I don't think that to be true. But, for once, I believe that JC was right in his evaluation.
My experience, exactly. I dont have a hatred for Scott or others here for any of their real knowledge. What ever that might be. If it isnt in my own sphere of knowledge, I am sceptical what is told here. Frankly, some of it just isnt very convincing.
At LLNL EE and ME are there to support Physics. But, EE also has their own Ivory Tower - Bldg 131, second floor. between project jobs, I was asked if I would like to work with EE doing research who needed notes and data put into a paper for publication. Or at least roughed out for them. I went and was interviewed. I said it would take me a few months to be able to catch up and understand enough to contribute. That was too long. The pressure to publish was so high, the EE needed to publish but that takes so much time away from his research. What a problem....
-Richard
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This reminds me of philosophers debating on angels on the head of a pin.
OK. I'll run some tests on the Quad this week.
1) impedance vs frequency both magnitude and phase at different levels at different line voltages. This is pretty straightforward and easy.
2) maybe acoustic measurements. I don't have a good space for them but if 500 Hz up I may get useable results.
As I remember the Quad transformers are pretty sophisticated. I think they are cut cores. The lams are pretty thin. The ratio is quite high and the secondary is pretty fine wire. Two transformers are used so the ratio required is halved. I'll measure the secondary voltages as well. Finally another use for the two P6013 probes.
OK. I'll run some tests on the Quad this week.
1) impedance vs frequency both magnitude and phase at different levels at different line voltages. This is pretty straightforward and easy.
2) maybe acoustic measurements. I don't have a good space for them but if 500 Hz up I may get useable results.
As I remember the Quad transformers are pretty sophisticated. I think they are cut cores. The lams are pretty thin. The ratio is quite high and the secondary is pretty fine wire. Two transformers are used so the ratio required is halved. I'll measure the secondary voltages as well. Finally another use for the two P6013 probes.
Yes he did, no charge movement above 1Khz.
His latest comment tells another story.
I don’t know of any public documents describing the transformer, anybody ??
May be, but I give a series inductance by far the highest probability.
In total this could easily be a month work, nice for a graduating student but a bit too much for me.
But starting with an impedance curve for various levels and various HV voltages would already reveal quite a lot.
Same can be done for a 1 meter distance recording of the sound on the speakers axis when the impedance curves shows dependencies on HV.
That’s as far as I will go.
I also have balanced cables to compare as I promised Bill. 😀😀
Hans
And those in the middle who know nothing about anything but manipulating people one way or the other.
I've worked cores from 500 micron to 15 micron lamination thickness. The 15 micron material I used for a 20Khz transformer almost perfect for ESL's, as output voltage was in the kilovolts, and I had to transfer 1500 watts. But man, the edges of that foil is just deadly.
If any of the windings get close to the cut, there will be significant excess dissipation there, as flux lines bunch, which is toast for the copper of the windings. A significant disadvantage for gapped cores.
I'd probably worry about 1khz up. Really accurate measure should not be justified, as if they could hear it (kitchen or otherwise), it should show up in the measurements easily.
jn
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Hi Demian,
While I was still typing you published your posting suggesting the same measurements as I proposed.
It would be nice if we could compare results.
Hans
Try..., yeah, that's the keyword. Nobody can stop you from trying.
As you've noticed..., yeah, that's the crux of the matter, isn't it. It's also known as your opinion.
Thats very true. Does not change the fact that their results do not often pan out in the field when a lot more people use the drug..... often not DB data btw (Dr and patient opinions). The dbt pharma used to get the OK to sell, often turns out to have different results than their dbt indicated when subjected to larger size over longer time over many cultures.
DBt in audio listening is just like that.
THx-RNMarsh
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Please reduce the bias Z to simulate leakage and test also.
Look at the top HF region.... ESL are known for their fast Tr and dont sound dull. See if you get same heavily rolled off HF as Stereophile shows. Which would sound dull.
I was wondering if their rolled off Hf end was due to low HV or leakage because of what i measured at our friend, R.Lees.
A common thread is that R.Lees and myself and here in Bangkok all are near the ocean with high humidity. Since having them in bangkok, the QUAD repair people here say cant use QUADs in high humidity. Seems to be a well known problem with QUADs ?? At least over here.
THx-RNMarsh
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Double blind tests, something you don't do, is? Got it.
Which medicine can you cite as an example of that?
Which listening test result can you cite as an example of that?
Hmmm The Aircond has a DRY mode for this high humidity environment... mildew etal. Dry out the QUAD and room air and retest.
-RNM
-RNM
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I lived in Asia for 10 years (Japan, Taiwan and China) - the humidity thing in Japan and Taiwan was brutal. First few days in Japan (August) I thought I was being smart by opening the windows, but soon learnt that was a no-no. The carpets actually felt 'wet' that's how humid it was. Even then, we ended up with those buckets with crystals in them that soak up the moisture and turn to liquid in every cupboard.
You wont really get a cool season in Bangkok - unlike Tokyo and Taiwan - so it will be a year round battle I'm afraid.
Small wonder the Quads wont work in that environment! Best thing is to leave the sound room aircon on 'dry air' permanently!
You will have to do better than just spewing out claims.
Expecting the bodyguard to jump on me.
His analysis is purely membrane deflection caused radial movement of charge due to membrane curvature in an e-field that is straight and normal to the film. That in itself will be frequency limiting as the deflection falls with frequency.
On the other hand, an ESL with rings by design, applies non normal lateral e fields to the film via ring delays. Obviously well outside the scope of his paper. But I can see that segmentation delay causing significantly higher charge movement simply due to angular field generation.
To wit..if the hv bias is infinite, the stator efields at the film between rings will be perfectly normal to the film surface. With no bias field, the inter ring spaces will have significant lateral e-field component, and as bias climbs from zero, the vector summation will have less and less relative lateral field.
How it plays with frequency would not be an easy calculation, I suspect polar response would be an easier way to see it.
Perhaps. But I would have suspected the peak to be considered at initial design, so find it interesting. Measurement of the transformer to me is by far the easiest to do, but I always remain wary of the "if all you have is a hammer, everything is a nail".
jn
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