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Equal length wiring
Equal length wiring
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Old 25th July 2021, 05:16 AM   #31
PRR is offline PRR  United States
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Equal length wiring
If L/R length matters, we have to sit ON the center between our speakers to sub-micron accuracy, because speed of sound in air is so much slower than speed of audio in wires.
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Old 25th July 2021, 08:06 AM   #32
Jazz Man is offline Jazz Man
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Exactly, and time delay is not the issue hpro imagines it to be. Phase shift is possibly an issue.
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Old 25th July 2021, 08:51 AM   #33
hpro is offline hpro  Switzerland
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That's only my opinion. everyone free to have it's own opinion in this matter..

When we sat in the nineties in Hifi House in Bangkok, there were guys who could hear out what kind of CAPS were used in AMPLIFIER. What Kind of Cables between the devices. I was there and have seen it..

I do agree that for 1 or 2 inches it (may) don't matter.. and I can not tell you if this matters, in the circuit, but for me I try to design my Artwork, so I do not need to find errors when it don't sound the same because of different sizes and lenght of connection tracks, or cable connections. I have had that recently on speaker cables, Measuring distortion while testing an amplifier Ciruit. and just because that pair of speaker had not exactly 8 Ohms.. then Exchanging Cable to a shorter one removed the problem.

In the early Nineties, I was in love with a beatifull Thai Lady and her father had an Electronics shop in Chiang Mai, Thailand. I went to help him to build his Amplifiers he build and sold there..

Mosfet 2SK176 with 2SJ56 *If I remember rigth* it was a copy of Hafler DH-220..
And we had always problems when connecting Speaker cables with more lenght than 5 Meters. I know that cause has nothing todo with this here or only little. But again shorter Cable did not Oscillate. Ripping the cables apart did not solve the problem, but shortening the cables down to 1.5 meter and all Oscillation was gone.
So please forgive me, I stand up that length matters.

thanks you for understanding.
Let me ask one more question:where is the problem to desing something evenly, that whatsoever no chances are taken that because of not distribuiting Current Voltage, energy evenly, will bring up problems. Even if don't matter as you guys write, OK with me, but I do not like to TAKE CHANCES and then to find out, why afterwards instead of listening and enjoy music which is played, sound is like a trash can.!..

Any one can look a this as he likes.. I do not try to convince anyone to change his mind, but I have seen to many examples where cables and wire were the culprit.!
thanks

Last edited by hpro; 25th July 2021 at 08:54 AM.
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Old 25th July 2021, 11:18 AM   #34
Tubelab_com is offline Tubelab_com  United States
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Quote:
Originally Posted by hpro View Post
Sound is moving in one second only 300Meter as far I remember, "speed of sound in dry air at 20 C = 343 m / s"

Speed of electricity In copper at 60 Hz, 3.2 m/s. this is what wikipedia tells me..it goes faster with rising frequency At least that's what I have seen also many time..
So, according to this sound of multiple frequencies travels at roughly a constant speed in air which is roughly 100 times faster than the same electrified sound travelling through the wires to the speakers, and that electrified sound will have a different speed of travel dependent on it's frequency with the treble arriving before the bass.

How then did I ever get outdoor speaker setups for live musicians to work where the speaker cables were over 10 meters long? Ever try to play a guitar when your monitors are delayed by even a few mS due to digital latency in a DAW or other signal processing equipment?

Live music would be impossible if the monitors were delayed by hundreds of mS, so every musician would have to use exactly the same cable at exactly the same length. Some instrument cables are rather long, and some instruments use no cable at all (wireless transmitter). The cables from the amps to the speakers are not all the same. How is it that all the sound is in sync?

Try this simple test. I have a test setup in my lab currently for working on reasonably powerful amplifiers. There is 50 feet (15.24m) of speaker wire connected between each output and the portable test speakers. This is so I can place the speakers in a closet to test at high volume levels without blowing my ears or upsetting the neighbors. I can plug headphones with a 1m cable into the same amp and run them concurrently.

Even with over 15m of cable the sound from both sources appears to be in sync.

There are plenty of ways to verify that WickedPedia is wrong in this case. I have shown a few, and I refuse to take this bait any longer. It just tastes bad.

Try some of these experiments for yourself or just think it through. Most of the tech we use today would not be possible if "electricity" in a wire only moved at m/S speed.
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Old 25th July 2021, 11:54 AM   #35
Charles Darwin is offline Charles Darwin  United Kingdom
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Wiki may not be wrong here because the 3.2m/s hpro refers to is according to wiki the speed at which electricity ENTERS a copper conductor, not the speed at which it propagates once it has entered.
I would imagine that the distance at the entry point is non-zero but at the same time very, very short indeed.
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Old 25th July 2021, 12:03 PM   #36
hpro is offline hpro  Switzerland
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There might be some misunderstanding what with the MEANING Of electricity is meant.
So, not to being stubborn, or likewise, 3.2M/Second is the fastest they move. I think the article I place that link from wiki. Is real clear.

If I search the German sites, then it's even worse because there this would advance a half Centimeter/Second.. In favor for the community, and all relevants here
Yes you are right, and I know that, Voltage Travels about the Speed of light, but voltage alone will not shot any Goal..and I'm not in here to Question your thoughts.
But build on these statements, you can find on Wikipedia, because these are real relevant sources there, the Economy is build and many businesses function because on that knowledge.

I respect your aspects, I respect you as the person I see here, and I do not in anyway say that your wrong.

Just this. Each Cable has a resistance, right?

Each material in a cable has a resistance, right?
Do you think, increasing the length of that material would increase resistance?
I give you a link where you can see this in FACTS.

Damping Factor with Calculator
Then scroll down until you can see that picture I send with this
Then change the to three to following 1 1 4 100 24
24 is the gauge of a Tweeter Wire for about 25 Watts..
hit "Go figure and read the outcome" Now change the length of Speaker wire to .5 and look whats happen. And read all these Parameters, it might be interesting for you. it is certainly for me.

This will show you that length matters.
May you like to read about AWG some to compare with resistance. If there is a change in resistance for 1meter the change will be there for 1cm as well this is 1/100 of a meter.
AWG Wire Gauges Current Ratings
If the length of the cable differs and the diameter does NOT differ, also then Length matters.
I do not have more or better examples than this. So, Thank you for this interesting communication.

BTW I didn't write this what you can read in all these links, I just pasted them for you.
To accept or not accept that is up to you, and not all what one reads on sites needs to be true. This also counts for myself. But I did measurements, and I have to equipment todo so here at home.. and if wouldn't had run into problems, then I would not write here.
But may I'm completely wrong. That's another possibility. So,no offence meant..
Have a nice sunday.
Respect Regards
Chris Hess
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Old 25th July 2021, 12:24 PM   #37
Charles Darwin is offline Charles Darwin  United Kingdom
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My speaker cable has a resistance of 4.5Ω per km.
The lengths I use are meters so thousandths of Ω max difference. Not audible.
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Old 25th July 2021, 01:13 PM   #38
Tubelab_com is offline Tubelab_com  United States
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Nobody disputes the fact that every conductor is imperfect and has electrical resistance. Silver is the best common electrical conductor and copper is also pretty good, Aluminum, steel and gold are not as good but have some other properties that make them useful as wire.

The length and diameter of a wire will determine it's resistance, and of course a longer wire will have a higher resistance than a shorter wire. It is well known that long or small diameter speaker cables will cause power loss, just as a long extension cord will cause a drop in line voltage to a high current load.

Any resistance in the path between the amp and the speaker will influence the damping factor seen by the speaker, as does the components inside the speaker cabinet itself (crossover network).

All of the above statements are based on sound engineering principles and not disputed. Whether or not they make any difference in a typical home HiFi setup (especially a few cm of wire inside an amplifier) is a matter of personal opinion and marketing skill.

I can not believe that an audio signal flowing through a wire moves at m/S speed, and demonstrated with many examples that it does not. Much of my work at Motorola, especially in RF PC board design relied on calculations based on DC, audio, digital, and RF signals propagating along a copper conductor at a fraction of the speed of light, usually between 50% and 70%.

This speed is based mostly on the surrounding dielectric material slowing down the propagation due to distributed parasitic capacitance and the conductor's inductance, and not on the copper itself. Air and all non conductors are a dielectric material. Special PC board materials were developed specifically to slow down this propagation at high frequencies in the 1 GHz and above range so that microwave amplifiers could be made large enough for repeatable production on PC boards instead of high K ceramic substrates which are particularly slow (20 to 40% of light speed). Without this work done in the 80's and 90's your cell phone would not exist.

As for the wiki showing that the speed of electricity being slow in a copper wire and varying with frequency, I believe that there is some confusion with respect that the fact that the movement of electrons stops and reverses it's course repeatedly with AC current. If the wire is long enough the electrons pushed into one end never make it to the other end. They just push other electrons out.

When you get deep enough into the details all real conductors are not perfect, and therefore semiconductors. Things get real complicated when it comes to semiconductor physics, a branch of electronics that I successfully avoided throughout my 41 year career despite working for a semiconductor manufacturer. I an not of the mindset to try to figure out exactly how all those calculations were derived or what they really mean.
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Old 26th July 2021, 03:48 AM   #39
PRR is offline PRR  United States
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Equal length wiring
The electrons move slower than the electric wave. Same as ripples in the river move faster than the water flows to the sea.
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Old 3rd August 2021, 10:48 PM   #40
lgreen is offline lgreen  United States
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Think of a wire 100 atoms long, current will move 1 electron to the next atom, which will move 1 of its electrons to the next and so on. This happens so fast that the last electron will shoot out nearly at the speed of light.

But the first electron has only traveled 1 atom in distance, as have the rest.

So is the disconnect here that if we wait for that first electron to come out the end (traverse all 100 atoms) we are in the 3m/s range? Still seems a little slow...
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