tweeter speaker wire - Page 6 - AVS Forum
Forum Jump: 
Reply
 
Thread Tools
post #151 of 170 Old 12-23-2012, 12:02 AM - Thread Starter
Member
 
billnln's Avatar
 
Join Date: Jun 2011
Posts: 54
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I think there are good,---- I just can't do them because it takes me too long to identify an improvement. (ala your post)
It would take professional listeners who have already heard the differences
thereby making the results suspect.
billnln is offline  
Sponsored Links
Advertisement
 
post #152 of 170 Old 12-23-2012, 04:02 AM
AVS Addicted Member
 
arnyk's Avatar
 
Join Date: Oct 2002
Location: Grosse Pointe Woods, MI
Posts: 14,382
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 753 Post(s)
Liked: 1167
Quote:
Originally Posted by JHAz View Post

IMO, absent trable rolloff caused by high capacitance, the only time a cable should have an audible effect is if it is undersized, adding significantly to the effective output impedance of the amplifier.

You seem to have missed the third potential source of audible coloration in speaker wire, being inductance. And the fourth being skin effect.

As practical matters it is very rare for any of the 4 possible sources of treble loss to actually cause an audible difference:

(1) Capacitance
(2) Inductance
(3) DC resistance
(4) Skin effect of it you will high frequency AC resistance

However, all of them can have measurable effects and under extreme conditions, any might have an audible effect.

And that's only going to make a difference if the amp had a highish output impedance already and the speakers happen to have a difficult to drive (i.e. drops low) impedance.
[/quote]

The output impedance of the amplifier need not be high for speaker wire with high resistance to cause an audible effect. If fine enough and long enough the wire can cause an audible effect all by itself.

For example, 30 gauge wire (hair fine wire) has a resistance of about 0.1 ohm per foot. A 5 foot 30 gauge speaker cable has 1 ohm resistance.

This is the impedance curve of a fairly ordinary reasonably-well designed speaker:



The speaker has a 14 ohm impedance (all resistive) at about 40 Hz. That causes only a 0.7 dB loss. Above about 200 Hz the speaker has an average impedance of about 5 ohms which leads to an loss that is about 1.5 dB. The difference in loss between these two areas leads to a clearly measurable and possibly audible (but probably not) response difference.

Poorly-designed speakers can cause greater response differences. Note that the example is very extreme - nobody in their right mind would use 30 gauge speaker cable. I think the thinnest wire ever sold for the use with speakers is 24 gauge, which has only abouta quarter as much resistance. Of course, if you run a 40 foot 24 gauge speaker cable then things are about twice as bad as my example.
arnyk is offline  
post #153 of 170 Old 12-23-2012, 05:32 PM - Thread Starter
Member
 
billnln's Avatar
 
Join Date: Jun 2011
Posts: 54
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
arnyk,--- do you have any thoughts about time distortions caused by wire?
What I hear is better openness to the room where the music was recorded
with some cables.
billnln is offline  
post #154 of 170 Old 12-24-2012, 04:34 AM
AVS Addicted Member
 
arnyk's Avatar
 
Join Date: Oct 2002
Location: Grosse Pointe Woods, MI
Posts: 14,382
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 753 Post(s)
Liked: 1167
Quote:
Originally Posted by billnln View Post

arnyk,--- do you have any thoughts about time distortions caused by wire?

They are generally tiny. They are miniscule compared to the time distortions that happen naturally during recording with microphones and playback via speakers.
Quote:
What I hear is better openness to the room where the music was recorded
with some cables.

In my experience differences like that go away as you tighten up your listening test methodologies.
arnyk is offline  
post #155 of 170 Old 12-24-2012, 12:02 PM - Thread Starter
Member
 
billnln's Avatar
 
Join Date: Jun 2011
Posts: 54
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Yes I agree that compared to the whole process and especially the in home setup--- the timing improvements are small with cables. The thing I am most sensitive to ----both in music and setup is something to do with timing. I might hear differences in tonal qualities ----but I'm not sure what I prefer.
As I said earlier ---the Keith Johnson test disk that runs some kind of demagnetizing sweeps seem to help.
What do you think of unnecessarily large awg as it relates to timing.
My cables go from my 25 watt amp to a speaker with a built in bass/mid amp.
Except for acting like a pre amp for the bass/mid amp----I am only driving the tweeter.
billnln is offline  
post #156 of 170 Old 12-24-2012, 08:23 PM
Senior Member
 
kraut's Avatar
 
Join Date: Sep 2012
Posts: 379
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 60
Quote:
the timing improvements are small with cables.


like as in " only existing in my imagination?"

What is this timing **** about anyway? We are talking signals 20Hz to 20Khz, not in the MHz region. Get your scale correct.
kraut is offline  
post #157 of 170 Old 12-24-2012, 09:33 PM
AVS Special Member
 
krabapple's Avatar
 
Join Date: Apr 2003
Location: in a state bordered by Kentucky and Maine
Posts: 5,304
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 130 Post(s)
Liked: 184
Quote:
Originally Posted by billnln View Post

Yes I agree that compared to the whole process and especially the in home setup--- the timing improvements are small with cables. The thing I am most sensitive to ----both in music and setup is something to do with timing. I might hear differences in tonal qualities ----but I'm not sure what I prefer.
As I said earlier ---the Keith Johnson test disk that runs some kind of demagnetizing sweeps seem to help.
What do you think of unnecessarily large awg as it relates to timing.
My cables go from my 25 watt amp to a speaker with a built in bass/mid amp.
Except for acting like a pre amp for the bass/mid amp----I am only driving the tweeter.

The guy who used to wrap magic paper around his cables was funnier than this. Please try harder.
krabapple is offline  
post #158 of 170 Old 12-24-2012, 09:49 PM
 
SAM64's Avatar
 
Join Date: Apr 2011
Posts: 1,592
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 19 Post(s)
Liked: 74
Quote:
the Keith Johnson test disk that runs some kind of demagnetizing sweeps seem to help.

"some kind of" BS
SAM64 is offline  
post #159 of 170 Old 12-25-2012, 11:01 AM - Thread Starter
Member
 
billnln's Avatar
 
Join Date: Jun 2011
Posts: 54
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Is it possible to contain a signal within a copper wire?
Coax's signal "travels" from the center of the core and in the space up to the shield. Right?
billnln is offline  
post #160 of 170 Old 12-25-2012, 11:40 AM
Senior Member
 
kraut's Avatar
 
Join Date: Sep 2012
Posts: 379
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 60
http://www.st-andrews.ac.uk/~www_pa/Scots_Guide/audio/skineffect/page1.html
http://www.st-andrews.ac.uk/~www_pa/Scots_Guide/audio/skineffect/page2.html...and continue
http://www.st-andrews.ac.uk/~www_pa/Scots_Guide/audio/part7/page1.html ....and continue
http://www.st-andrews.ac.uk/~www_pa/Scots_Guide/audio/part7/page3.html :
Quote:
The Skin Effect arises when EM waves are incident upon, or are guided by, conducting surfaces. The E-fields set up currents in the surface and hence the field only penetrates for a finite distance. This in turn means that the currents only exist near the surface. In practice, in a ‘thick’ conductor the current level falls exponentially with the depth below the metal surface. The result is that the currents on conductors associated with a guided field only make use of a finite metal thickness. Hence the resistance experienced by the currents (which leads to dissipation losses) is influenced by this thickness as well as the material’s resistivity. The magnitude of the current falls exponentially with a 1/e scale depth given – for good conductors – by the approximate expression

equation

The significant point is that this thickness depends upon the signal frequency as well as the conductivity.

As you might gather from this website, cables and their effect have little to do with what your opinion is, cable technology has to do with physics and math.
The only question is are any of the differences in the usual home environment and at the transmitted frequencies of any audible consequences - and no one in any attempt of a rigorous test has been able to show beyond chance that differences are discernible.
kraut is offline  
post #161 of 170 Old 12-25-2012, 11:43 AM
AVS Special Member
 
Glimmie's Avatar
 
Join Date: Sep 2000
Location: Los Angeles, CA
Posts: 7,978
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 168 Post(s)
Liked: 227
Quote:
Originally Posted by billnln View Post

Is it possible to contain a signal within a copper wire?
Coax's signal "travels" from the center of the core and in the space up to the shield. Right?

Well yes, for a time at least. In audio it's a ridiculous amount of cable. But for video, even standard NTSC video from your old VCR can be easily delayed by cable length. In fact your old NTSC TV had a delay line in the luminance path to "hold back" the B&W portion of the video signal while the chroma information was being demodulated. Every NTSC color TV ever made has a luminance delay line. The actual color demodulator circuits delay were in the single digit nanoseconds but the the band pass filters in the chroma channels were in the hundreds of nanoseconds. The filters had series inductors which is basically a long piece of wire, The delay line was also a long length of wire sometimes tapped along the way with capacitors. If this were not done you would see a noticeable B&W fringe on the edge of any colorful transition in the image*. In broadcast systems multiple video feeds into a switcher had to be timed as well. In the old days that was accomplished by making cable lengths equal. I understand Radar systems has similar timing requirements.

In another example look at a modern PC motherboard. You will no doubt see some copper traces that look like scope waveforms. Well this is physical length being added to that trace or wire to keep the signal it carries in time with another. Now, note I said modern PC motherboard. You won't see this on an old 8mhz PC. Why? Because those old PC's didn't have high enough buss clock frequencies to make timed wiring traces under a foot in length a factor. Today's PCs with buss speeds in the hundreds of megahertz require timed wiring even for a few inches in length.

So there you have it. Even though the speed of electrical signals travel at 66% light speed in a wire, it can be too long a time even in consumer electronics.

But again at audio frequencies the electrical delay introduced by wiring length is insignificant. It's all relative to the frequency of the signal.

*not to be confused with a convergence error. That's a different and very common CRT problem from the RGB beams not being in perfect registration.

Glimmie's HT Page
Being redone - comming soon!

Glimmie is offline  
post #162 of 170 Old 12-25-2012, 11:46 PM - Thread Starter
Member
 
billnln's Avatar
 
Join Date: Jun 2011
Posts: 54
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Thank you for answers and patience.
I know you have all said the time anomaly's are insignificant at audio frequencies, but I am still interested.
Can a wire be coated with something and not have any skin effect and the
signal stay in the copper wire?
When I imagine the coax ----the signal is "traveling " though many different
environments
copper, skin, dielectric, passed the return skin field.
A lot of possibilities for small time problems.
I thought it might be possible to keep it simple with just copper.
billnln is offline  
post #163 of 170 Old 12-26-2012, 04:20 AM
AVS Addicted Member
 
arnyk's Avatar
 
Join Date: Oct 2002
Location: Grosse Pointe Woods, MI
Posts: 14,382
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 753 Post(s)
Liked: 1167
Quote:
Originally Posted by billnln View Post

Thank you for answers and patience.
I know you have all said the time anomaly's are insignificant at audio frequencies, but I am still interested.
Can a wire be coated with something and not have any skin effect and the signal stay in the copper wire?

No. The concentration of the signal in the outer layer of the wire is due to magnetic fields. But to re-iterate this is not an audible issue for speaker cables or interconnects carrying audio signals.

Quote:
When I imagine the coax ----the signal is "traveling " though many different
environments
copper, skin, dielectric, passed the return skin field.

Don't overwork your imagination. The mistaken idea that audio signals might get scrambled in time within the same wire has been around for a long time and it is a fantasy.
Quote:
A lot of possibilities for small time problems.

The operative word being small as in very small, infinitesimal, irrelevant, inaudible.
Quote:
I thought it might be possible to keep it simple with just copper.

Doesn't matter with regular analog audio signals.
arnyk is offline  
post #164 of 170 Old 12-26-2012, 05:51 AM
AVS Special Member
 
jneutron's Avatar
 
Join Date: Mar 2007
Posts: 1,879
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 17
Quote:
Originally Posted by billnln View Post

Doesn't that fall well within the 1usec range?
Unless I misunderstand ---it's in the thousandth?
1 milli = 1 /1000, one thousanth. (1 mSec)
1 micro = 1/1000000, one millionth. (1 uSec)
1 nano = 1/000000000, one billionth (1 nSec

The prop velocity of a signal along a cable is about 1 nano second per foot.
We can localize at about the 1 uSec range.
The prop velocity of sound is approximately 1 millisecond per foot.
Quote:
Originally Posted by arnyk View Post

No. The concentration of the signal in the outer layer of the wire is due to magnetic fields.
In a little more detail...

There is a magnetic field which is within the wire caused by the current that travels in the wire. As the frequency increases, the time varying magnetic field within the wire will create a toroidal current in the metal of the wire. This current will be opposite the wire current at the center of the wire, and in the same direction at the surface of the wire. As a result, the current will be less in the center, more at the surface. As the frequency increases, this effect becomes greater.

This effect also includes the current of the other conductor in the circuit...but instead of calling it skin effect, it is called proximity effect. The physics is the same however. The current is always trying to take the least reactive path,
jn

Some discuss because they can. Others attack because they cannot. (unknown attribution)
A good man knows his own limitations...(Dirty Harry)
Lead, follow....or get out of the way..
jneutron is offline  
post #165 of 170 Old 12-27-2012, 03:36 AM
Member
 
stereo2.0's Avatar
 
Join Date: Jul 2006
Location: Port Coquitlam, BC
Posts: 177
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 20
Quote:
Originally Posted by billnln View Post

...I have some pretty good quality cables now and can hear a difference between them and lamp cord, but I need longer cables and want to do as good of a job as I can afford.

You might be interested in reading an article written about two decades ago about the effects of using different speaker cables at http://www.theaudiocritic.com/back_issues/The_Audio_Critic_16_r.pdf starting at page 51. (pdf page 39)
He does mention using a coaxial cable near the end of the article, but you'll probably enjoy it more if you read it from start to finish because it's always more interesting if you learn something new along the way.
(Note: his examples are for longer lengths of wire than you are considering, so all the effects he's noted would be reduced in your application)

A word of warning, this may be hard to read because:
a) he's not always systematic when going from one cable to the next. (Ex: doesn't go from lowest resistance to highest)
b) his writing style may come off as being somewhat angry/arrogant because he has absolutely no patience for people who form subjective opinions about the way things sound in audio.

If you can read it without being offended then you should pick up enough facts to form your own opinions on why speaker cables sound the way they do.
(you might even choose to change your viewpoint on some long held beliefs)
stereo2.0 is offline  
post #166 of 170 Old 12-27-2012, 05:55 AM
AVS Special Member
 
jneutron's Avatar
 
Join Date: Mar 2007
Posts: 1,879
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 17
Quote:
Originally Posted by stereo2.0 View Post

A word of warning, this may be hard to read because:
a) he's not always systematic when going from one cable to the next. (Ex: doesn't go from lowest resistance to highest)
b) his writing style may come off as being somewhat angry/arrogant ....


I choose C...the use of approximations without regard to accuracy.

jn

Some discuss because they can. Others attack because they cannot. (unknown attribution)
A good man knows his own limitations...(Dirty Harry)
Lead, follow....or get out of the way..
jneutron is offline  
post #167 of 170 Old 12-27-2012, 08:33 AM
AVS Special Member
 
jneutron's Avatar
 
Join Date: Mar 2007
Posts: 1,879
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 17
Quote:
Originally Posted by kraut View Post

As you might gather from this website, cables and their effect have little to do with what your opinion is, cable technology has to do with physics and math.

It would be nice if the quoted text were accurate with respect to the discussion of a current carrying conductor.
Quote:
The Skin Effect arises when EM waves are incident upon, or are guided by, conducting surfaces. The E-fields set up currents in the surface and hence the field only penetrates for a finite distance.

It must be understood that the quote on skin depth is an accurate description of e/m waves impinging on a conductive planar surface and within a waveguide.

It is not however, an accurate description of what happens when the fields are generated by a current within the conductor.

That actual verbage is what got Hawksford in trouble back in '85.

jn

Some discuss because they can. Others attack because they cannot. (unknown attribution)
A good man knows his own limitations...(Dirty Harry)
Lead, follow....or get out of the way..
jneutron is offline  
post #168 of 170 Old 12-27-2012, 12:09 PM
Senior Member
 
kraut's Avatar
 
Join Date: Sep 2012
Posts: 379
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 60

Quote:
Is it possible to contain a signal within a copper wire?
Coax's signal "travels" from the center of the core and in the space up to the shield. Right?

I was responding to this question which seemed to be concerned with the skin effect.

Maybe this quote is more precise when it comes to conductors (and not waveguides):

http://www.wheeler.com/technology/technicalpaper2/technicalpaper2.pdf
Quote:
Intuitively, to mimic the skin effect, a conductor can be thought of as made up of concentric shells. At low
frequencies, all the shells are carrying currents, minimizing the resistance and maximizing the internal
inductance. As frequency increases, due to the magnetic field inside the conductors, the inner most shells
gradually turn off and only the outer shells stay active, thus increasing the resistance and decreasing the
internal inductance. This can also be achieved by parallel combination of impedance branches, where
each branch will have a resistance and inductance in series.

http://www.ultracad.com/articles/skin%20effect.pdf
Quote:
The skin effect is the tendency of high frequency current
density to be highest at the surface of a conductor and
then to decay exponentially toward the center. Skin effect
is directly linked to Faraday’s Law and to inductance.
The skin depth is a defined depth used to approximate
the effective cross sectional area of a conductor
when the skin effect is limiting that area. Skin depth is
inversely proportional to the square root of the frequency.
The frequency where the skin effect just starts
to limit the effective cross sectional area of the conductor
is called the crossover frequency, which is defined in
this article.
kraut is offline  
post #169 of 170 Old 12-27-2012, 01:14 PM
AVS Special Member
 
jneutron's Avatar
 
Join Date: Mar 2007
Posts: 1,879
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 17
Quote:
Originally Posted by kraut View Post

I was responding to this question which seemed to be concerned with the skin effect.
Maybe this quote is more precise when it comes to conductors (and not waveguides):
http://www.wheeler.com/technology/technicalpaper2/technicalpaper2.pdf
http://www.ultracad.com/articles/skin%20effect.pdf

That content is better with respect to describing what happens. The why is not described there, but that is probably for the best..wink.gif

jn

Some discuss because they can. Others attack because they cannot. (unknown attribution)
A good man knows his own limitations...(Dirty Harry)
Lead, follow....or get out of the way..
jneutron is offline  
post #170 of 170 Old 12-27-2012, 01:31 PM
Senior Member
 
kraut's Avatar
 
Join Date: Sep 2012
Posts: 379
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 60
Quote:
The why is not described there, but that is probably for the best..wink.gif

Don't want to go there...my physics schooling is rudimentary at best...and my math was nothing beyond calculus and vectors....and about forty years ago.
kraut is offline  
Reply Audio theory, Setup and Chat

User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off