BS meter pegging red.
I guess you have your own private subjective definitions of "slew rate", "single tone", "complex tone" (whatever that is), "more square".
Those pesky pitchfork wielding engineers use universally accepted definitions, and a common body of knowledge, which makes the above quoted statement a total nonsense.
You crawled under the radar beam and you managed to buy all that expensive Hi-End stuff undetected?
Unbelievable
Plus you are conservative hereYes, you would need vinyl with 40dB S/N, 16dB crosstalk and 3% distortion. Then speak about wires!!
Up, down, wtf?
http://lightningsafety.com/nlsi_info/Fundamentals-of-Lightning-Rakov.pdf
George
Sparks have little to nothing to do with Maxwell, EM field propagation, and EM field energy transport, but with material properties in an EM field. Paschen's law is your friend.
A vacuum arc, has a completely different physics, with field electronic emission, or thermionic emission, or both, as a foundation. Also little to nothing to do with the EM field propagation.
The arm I have had since 1996. The cartridge I got a couple of years ago for £80 with a coil out and cantilever missing. I could not afford new replacements of either at the current silly pricing for high end stuff.
Sometimes as a parent (well most of the time really) it's hard to know the right advice to give kids. In my case I've ended up serving as a warning rather than being a good example!
So Eldest has just finished finals and hunting around for options to get piled high and deep. I advised her to get out of UK for the time being until the bloodbath of Brexit has finished and funding of sciences is sorted out. She's currently in Marseilles being interviewed for a place there which actually sounds like the perfect place to spend a few years but now discovers she has a videoconf interview with Lund in Sweden on quantum magnet research, which she thinks is more her thing.
So she's asked me what to do if offered the French place tomorrow. Does protocol allow one to ask for a week to consider if you've accepted the free flight and accomodation? Being a ficky I have no idea.
So Eldest has just finished finals and hunting around for options to get piled high and deep. I advised her to get out of UK for the time being until the bloodbath of Brexit has finished and funding of sciences is sorted out. She's currently in Marseilles being interviewed for a place there which actually sounds like the perfect place to spend a few years but now discovers she has a videoconf interview with Lund in Sweden on quantum magnet research, which she thinks is more her thing.
So she's asked me what to do if offered the French place tomorrow. Does protocol allow one to ask for a week to consider if you've accepted the free flight and accomodation? Being a ficky I have no idea.
Am-I mistaking ? I had been told, at school that it was the opposite: from negative to positive.
Exactly so, I mentioned 5KHz as the max harmonic for bass. 1 or 2KHz hearing loss is not what is generally considered normal age-related hearing loss, AFAIK. How many 60 - 70 year olds on here have such HF loss?
When Benjamin Franklin first decide on positive and negative he thought of electricity as a fluid going from a supply to a deficit. When the current actually radiates from the negative source the current begins to really flow when it reaches the positive end. This starts the arc for some cases which grows back to the actual source. So he decided it flows from positive to negative based on observation. It was much latter that folks realized it moved the other way.
So convention calls current flow from positive to negative. Others sort of correct this by say electron flows from negative to positive.
You got it right at school.
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Nice.
Do not think of it as free flight and accommodation. Tell her..if she had five interviews in different countries, they all would have done the same.
They are trying to get the best, and understand that to get young talent, flight and hotel is the cost of doing business. After all, what's a few grand when the payback could be a world leading employee at a facility that lives for that.
She needs to evaluate the offer and the work on its merits. Btw, nobody expects a answer before they hang up. If they push too hard, something is amiss.
Wish her luck. She can pm me should she wish. (I can't think of any good reason she would want to)
Ps..tell her it is more important to follow your passion. Too many follow the money, too many listen to the adults...(watch butterflies to blackbirds for that reference)
Jn
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Not quite sure what you are getting at. The issue is not the breakdown voltage or mechanism. It is the field propagation method. Wave theory and particle theory both cover this.
Seems JN supports the intelligent lightning theory! (Possibly the most intelligence around here!)
I'll go by the spherical propagation wave front until something happens.
It seems to match practice and observations decently.
Anyone have a paper to the contrary?
Well...no papers yet. Not sure if or when they will publish.
As a gradient rises, eventually a breakdown occurs. Most people think lightning occurs when the dielectric withstanding is exceeded. That is not the case.
At some point the air breaks down. This is not a bulk gradient failure, but a local phenomena. That initial spike of conductivity propagates along the gradient, until it hits ground.
You are perhaps 50 years back.
It was interesting researching all this stuff for the dark matter liquid argon detector, I get involved with the weirdest stuff..
Jn
As a gradient rises, eventually a breakdown occurs. Most people think lightning occurs when the dielectric withstanding is exceeded. That is not the case.
At some point the air breaks down. This is not a bulk gradient failure, but a local phenomena. That initial spike of conductivity propagates along the gradient, until it hits ground.
You are perhaps 50 years back.
It was interesting researching all this stuff for the dark matter liquid argon detector, I get involved with the weirdest stuff..
Jn
Ah JN,
I thought the issue was what effect the cable has on the loudspeaker performance.
So I measured a loudspeaker cable intended for portable stage monitor use. Test frequency was 1,000 hertz.
The 25' 12 gauge loudspeaker cable measured .208 ohms, 8.5 nF and .0052 mH.
My arithmetic shows 2 x pi x .0052 mH x 20,000 Hz = .65345 ohms. So 25' will be less than a dB at 20,000 hertz. Just from the cable inductance. Of course that is for an 8 ohm loudspeaker.
Or for a simple stadium run of 250' -2.5 dB at 8,000 Hz. compared to a a 1' length of cable. (Remember it is not just straight resistance.) Yes without equalization you will hear that.
I thought the issue was what effect the cable has on the loudspeaker performance.
So I measured a loudspeaker cable intended for portable stage monitor use. Test frequency was 1,000 hertz.
The 25' 12 gauge loudspeaker cable measured .208 ohms, 8.5 nF and .0052 mH.
My arithmetic shows 2 x pi x .0052 mH x 20,000 Hz = .65345 ohms. So 25' will be less than a dB at 20,000 hertz. Just from the cable inductance. Of course that is for an 8 ohm loudspeaker.
Or for a simple stadium run of 250' -2.5 dB at 8,000 Hz. compared to a a 1' length of cable. (Remember it is not just straight resistance.) Yes without equalization you will hear that.
You might find the language and methodology interesting in Franklin's original papers. I think in this one he picks positive and negative, "until the philosophers show us better". I'm not sure what lighting and sparks have to do with audio.
Letter from Benjamin Franklin to Peter Collison dated May 25, 1747 – Benjamin Franklin Historical Society
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You have seen and read my posts. Apply what I have shown.
Or, ignore everything. I do not care.
Your choice.
Jn
Take your pick, if you reverse polarity of just one speaker, one channel will sound 'correct' with natural sound recordings and the other will sound 'wrong'.
You can then swap interconnect directions around and explore the sounds of the four permutations.
The sound of one permutation will be best, one will be worst, the other two will still be 'wrong' for a given recording.
Dan.
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