To make your speaker cables faster, just put the amplifier on a top shelf so gravity helps. 🙂
Well, gravity will help electrons going down, but delay those going up, net result being that speaker will become saturated with electrons so getting more and more negative.
Eventually (a couple Million years?) you´ll reach 1 Million volt voltage difference and lightnings will fly.
Eventually (a couple Million years?) you´ll reach 1 Million volt voltage difference and lightnings will fly.
I would not ask you to believe me over Floyd. As you say, what you know about me is indeed "self proclaimed", and on an internet forum..
As to correcting misunderstandings taught in degreed programs...four very simple examples..(complex examples of which there are a lot, are well beyond the scope of an online forum.)
1. I keep running into engineers at the masters level who explain to me that when you increase the number of microsteps on a stepper drive, the torque decreases.. sigh.
In an open loop system, increasing the number of microsteps decreases the incremental force applied to the load as a result of a single microstep. It does not decrease the power of the motor, but to expect the motor to follow smaller steps is incorrect.
In a closed loop system, the force the motor will apply depends on the PID loop parameters, especially the integral ,component. With proper variable selection, a closed loop will provide good stiffening control of the system. Increasing the number of microsteps simply means increasing the PID parameters to accomodate the gain change at the output.
In my work, it was quite simple to demonstrate control of multi-ton objects at the 1 nanometer level static, 25 nanometer dynamic.
Or, I could have simply listened to what was taught to the masters level guys, and go belly up..can't get there from here.
2. It is taught that you cannot run single ended audio signals great lengths without ground loop noise interfering.
I did that in a 450 seat venue with 15 Kw of SCR dimmers, a quarter million volt van de graf, and toro leaf blower on stage. It was a simple thing to solve, so much so that my 8 year old daughter and 10 year old son could setup the sound system in 10 minutes flat. Yah, I carried the speakers and amp, but they did all the interconnect and did the sound checks. Oh, forgot, it was over 100 feet from the mixing console to the amp on stage.
3. Skin effect in round conductors is described by the exponential equation. Incorrect, the exponential equation describes planar waves impinging on a conductive surface normal to the surface.
4. The taught method of controlling a PID loop for a motion control system involves closing the loop using feedback and simply making sure there is sufficient phase margin at zero gain such that the system cannot break into oscillation. What is not taught, is that the BODE plot/phase response of the system is heavily dependent on the magnetic forces being used to control the system. The lower the forces, the less phase margin is available. It is easy to make a system stable when the magnetic forces are large, but when the system moves to a position where the magnetic forces are lower, the phase margin goes away. The programmer is left to marginalize the system accuracy to keep it stable. Or, if properly understood, a lookup table can be generated to adapt the gain based on position (or even motor current). I am working with the really smart guys at two motion control vendors to have them include this understanding in their product line. While their teachings of "plant transfer function" stuff is really great, they have no understanding that the plant function may be dependent on current or previous state.
The understandings of what actually transpires within the magnetic gap with a voice coil is considerably beyond university teachings, but some have a reasonable handle on a lot of it.. You do well to follow those like Toole.. My work is significantly beyond that, but that's nature of the beast. Not too many deal with 12 tesla superconducting magnets, motion control at nanometer level, or half mile circumference speed of light type machines.. as I said, I am having fun.
Eventually, the teachings at universities will catch up to reality. It's not really that bad, but some fine details do indeed require work.
All of us together will advance, the biggest issue is keeping civil during that effort.
John
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JN,
Why don’t you admit you are really institutionalized and the only outlet you have is the internet.
Of course the institution is a renowned national lab!
😉
Why don’t you admit you are really institutionalized and the only outlet you have is the internet.
Of course the institution is a renowned national lab!
😉
I thought that was understood??
Just got a negative covid test, I was going nuts in quarantine...
Having lots of fun with the resin 3-D printer and making silicone molds for one of my children.
It's great using my day job to buy tools for my hobbies..
They hired one guy I pleaded them to get, I am teaching him to replace me. He is good.
Trying to get three more in different divisions.. My close encounter with a bathroom vanity only emphasizes the need to get some young blood in here..
How are you doing? Haven't had a dialogue with you in a really long time.. Hope all is well
John
Sorry, but none of this convinces me that universities are deficient in teaching electrical engineering or need to "catch up to reality" as you put it.
Colleges and universities teach basic principles and how to apply them to real world problems in general. You keep citing issues with regard to a very specific and narrow field that you deal in and there is no reason whatsoever to expect that universities would teach the details of that field.
He has given methods to calculate skin effect depth, and those equations are available on line.
Even as ready calculators....
https://www.omnicalculator.com/physics/skin-depth
Just enter frequency and so on.
Look them up, enter the frequencies in the 100 to 20,000 Hz range.
And draw your own conclusions.
In sum, you must find something else to be OCD about, to satisfy some deep need in your soul.
Be happy, whatever it takes.
Even as ready calculators....
https://www.omnicalculator.com/physics/skin-depth
Just enter frequency and so on.
Look them up, enter the frequencies in the 100 to 20,000 Hz range.
And draw your own conclusions.
In sum, you must find something else to be OCD about, to satisfy some deep need in your soul.
Be happy, whatever it takes.
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You better be careful here. According to jneutron our current understanding of skin effect and the equations that we use to calculate it are all wrong.
There are so many equations available...check a few for comparison.
And yes, 'jneutron' is skeptical, because of practical experience.
So am I, and like I said earlier, does it really affect the sound quality if you connect the cable backwards?
That is the purpose of this discussion, I think.
And yes, 'jneutron' is skeptical, because of practical experience.
So am I, and like I said earlier, does it really affect the sound quality if you connect the cable backwards?
That is the purpose of this discussion, I think.
Zimble, as the Malayalam speakers say in English.....
Find a set of speakers with terminal posts.
Play your favorite musical passage through them.
Disconnect, and reverse the wires, amp side to speaker side.
Use adhesive tape as a temporary marker on one side for avoiding mix ups. Keep same polarity, most wires are made with markings.
Terminal posts make it easy to do so, nothing else is special about them.
Play the same music again.
Tell us what happened.
Find a set of speakers with terminal posts.
Play your favorite musical passage through them.
Disconnect, and reverse the wires, amp side to speaker side.
Use adhesive tape as a temporary marker on one side for avoiding mix ups. Keep same polarity, most wires are made with markings.
Terminal posts make it easy to do so, nothing else is special about them.
Play the same music again.
Tell us what happened.
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Member
Joined 2006
Wish I could still be able to access to the labs at IBM Yorktown where I studied semiconductor physics (yes, in same dept with L. Esaki, R. Dennard, etc.), and from which I earned my Ph.D in EE from Columbia.
I was just trying to offer some scientific insights on the surface states area which happens to be part of my expertise in the past.
Work had to be extra careful then on electrons trapping/ releasing from surface states at any interfacial contacts, and measurements must be chilled to 4.2k for calming down, for the purpose of counting just a few hundred electrons in my devices (and optical studies even down to super fluid helium at 1.8k).
No.. not the micro diodes model they proposed decades ago in bulk copper... but in fact... the whole surface interface of the copper wire could potentially be coated with a thin metal- semiconductor (Cu/ Cu2O) layer, ie, becoming a massive schottky diode, where directionality might come from if indeed it exists (note: not claiming it exists or not).
Once current saturates the wire in one direction as I suggested from the burn in procedure earlier, (and without plastic insulation for ruling out the static random electron trapping/releasing interference), certain electrons could portentially be thrown over to the Cu2O potential barrier side and stay there... and funny things could happen when direction is then reversed...
As for the skin effect, Hawsford and Jung both offered good explanations, and suggested using wire size of about 20 SWG where DC and say 20khz signal both see the same 100% wire cross section, or in other words facing same electrical resistance. (Liz config to be employed for carrying higher current)
Ok, ok, again.. I know, this is offering no experimental proof, I am just thinking it out loud. 😸
Member
Joined 2006
I for one appreciate any kind thinking out loud.... but....
IMHO we need to concentrate our efforts to establish reasonable facts first before making up our minds about mechanisms.
- DBT (of the well-planned and -executed kind) to establish that there is an audible difference when reversing a cable (or switch to different cable, etc). A fact, within the limits of statistics which can be made strong enough for most purposes.
- Have measuring/recording capabilites in situ (preferably sample-synced recording while playback), to catch the speaker input signal (or whatever point of manifstation of a cable phenomen), and record everthing during the test, plus test signals.
- Analyze and try find a systematic difference in the signals that is a reliable tell for the direction change and direction change alone.
IMHO, only when we get this nailed it's due time to dig in deeper and start thinking about underlying models and mechanisms.
In my opinion it is a pretty fair bet that if cables did make such a night-and-day difference in DBT/ABX tests that the hype, sorry, advertising departments of snake oil cable merchants would have jumped on it hard to use as a demonstration and review feature. Remarkably, such testing remains practically non-existent in any sphere of the world of sound reproduction. That's somewhat like testing cars without measuring their acceleration, top speed, and fuel economy, instead deciding which is best by looking at how pretty and expensive they are sitting in the showroom or comparing exhaust notes at tickover...
The markings on cables (text) is by practicality written along the cable and not across - this is not a "cable direction" cue ;-D
If you find a printed arrow on it - be aware that you have / are about to pay a snake tax 🙂
//
If you find a printed arrow on it - be aware that you have / are about to pay a snake tax 🙂
//
Good Afternoon, 14.15 here.
The tape was to mark one end of the cable, so that during swap, the same ends could not be connected again, at the same terminals, negating the investigation...
We await further updates for this suggested experiment from the OP.
The tape was to mark one end of the cable, so that during swap, the same ends could not be connected again, at the same terminals, negating the investigation...
We await further updates for this suggested experiment from the OP.
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