The disappearance of darkness

On Sun, 26 May 2013 21:33:21 +1200, Eric Stevens wrote:



The only driver in a speaker system used at it's resonance point is the woofer.
Woofers typically have crossover coils in series with them. For a typical xover
around 500hz, the value of the coil would be in the neighborhood of 2 to 3
millihenrys. The idea that adding a small value, measured in microhenrys, of
inductance from the speaker cable, would compromise the sound, or even affect
the sound in any audible way, is just stupid. What it would do, if anything, is
create a low pass filter far above the audible range, on the entire system. It
would not affect the woofer.

So the first thing you do when responding to my question is postulate
circumstances when it is irrlevant. Brilliant.

This is what you said:

Now calculate the effect a change in cable reactance on the damping of
a speaker at it's resonant frequency.

Irrelevent? **** YOU'RE STUPID!!

The other speakers in the system typically have series capacitors. They would
cancel out any small added series inductance and merely create a slightly
different filter frequency. Not audible.

Modern amplifiers are designed to drive highly reactive loads. "Microhenrys" is
not 'highly reactive'. The first amplifier I built in the seventies ran the
speakers through 4000uf of capacitance.

Whatever you built in the 70s would not have been what is known as
'high fidelity'. Whatever you were doing would not have made much
difference.

Totally missed the point you ****ING ASSHOLE!

F U C K O F F !!


- P L O N K -

On Sun, 26 May 2013 17:32:55 -0400, Alan Browne
wrote:

On 2013.05.24 20:48 , Eric Stevens wrote:
On Fri, 24 May 2013 16:10:07 -0400, Alan Browne
wrote:

On 2013.05.24 00:30 , Eric Stevens wrote:
On Thu, 23 May 2013 21:56:27 -0400, wrote:

On Thu, 23 May 2013 15:26:32 +1200, Eric Stevens wrote:

On Wed, 22 May 2013 21:19:48 -0400, wrote:

On Wed, 22 May 2013 18:34:32 -0400, nospam wrote:

Next time you're near a hydro tower, listen to the hum of the wires and tower...

What is a 'hydro tower'?

Wires hum without electricity. It's just the wind.

Right, a 60hz or 120hz or 180hz wind...

Listen kid, get back to your day care center before they put out an Amber Alert
on you!

I'm not saying that you can't hear corona losses.

I'm saying you can get vibrations induced from vortex shedding of the
wind. http://en.wikipedia.org/wiki/Vortex_shedding "This vibration is
the cause of the "singing" of overhead power line wires in a wind, ...
"

The hum is most audible in dead still air. No wind needed.

Dry air - Corona discharge - no hum - more like white noise

Humid air - hum @ 120 Hz (100Hz if 50 Hz base)

See my other post.

And if really fond of wikipedia, see the article:
https://en.wikipedia.org/wiki/Mains_hum

"Around high-voltage power lines, hum _may_ be produced by corona
discharge." (empasis added).

But I'd add that the core of transmission lines is steel. And that will
move v. the magnetic field - it hums.

It doesn't have to be steel to interact with a magnetic field. It only
has to be a conductor carrying electricity.

Again there are two forms.

Corona discharge has a 'crackling' sound. (dry air).

Magnetic effect has a humming noise. (humid air)

'Two forms' of humming I presume.

There is a third: vortex shedding induced by wind.

What is the source of the magnetic field in your "Magnetic Effect"
with which the current interacts and why is it only present when the
air is humid?
--

Regards,

Eric Stevens

On Sun, 26 May 2013 21:32:15 -0400, wrote:

On Sun, 26 May 2013 21:33:21 +1200, Eric Stevens wrote:



The only driver in a speaker system used at it's resonance point is the woofer.
Woofers typically have crossover coils in series with them. For a typical xover
around 500hz, the value of the coil would be in the neighborhood of 2 to 3
millihenrys. The idea that adding a small value, measured in microhenrys, of
inductance from the speaker cable, would compromise the sound, or even affect
the sound in any audible way, is just stupid. What it would do, if anything, is
create a low pass filter far above the audible range, on the entire system. It
would not affect the woofer.

So the first thing you do when responding to my question is postulate
circumstances when it is irrlevant. Brilliant.

This is what you said:

Now calculate the effect a change in cable reactance on the damping of
a speaker at it's resonant frequency.

Irrelevent? **** YOU'RE STUPID!!

The other speakers in the system typically have series capacitors. They would
cancel out any small added series inductance and merely create a slightly
different filter frequency. Not audible.

Modern amplifiers are designed to drive highly reactive loads. "Microhenrys" is
not 'highly reactive'. The first amplifier I built in the seventies ran the
speakers through 4000uf of capacitance.

Whatever you built in the 70s would not have been what is known as
'high fidelity'. Whatever you were doing would not have made much
difference.

Totally missed the point you ****ING ASSHOLE!

F U C K O F F !!


- P L O N K -

You somehow overlooked this bit:

There are obviously some things you don't understand. And never will
by the look of it. Hint - consider the effects on the feedback loop.
--

Regards,

Eric Stevens

"Chris Malcolm" wrote in message
...
That is exactly my point -- thet you can be misled by blidly following
obvious "evidence-based" scientific experiments if you haven't taken
the care to make explicit the underlying assumptions and made sure
that the implied models hold.

An obvious contradiction. An experiment is *not* "evidence based" if it
relies on unproven assumptions and models.
That's how psuedo science works of course.

Trevor.

On 2013.05.26 23:33 , Eric Stevens wrote:
On Sun, 26 May 2013 17:32:55 -0400, Alan Browne
wrote:

On 2013.05.24 20:48 , Eric Stevens wrote:
On Fri, 24 May 2013 16:10:07 -0400, Alan Browne
wrote:

On 2013.05.24 00:30 , Eric Stevens wrote:
On Thu, 23 May 2013 21:56:27 -0400, wrote:

On Thu, 23 May 2013 15:26:32 +1200, Eric Stevens wrote:

On Wed, 22 May 2013 21:19:48 -0400, wrote:

On Wed, 22 May 2013 18:34:32 -0400, nospam wrote:

Next time you're near a hydro tower, listen to the hum of the wires and tower...

What is a 'hydro tower'?

Wires hum without electricity. It's just the wind.

Right, a 60hz or 120hz or 180hz wind...

Listen kid, get back to your day care center before they put out an Amber Alert
on you!

I'm not saying that you can't hear corona losses.

I'm saying you can get vibrations induced from vortex shedding of the
wind. http://en.wikipedia.org/wiki/Vortex_shedding "This vibration is
the cause of the "singing" of overhead power line wires in a wind, ...
"

The hum is most audible in dead still air. No wind needed.

Dry air - Corona discharge - no hum - more like white noise

Humid air - hum @ 120 Hz (100Hz if 50 Hz base)

See my other post.

And if really fond of wikipedia, see the article:
https://en.wikipedia.org/wiki/Mains_hum

"Around high-voltage power lines, hum _may_ be produced by corona
discharge." (empasis added).

But I'd add that the core of transmission lines is steel. And that will
move v. the magnetic field - it hums.

It doesn't have to be steel to interact with a magnetic field. It only
has to be a conductor carrying electricity.

Again there are two forms.

Corona discharge has a 'crackling' sound. (dry air).

Magnetic effect has a humming noise. (humid air)

'Two forms' of humming I presume.

No. The crackling sound is not all like a hum.

There is a third: vortex shedding induced by wind.

We were addressing the electrical form of noise - most often heard when
the air is still. If it makes you feel warm and fuzzy nobody denies
that wind can make wires hum.

What is the source of the magnetic field in your "Magnetic Effect"
with which the current interacts and why is it only present when the
air is humid?

When the air is humid there is something to make noise (water droplets
moving around). The magnetic field is generally present at all times.
Think about it. Let your compass guide you.


--
"A Canadian is someone who knows how to have sex in a canoe."
-Pierre Berton

On Mon, 27 May 2013 16:48:50 -0400, Alan Browne
wrote:

On 2013.05.26 23:33 , Eric Stevens wrote:
On Sun, 26 May 2013 17:32:55 -0400, Alan Browne
wrote:

On 2013.05.24 20:48 , Eric Stevens wrote:
On Fri, 24 May 2013 16:10:07 -0400, Alan Browne
wrote:

On 2013.05.24 00:30 , Eric Stevens wrote:
On Thu, 23 May 2013 21:56:27 -0400, wrote:

On Thu, 23 May 2013 15:26:32 +1200, Eric Stevens wrote:

On Wed, 22 May 2013 21:19:48 -0400, wrote:

On Wed, 22 May 2013 18:34:32 -0400, nospam wrote:

Next time you're near a hydro tower, listen to the hum of the wires and tower...

What is a 'hydro tower'?

Wires hum without electricity. It's just the wind.

Right, a 60hz or 120hz or 180hz wind...

Listen kid, get back to your day care center before they put out an Amber Alert
on you!

I'm not saying that you can't hear corona losses.

I'm saying you can get vibrations induced from vortex shedding of the
wind. http://en.wikipedia.org/wiki/Vortex_shedding "This vibration is
the cause of the "singing" of overhead power line wires in a wind, ...
"

The hum is most audible in dead still air. No wind needed.

Dry air - Corona discharge - no hum - more like white noise

Humid air - hum @ 120 Hz (100Hz if 50 Hz base)

See my other post.

And if really fond of wikipedia, see the article:
https://en.wikipedia.org/wiki/Mains_hum

"Around high-voltage power lines, hum _may_ be produced by corona
discharge." (empasis added).

But I'd add that the core of transmission lines is steel. And that will
move v. the magnetic field - it hums.

It doesn't have to be steel to interact with a magnetic field. It only
has to be a conductor carrying electricity.

Again there are two forms.

Corona discharge has a 'crackling' sound. (dry air).

Magnetic effect has a humming noise. (humid air)

'Two forms' of humming I presume.

No. The crackling sound is not all like a hum.

There is a third: vortex shedding induced by wind.

We were addressing the electrical form of noise - most often heard when
the air is still. If it makes you feel warm and fuzzy nobody denies
that wind can make wires hum.

This all started when BobF wrote:

Next time you're near a hydro tower, listen to the hum of the wires and tower...

.... and I replied

What is a 'hydro tower'?

Wires hum without electricity. It's just the wind.

So we weren't just addressing the electrical form of noise. We were
discussing the humming of power lines.


What is the source of the magnetic field in your "Magnetic Effect"
with which the current interacts and why is it only present when the
air is humid?

When the air is humid there is something to make noise (water droplets
moving around). The magnetic field is generally present at all times.
Think about it. Let your compass guide you.

I thought you would be relying on the earth's magnetic field. This
shouldn't be affected by humidity. Nor should the water droplets be
affected by magnetism. They do however produce a leakage path which
reduces the dielectric strength of the air.
--

Regards,

Eric Stevens

In rec.photo.digital.slr-systems Trevor wrote:

"Chris Malcolm" wrote in message
...
That is exactly my point -- thet you can be misled by blidly following
obvious "evidence-based" scientific experiments if you haven't taken
the care to make explicit the underlying assumptions and made sure
that the implied models hold.

An obvious contradiction.

The problem is that this is only obvious at first glance.

An experiment is *not* "evidence based" if it
relies on unproven assumptions and models.
That's how psuedo science works of course.

In that case a great deal of public medical policy is pseudo
science.

It's also well known to be the case that in periods of what Kuhn
called "normal science" (in "The Structure of Scientific Revolutions")
the assumptions and models are usually not made explicit. Plus the
assumptions and models underlying a specific scientific paradigm are
only provisionally proved by the ongoing success of the paradigm. As
Popper pointed out what is often taken to have been scientifically
proved is in fact really only so far not disproved.

--
Chris Malcolm

In article ,
says...

In rec.photo.digital.slr-systems Trevor wrote:

"Chris Malcolm" wrote in message
...
That is exactly my point -- thet you can be misled by blidly following
obvious "evidence-based" scientific experiments if you haven't taken
the care to make explicit the underlying assumptions and made sure
that the implied models hold.

An obvious contradiction.

The problem is that this is only obvious at first glance.

An experiment is *not* "evidence based" if it
relies on unproven assumptions and models.
That's how psuedo science works of course.

In that case a great deal of public medical policy is pseudo
science.

It's also well known to be the case that in periods of what Kuhn
called "normal science" (in "The Structure of Scientific Revolutions")
the assumptions and models are usually not made explicit. Plus the
assumptions and models underlying a specific scientific paradigm are
only provisionally proved by the ongoing success of the paradigm. As
Popper pointed out what is often taken to have been scientifically
proved is in fact really only so far not disproved.

Would you be kind enough to provide an example of an experiment in which
"assumptions and models" affect the outcome?

J. Clarke wrote:

Would you be kind enough to provide an example of an experiment in which
"assumptions and models" affect the outcome?

Experiment as in "the measured raw results" or as in "the
results after evaluating the measurements"?

-Wolfgang

On Tue, 28 May 2013 02:59:43 -0700 (PDT), Whisky-dave
wrote:

On Thursday, May 23, 2013 2:19:48 AM UTC+1, wrote:
On Wed, 22 May 2013 18:34:32 -0400, nospam wrote:



In article , Eric Stevens

wrote:



They don't listen to electricity.



of course they do. electricity is what moves the speaker coil.



No what moves the coils is the effect of magnatism that does that.



because there's electricity flowing in a coil.



I'd call it current but each to his own.



technically it's current, but it doesn't change anything.



It changes the magnetic field of the coil.



that's the whole point, and calling it electricity or current doesn't

change that.



if it wasn't for electricity, there would be no sound.



if it weren't for the cone compressing the air etc.. they'd be no

sound.



because electricity is causing it to move.



No, magnatism is doing that 'electricity' runs through many wire's in

cables

and they don't all make sounds.



so what?



Electricity doesn't make sound. (Can you plug wires into your head and

listen to music?)



shut off the electricity to your house and let us know how much sound

you get from your sound system.



if there was no electricity there would be no sound. period.



Hey nospam, I'd give up if I were you... you're wasting your time with people

who insist on proving that they have no technical education what so ever!



Any flow of electric current produces magnetism. Alternating current in the

audio range can induce movement in anything conductive near the current carrier,

including the carrier itself. Such movement creates sound by definition. (object

vibrating at an audio frequency)



Next time you're near a hydro tower, listen to the hum of the wires and tower...

Why does it have to be a hydro tower, I've heard humming from a substantion and the humming is caused by the transformers which are made out of wire.

The humming of transformers is primarily caused by magnetostriction -
the changes in the dimensions of the iron core elements with each
cycle of magnetisation.

But a lot of the so called hum from over head cables is actualy electrical discharge.

--

Regards,

Eric Stevens