Jim was my last adviser, he didn't believe in me which I understood because I was in a bad mindset at the time but we were friends all along. I had to make my own escape plan. A few months later I met Barrie and we have been friends for decades. Funny how things work out. Jim was a huge model railroad fan and I saw some of his collection at his memorial service, reminded me of that Variac my father gave me that made everything work better.
They deserve the ‘Crystal Mark’ for speaking in plain English.
For non UK readers this is a mark of excellence issued to documents, texts etc that meet the criteria of clear, concise prose.
I just wish they’d get involved in legal documents. Some of that stuff is so convoluted by the time I get to the end of a 600 word, punctuationless paragraph I’ve completely forgotten what the beginning was about.
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This still needs a little translation into some hard details. Not many folks have observed the focal plane of LIGO, you basically see the cancellation of two extremely intense laser beams with the noise of the atoms moving in thermal equilibrium on the reflecting surface as the visible image, it's a profound experience to be there. There is a Japanese program to cryo the mirrors but I have not been in touch on any of these other initiatives.
JC
you will need at least to borrow some test equipment to possibly determine if that is the source or analyzer distortion.
Demain has Victor's oscillator which is fairly well characterized at this point and can help with that, if I could volunteer him for that
That will help determine some of the answer to you question. Ed's procedure is another.
Oh, and try it at different levels to see the consistency.
The other question is if the calibration still holds today as I see that was done in 2012.
Cheers
Alan
you will need at least to borrow some test equipment to possibly determine if that is the source or analyzer distortion.
Demain has Victor's oscillator which is fairly well characterized at this point and can help with that, if I could volunteer him for that
That will help determine some of the answer to you question. Ed's procedure is another.
Oh, and try it at different levels to see the consistency.
The other question is if the calibration still holds today as I see that was done in 2012.
Cheers
Alan
LIGO has to be the absolute pinnacle of engineering. Astounding stuff.
(My earlier comments were somewhat tongue in cheek - but not the bit about the leagalise!)
Except they don't actually explain what is being done particularly well. I know finding journalists who can tread the fine line between confusing the reader and fluffing it up to the point of being meaningless are few and far between, but this to me was a particularly wide miss.
Edit: your second post explains the first
Easier do do than you would expect. Just look at an attractive woman and you will share some of their thought processes! (Einstein in particular.)
Because it is the measured impedance.
Many speaker designers will recognise that window as Audiomatica Clio System as used by professional designers. Like Roger Sanders, originally of Martin Logan fame. I spoke to him on the phone and we agreed that Clio is now the loudspeaker industry standard. But it can do a lot more than measure speakers. It can also measure electronics.
The above measurement is 100% real and correct, so I now must wonder if anything you say from that point on has a credibility at all, no validity, period.
Seems that in your haste you have drawn some really bad conclusions.
No commercial speaker has a more resistive impedance than the Elsinores.
There are plenty of people out there who have Elsinore Mk5 and Mk6 speakers, anybody that has access to them can do a simple measurement to assure that the impedance is extremely flat, in fact, I encourage builders to make it in order to be sure they have gotten the crossover right.
So really you owe me an apology and below you will see why.
Since that is a 2KHz voltage square wave and the current of the amplifier to the speaker is also a near perfect square wave.
This 2KHz current square wave is another proof that the impedance is flat from roughly a decade below and a decade above, from 200 Hertz to 20KHz.
A measurement like this does not lie, and you know it!
But I suspect you will not apologise despite the proof below that your hasty look at the crossover, you totally misinterpreted what it does.
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Hey Vac,
Not sure about smokin' amps but I think you've been smokin' too much of that Amsterdamsky coffee shop weed.
For the tweeter network, which you are referring to, at 2700Hz I get about 25 ohms with a 6 ohm resistive tweeter load.
T
Thanks Terry. What went through his head I do not know. You are quite welcome to come here and supervise an impedance measurement that I can do on the Elsinore Mk6 here - and then report it to all and sundry here. I would love that. The thought did occur to me, what was he taking when he was looking at that. And couldn't he find a calculator (?) that should have been enough.
PS: Look at that 2KHz current square wave I posted, a few things happen when you get this kind of result, no reactive current from the amplifier and also effectively cancels out the output impedance of the amplifier. My current amps here are 2.5 Ohm to 5 Ohm and there is no change in the amplitude response of the amplifier. Why is that accepted as some kind of achievement, even a small one?
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Finally something we can agree upon !!!!!
Driver imperfections have a double-whammy when driven by a voltage source. Now that statement is almost sure to raise your ire.
So consider me incorrigible. A naughty child that won't shut up.
Oops, you Americans have a different meaning for naughty?
Driver imperfections have a double-whammy when driven by a voltage source. Now that statement is almost sure to raise your ire.
Not at all, all well known. I guess you choose to ignore my points so be it, it won't make your speaker current driven that's for sure.
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