Power Cords
 

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


While I can appreciate a mains cable ain't going to make
any difference with a clean power supply, to what extent
do these noise reducing mains cables with their ferrite
rings and platted cables reduce an interference that may
be inherent in the supply?

The biggest EMI filter in most power supplies is the power transformer. If
its optimized for efficiency at 60 Hz, its likely to be a good rejector of
higher frequencies.



I beg to differ. Frequencies above 50/60Hz can find their way across/through
that transformer, even when an electrostatic screen is present. It's a very
complex subject.

Any decent amplifier will have good rejection of any crap likely to be
picked up or conducted by ALL the cables going to it (speakers, inputs and
mains).

Graham Holloway
www.accuphon.co.uk

Power Cords
 

In article ,
Arny Krueger wrote:
Most kettles are relatively low-powered compared to the
appliances that are heavy-hitters.

Not in the UK with our 230 volt supply. They can be up to 3 kW and boil
very much faster than using a cooker, so are near universal.

In the average UK house, the only devices which are likely to take more
current - and therefore be 'hard wired' - are electric showers (nasty
things) stand alone cookers, and some water heaters, usually just a
standby. Most UK homes have gas, and this is used for space and water
heating.

--
*I don't work here. I'm a consultant

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

Power Cords
 

In article . com,
David
Lodge wrote:
Jim Lesurf wrote:
FWIW my experience is that some items do produce audible 'clicks' at
times which are mains injected. Reason follows from the above: PSU and
rail rejection not adequate. This can be dealt with by using a mains
filter, not an expensive mains cable. Alternatively, change the item
for something else that has a better PSU and/or amp stages with better
rail rejection.

That all make sense (both what I quoted above and what I didn't), so is
it fair to say: - mains filtering devices can provide a degree of noise
reduction, but whether you'll hear a difference or benefit from it
depends on the level of noise in the first place, and the extent to
which your amp (or source component) filters out the noise anyway

Yes. If you find whilst listening to your audio system that you can hear
occasional 'clicks' which seem to come from things like light switches,
fridge motors, etc, then a mains filter may help eliminate these. However
this isn't much to do with fancy mains cables, or the more mysterious and
subtle changes which some sellers of cables describe. Just about having a
PSU/amp that doesn't let mains-carried interference get onto the output of
the amp..

- Good main cables themselves are likely to provide a benefit only if
they replace a cable which is difficient in delivering the required
power. Once its sufficient (as I suspect most standard cables are),
there's no additional benefit to be gained by replacing them with
"better" cables.

That is my exprience. It is also my understanding of the relevant physics,
etc. My main pun concerns with mains cables are safety, and that they
have no basic flaws/problems like non-ohmic (dirty) contacts. Nothing
fancy.

Slainte,

Jim

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

Power Cords
 

In article , Mike Gilmour
writes

"Dave Plowman (News)" wrote in message
...
In article ,
Luke Siemaszko wrote:
So how does a kettle get on then pulling the power it takes?, and I've
never had a problem with an actual kettle connector....

Kettle draws loads of power
some is wasted in voltage drop over crap connector
connector gets slightly warm
you don't notice
life continues

there aren't (as far as I know) hordes of kettle enthusiats eager to
squeeze every last drop of performance from their kettles. Amplfifiers,
thoough, operate in a different environemnt to kettles.....

A kettle draws continuous power at around 2 kW. Domestic amps don't draw
anywhere near at *peak* 2kW. That's 2000 watts. And then they convert that
AC to DC and use large reservoir capacitors. Of course you might have a
2000 watt amplifier but I somehow doubt it.

--
*Everyone has a photographic memory. Some just don't have film.

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

Don't doubt. Just a quote from my ss NRG manual Model A201S:
Power consumption: Maximum for each respective load
Idle (No Load) 1.3kW
8 Ohm 1.3kW
4 Ohm 1.65kW
2 Ohm 3.3kW
1 Ohm 6.4kW
The actual values will typically be lower with 'normal' music, though I
could have been a deaf headbanger with a pair of 1 ohm Apogee Scintilla ;-)
I'm sure some of the larger Krells spec much the same. Its fun/agonizing
watching the digits on the consumer unit whizz around on something like the
S/Saens Organ symphony. Thats exactly why the supply cable is hard wired
rather than trusting to an iec connector.

-=Mike=-



Jezzzz...sus

How much power does the original organ take?
--
Tony Sayer

Power Cords
 

In article , Mike Gilmour
wrote:

"Dave Plowman (News)" wrote in message
...

Of course you might have a 2000 watt amplifier but I somehow doubt it.



Don't doubt. Just a quote from my ss NRG manual Model A201S: Power
consumption: Maximum for each respective load Idle (No Load) 1.3kW 8 Ohm
1.3kW 4 Ohm 1.65kW 2 Ohm 3.3kW 1 Ohm 6.4kW

The actual values will typically be lower with 'normal' music,

Indeed. Probably with medium-term average values not much more than the 'no
load' value.

though I could have been a deaf headbanger with a pair of 1 ohm Apogee
Scintilla ;-)

I suspect that the speakers would have failed long before you went deaf if
the medium-term power level drawn from the wall was anything like 6kW.
Hard to know if you would be fleeing the room to get away from the noise,
or the flames... :-)

I'm sure some of the larger Krells spec much the same. Its
fun/agonizing watching the digits on the consumer unit whizz around on
something like the S/Saens Organ symphony. Thats exactly why the supply
cable is hard wired rather than trusting to an iec connector.

Pleased to say that I enjoy such music without having such concerns. :-)

Slainte,

Jim

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

Power Cords
 

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

In article
om,
David Lodge wrote:


Is there not another angle to look at (says he throwing
fuel on the cynical fire...) and that is when the mains
power supply is noisey.

This is why amplifier designers tend to pay attention to
ensuring the amp has a decent PSU, and has some level of
inherent noise rejection. They also live in the real
world. Indeed, the mains supply in many factories or labs
can be even worse than domestic mains in terms of the
interference added to the basic mains waveforms.

While I can appreciate a mains cable ain't going to make
any difference with a clean power supply, to what extent
do these noise reducing mains cables with their ferrite
rings and platted cables reduce an interference that may
be inherent in the supply?

The biggest EMI filter in most power supplies is the power transformer. If
its optimized for efficiency at 60 Hz, its likely to be a good rejector of
higher frequencies.

**You'd be wrong. Particularly in the case of most toroidal types. An
efficient, close coupled power transformer can exhibit an excellent HF
response.


--
Trevor Wilson
www.rageaudio.com.au

Power Cords
 

Arny Krueger wrote:

Most kettles are relatively low-powered compared to the
appliances that are heavy-hitters.

In the US self-heated kettles are far from the largest
single users of power. Electric space heaters are near or at
the top.

Have you ever been to the UK?

My kettle is 3.2kw. My shower is 10.5 Kw. Heating here is done mostly with
gas (as in natural gas, not petrol) or oil (kerosene / diesel)

If the US wasted less power in electric space heaters maybe the world would
be a better place?


--
Just remember that you're standing on a planet that's evolving / And
revolving at 900 miles an hour / That's orbiting at 19 miles a second,
so it's reckoned, / A sun that is the source of all our power. / The
sun and you and me and all the stars that we can see, / Are moving at a
million miles a day / In an outer spiral arm, at 40,000 miles an hour,
/ Of the galaxy we call the Milky Way.

Power Cords
 

"Tim S Kemp" wrote in message
. ..
Arny Krueger wrote:

Most kettles are relatively low-powered compared to the
appliances that are heavy-hitters.

In the US self-heated kettles are far from the largest
single users of power. Electric space heaters are near or at
the top.

Have you ever been to the UK?

My kettle is 3.2kw. My shower is 10.5 Kw. Heating here is done mostly with
gas (as in natural gas, not petrol) or oil (kerosene / diesel)



While it lasts (ie remains 'economically gettable').... ;-)



If the US wasted less power in electric space heaters maybe the world
would be a better place?


Did that get a specific mention at the Kyoto Summit...??



--
Just remember that you're standing on a planet that's evolving / And
revolving at 900 miles an hour / That's orbiting at 19 miles a second,
so it's reckoned, / A sun that is the source of all our power. / The
sun and you and me and all the stars that we can see, / Are moving at a
million miles a day / In an outer spiral arm, at 40,000 miles an hour,
/ Of the galaxy we call the Milky Way.


Not forgetting the galaxies are flying away (mostly, I gather) from each
other at a fair rate of knots also...

Power Cords
 

In article ,
Keith G wrote:
My kettle is 3.2kw. My shower is 10.5 Kw. Heating here is done mostly
with gas (as in natural gas, not petrol) or oil (kerosene / diesel)

While it lasts (ie remains 'economically gettable').... ;-)

Then we'll have a problem with electricity too since the majority is
generated from gas.

--
*If you must choose between two evils, pick the one you've never tried before

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

Power Cords
 

"Dave Plowman (News)" wrote in message
...
In article ,
Keith G wrote:
My kettle is 3.2kw. My shower is 10.5 Kw. Heating here is done mostly
with gas (as in natural gas, not petrol) or oil (kerosene / diesel)

While it lasts (ie remains 'economically gettable').... ;-)

Then we'll have a problem with electricity too since the majority is
generated from gas.



I reckon natural gas supplies will be reserved for industrial processes in
the not-too-distant future and domestic supplies will be phased out and that
the future for electricity generation on a massive scale lies in the nucular
domain with any amount of harebrained schemes to supplement it on a domestic
level....

FWIW....