freind of mine who was a TAS/Stereophile dogmatist, thought he'd
investigate this "tweak" and yes he did use music. I happened to be at
his
place when he was in the process of trying this out, so I had the
opportunity to let him hear the difference between the "proper "
polorization and the not give a crap version. So without heim knowing
which
was which I wouold switch between them and he would listen. No effect
that
he could determine.


There is, however, a possible technical reason for checking the
polarity of mains cables: the mains transformer has a certain capacity
from core to ground, chassis and encasing.
If you reverse the plug (here in Holland that's possible even with
earthed plugs), there may be a different current flowing from live to
case (very smallish, but still).

Because in general, in consumer electronics, grounds are connected via
the ground wire or screen of interconnects, these currents will flow
through the screens of the interconnects.
With sensitive gear, this may well result in a higher S/N ratio.
This is easily measurable, and sometimes even audible.

One reason more to use real symmetrical XLR connections and cables.

--

- Never argue with idiots, they drag you down their level and beat you
with experience. -

I'm not familiar with Euro electrical standards.
In the states it's not unusual to have a small (mv) current on the
neutral
relative to the ground or earthed connection from a lighting dimmer
or touch lamp or motor.
If it exceeds a volt or two then it becomes an audible problem.
The transformers I have encountered have always had the winding
connected between hot and neutral. Core grounded to chassis.
If the chassis is grounded to the earth at the AC power source
by the power cord or a separate third wire to the power strip,
how does reversing hot and neutral improve the situation?
This is not to be confused with reversing the polarity of speaker
connections, which is a phase issue (_ _ _'s speakers suck) :-)


It is tobe so confused, if you invert the polarity of all the speakers.



--
Posted via NewsDemon.com - Premium Uncensored Newsgroup Service
-------http://www.NewsDemon.com------
Unlimited Access, Anonymous Accounts, Uncensored Broadband Access

Clyde Slick wrote:
wrote in message
oups.com...

Sander deWaal wrote:
said:


wrote in message
roups.com...
Another thing that's even easier than installing a cheater, is to
simply check the polarity of all of your plugs that can be reversed. A
lot of people don't think to do that (especially ignorant old
dinosaurs
like Arny Krueger, who don't even believe polarity has any audible
effect). I use music to test for correct polarity. Certain music is
better for checking proper polarity than just anything. Often, I'll
take out my Sheffield Track Record LP (or CD) to test for polarity (or
my Chesky Test CD, which has a trumpet track for polarity testing), by
hearing how the drum is struck. It will sound right (properly struck)
when the plug is correctly inserted, and wrong (inverted) when it
isn't.


Been there done that, no effect.


A freind of mine who was a TAS/Stereophile dogmatist, thought he'd
investigate this "tweak" and yes he did use music. I happened to be at
his
place when he was in the process of trying this out, so I had the
opportunity to let him hear the difference between the "proper "
polorization and the not give a crap version. So without heim knowing
which
was which I wouold switch between them and he would listen. No effect
that
he could determine.


There is, however, a possible technical reason for checking the
polarity of mains cables: the mains transformer has a certain capacity
from core to ground, chassis and encasing.
If you reverse the plug (here in Holland that's possible even with
earthed plugs), there may be a different current flowing from live to
case (very smallish, but still).

Because in general, in consumer electronics, grounds are connected via
the ground wire or screen of interconnects, these currents will flow
through the screens of the interconnects.
With sensitive gear, this may well result in a higher S/N ratio.
This is easily measurable, and sometimes even audible.

One reason more to use real symmetrical XLR connections and cables.

--

- Never argue with idiots, they drag you down their level and beat you
with experience. -

I'm not familiar with Euro electrical standards.
In the states it's not unusual to have a small (mv) current on the
neutral
relative to the ground or earthed connection from a lighting dimmer
or touch lamp or motor.
If it exceeds a volt or two then it becomes an audible problem.
The transformers I have encountered have always had the winding
connected between hot and neutral. Core grounded to chassis.
If the chassis is grounded to the earth at the AC power source
by the power cord or a separate third wire to the power strip,
how does reversing hot and neutral improve the situation?
This is not to be confused with reversing the polarity of speaker
connections, which is a phase issue (_ _ _'s speakers suck) :-)


It is tobe so confused, if you invert the polarity of all the speakers.



--
Posted via NewsDemon.com - Premium Uncensored Newsgroup Service
-------http://www.NewsDemon.com------
Unlimited Access, Anonymous Accounts, Uncensored Broadband Access

So, if I only invert the polarity of one of the pair of stereo speakers
will I have a vortex of sound? Just kidding :-)

wrote in message
oups.com...

:

wrote in message
oups.com...
Another thing that's even easier than installing a cheater, is to
simply check the polarity of all of your plugs that can be reversed. A
lot of people don't think to do that (especially ignorant old dinosaurs
like Arny Krueger, who don't even believe polarity has any audible
effect). I use music to test for correct polarity. Certain music is
better for checking proper polarity than just anything. Often, I'll
take out my Sheffield Track Record LP (or CD) to test for polarity (or
my Chesky Test CD, which has a trumpet track for polarity testing), by
hearing how the drum is struck. It will sound right (properly struck)
when the plug is correctly inserted, and wrong (inverted) when it
isn't.

Been there done that, no effect.

A freind of mine who was a TAS/Stereophile dogmatist, thought he'd
investigate this "tweak" and yes he did use music. I happened to be at
his
place when he was in the process of trying this out, so I had the
opportunity to let him hear the difference between the "proper "
polorization and the not give a crap version. So without heim knowing
which
was which I wouold switch between them and he would listen. No effect
that
he could determine.

So? You've proven that you and your friend are insensitive
listeners,whereas a million other people can hear polarity.

A million? Your documentation please.
This is a pointless excercise, since there is no way to know how man
polarity inversions there might have been before playing music, then there's
the fact that some amps invert polarity.

Did you
have a point?

Your tweak is pointless.

François Yves Le Gal wrote:

BTW, if an equipment has been designed for 2+1 grounded operation, it's
particularly stupid and dangerous to use a cheater.

No it's not. That Earth ground is only there for safety in the very
unlikely event that the chassis somehow becomes "hot". Really not a
big deal to defeat it with a cheater.

Note: Take the above advise at your own risk. 8)

"dizzy" wrote in message
news
François Yves Le Gal wrote:

BTW, if an equipment has been designed for 2+1 grounded
operation, it's particularly stupid and dangerous to use
a cheater.

No it's not. That Earth ground is only there for safety
in the very unlikely event that the chassis somehow
becomes "hot". Really not a big deal to defeat it with a
cheater.

This would be very ingenuous advice coming from someone posting as "dizzy".
It's dizzy advice.

Note: Take the above advise at your own risk. 8)

IOW do the opposite.

wrote in message
oups.com
:

wrote in message
oups.com...
Another thing that's even easier than installing a
cheater, is to simply check the polarity of all of your
plugs that can be reversed. A lot of people don't think
to do that (especially ignorant old dinosaurs like Arny
Krueger, who don't even believe polarity has any
audible effect). I use music to test for correct
polarity. Certain music is better for checking proper
polarity than just anything. Often, I'll take out my
Sheffield Track Record LP (or CD) to test for polarity
(or my Chesky Test CD, which has a trumpet track for
polarity testing), by hearing how the drum is struck.
It will sound right (properly struck) when the plug is
correctly inserted, and wrong (inverted) when it isn't.

Been there done that, no effect.

Back in the old days, the chassis of many kinds of popular electronic gear
was connected to one of the two power line plugs. The equipment was
marginally safe because it was completely enclosed in an insulating box.
Examples of this included the once-popular 5-tube AC-DC table radio and many
cheap record players. At times this equipment could be sensitive to which
way the power plug was inserted. At times the power cords on this kind of
equipment had special polarized power plugs that could only be easily
inserted one way - the preferred way.

Cheap, poorly designed audio equipment can be sensitive to how the power
cord is inserted. Of course this is a PITA because its just another possible
source of error during system setup. Therefore well-designed audio gear is
insensitive to how the power cord is inserted.

A freind of mine who was a TAS/Stereophile dogmatist,
thought he'd investigate this "tweak" and yes he did use
music. I happened to be at his place when he was in the
process of trying this out, so I had the opportunity to
let him hear the difference between the "proper "
polorization and the not give a crap version. So
without heim knowing which was which I wouold switch
between them and he would listen. No effect that he
could determine.

So? You've proven that you and your friend are insensitive
listeners,whereas a million other people can hear
polarity. Did you have a point?

No, what was proven is that poorly-designed audio gear is sensitive to how
its power cord is inserted, and it has power cords that can be reversed.
Well-designed audio gear is insensitive to how the power cord is inserted,
or it has a power cord that can only be inserted one way - the right way.
Much of the best modern audio gear is designed with both ideas in mind - it
has a power cord that can only be inserted one way, and its performance is
unchanged with reverse-polarity power, perchance the outlet it is plugged
into, is wired with the hot and neutral lines reversed.

"François Yves Le Gal" wrote in message
...
On Sun, 19 Mar 2006 18:32:55 -0500, "Robert Morein"
wrote:

I don't believe stereo equipment is very dangerous.

Neither do I. Fact is that some catch fire and that hundreds of lifes
worldwide are lost because of poor product design/component choice/chassis
build. Adding a cheater plug adds a risk. Why take it?

Also, it should be noted that the incidence of fire has no relationship to
the presence of a chassis ground. You can theorize, but I doubt the
statistics break it out.

Poorly grounded products are the #1 cause of electrocutions.

The issue with that equipment is the
circuit board material, typically epoxy paper, and the considerable use
of
plastics.

The issue is IMO poorly choosen components in a **** poor topology.

100V caps, when the rails are 65 ? The caps that failed are higher voltage
than the electrolytic cans. The spec on the caps is adequate. The defect
rate of the supplier is, of course, another issue.

The topology is not "**** poor". It is a very fine sounding amplifier. Some,
including myself, find the treble slightly edgy, if not matched to the right
speakers. But proper matching is important in any application; it's not
peculiar to the Parasound. With the current speakers, which are Acoustat
2+2's, the sound is impeccable. Maybe not the right amp for metal domes. For
that application, I use amps with MOSFET outputs.


The Parasound which did have bypass
cap ignition is completely encased in metal; the boards are FR-4. The
ignition occurred irrespective of the fact that the Parasound, in fact,
does
not have a cheater plug.

I would say that John Curl went over the bridge in his design, with maybe
some creative bean counters getting the lowest spec'ed parts. Or maybe the
components were defective to begin with, something alas more and more
common
when it comes to boutique amps - even from quality-oriented companies such
as Parasound.

Could be. It did take nine years of use for the two caps to fail, and they
did so within months of each other. Perhaps the "weak sisters" have now been
culled.

"François Yves Le Gal" wrote in message
...
On Mon, 20 Mar 2006 03:11:45 GMT, dizzy wrote:


No it's not. That Earth ground is only there for safety in the very
unlikely event that the chassis somehow becomes "hot". Really not a
big deal to defeat it with a cheater.

What did I say? Anyway, using a proper ground is a necessity nowadays: how
can the mains EMI/RFI filter do it's job w/o a ground?

Obviously, if one has a hum problem, and the cheater plug solves it, this is
not a problem. My solution is to feed all the audio equipment through an EMI
filter, which, located at a central point, is grounded. Therefore, your
point is moot.

Note: Take the above advise at your own risk. 8)

Don't take a chance.
:-)

By all means take the chance. It is infinitesimal compared to the other
hazards of our lives.
Your chances of dying in a car accident are thousands of times greater.

Don't suffer with hum. Try every affordable remedy, and if they don't, use
the plug.
Hum can shorten your life

"François Yves Le Gal" wrote in message
...
On Mon, 20 Mar 2006 14:34:25 -0500, "Robert Morein"
wrote:

My solution is to feed all the audio equipment through an EMI
filter, which, located at a central point, is grounded. Therefore, your
point is moot.

It's not. Local EMI/RFI filters are a must: they curb the hash picked up
by
the cabling system. Using a centralized EMI/RFI filter is quite useless...

Note: Take the above advise at your own risk. 8)

Don't take a chance.
:-)

By all means take the chance.

DON'T. IF EQUIPMENT IS DESIGNED FOR A 2 + 1 MAINS CONNECTION, DEFEATING
THE
GROUNDING SCHE CAN HAVE LETHAL CONSEQUENCES.


THIS IS SHEER BALONEY, WITHOUT A SHRED OF EVIDENCE. IN FACT, THE ACOUSTAT
PRODUCT MANUAL SPECIFICALLY RECOMMENDS THE CHEATER PLUG TWEAK.

(SORRY FOR SCREAMING)
I repeat, more calmly: This is sheer baloney, without a shred of evidence.
In fact, the Acoustat product manual specifically recommends the cheater
plug tweak. Most audio equipment from the 70's and 80's has no 3rd prong,
and is identical in construction to that which does. The electrical codes
have changed, not the reality of the situation.

(Sorry for screaming)

Don't suffer with hum. Try every affordable remedy

Get properly designed components connected to properly grounded mains.
Forget stupid audiophile tweaks.

That could require discarding a lot of equipment. That takes a lot of money.
For a "danger" that is hypothetical.
Please, if anyone out there actually has access to casualty databases with
specific access to the issue, I'm sure Francois and I would be very
interested in hearing. The parameters set is:
1. Audiophile equipment.
2. Home environment, not professional. No bathrooms, standing in puddles,
rain outdoors. Just typical listening environment.
3 Defeated ground via cheater plug.
4. Lethal accident for which forensic investigation concluded that the
defeated ground was the cause.

In professional environments, there have definitely been lethal accidents,
typically involving a performer holding a microphone connected to a
defective phantom power supply, who touches a good ground, or steps in
water, etc. In these cases, none of the six layers of protection I have
described for the cheater plug tweak are in place.

"Arny Krueger" wrote in message
...
"dizzy" wrote in message
news
François Yves Le Gal wrote:

BTW, if an equipment has been designed for 2+1 grounded
operation, it's particularly stupid and dangerous to use
a cheater.

No it's not. That Earth ground is only there for safety
in the very unlikely event that the chassis somehow
becomes "hot". Really not a big deal to defeat it with a
cheater.

This would be very ingenuous advice coming from someone posting as
"dizzy". It's dizzy advice.

Note: Take the above advise at your own risk. 8)

IOW do the opposite.


If you have hum, it's a possible fix for $0.35 and negligible risk.
No one has ever been killed as a result of this tweak.

wrote in message
oups.com...


So, if I only invert the polarity of one of the pair of stereo speakers
will I have a vortex of sound? Just kidding :-)


More like a black hole..



--
Posted via NewsDemon.com - Premium Uncensored Newsgroup Service
-------http://www.NewsDemon.com------
Unlimited Access, Anonymous Accounts, Uncensored Broadband Access