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John Curl's Blowtorch preamplifier part III
John Curl's Blowtorch preamplifier part III
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Old 5th December 2018, 03:21 AM   #11001
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John Curl's Blowtorch preamplifier part III
Certain posts containing personal attacks and their collateral have been removed from this thread. Gentlemen, kindly keep the discussion civil.
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Old 5th December 2018, 06:29 AM   #11002
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For the first measurement became a symmetric XLR cable, of course shielded, used. Once without a small one Slipstream Quantum Purifier, once with each a small slipstream quantum purifier in the signal wires, so a total of two. Measured was directly from the generator output on the analyzer input of Rohde & Schwarz UPD audio analyzer. There were none Filter turned on, bringing a measurement bandwidth given by 300 kHz. Measured became THD + noise, the sum of all Distortions + noise. The upper blue Curve is without the Small Slipstream Quantum Purifiers, the lower curve with these measured. You can do a low, but demonstrable improvement. This is quite audible! Measurements on Large Quantum Purifier The impedance measurement gave very similar results Results. Because of the physical Size of the Large Quantum Purifiers was one Measurement in a coaxial test device not possible. To document the effect, became another measurement setup selected: As signal source served Rohde & SchwarzSUF 2 noise generator, the broadband Noise up 50 MHz produced. This signal was with a 10 MHz sine wave Signal with a Power Combiner mixed. The result without Large Quantum Purifier is the upper blue curve, with Large Quantum Purifier the lower green curve. The 10 MHz signal is in both cases equal in level, so it is not attenuated. The noise floor is around 10 dB lowered. Such a big difference very noticeable in the audio field.
So, they make in all cases wideband (>300kHz, 50MHz) noise floor measurements, the devices are "doing something" - yes decreasing HF transfer like a passive components would - the decrease in HF results of course in reduction of the wideband (HF) noise floor and then they say it would be audible, though no measurement of noise in audioband (BW = 22kHz), except one strange plot with 1dB improvement that might have resulted from repeating error, has been provided. Reduction in HF will be also achieved with any LP filter. In my opinion this deduction from HF noise floor to audibility is a pure pseudo-science and the audio magazine just needed "something" measured to support the claim on sound improvement. I know this situation personally, I was asked several times by local audio producers and sellers to measure "something" on link cables and power cables.
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Old 5th December 2018, 09:26 AM   #11003
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Yes - this 1 db difference in THD+N is really interesting. My inner technician doubts it legitimacy. Yes there where fancy boxes used to do the investigation - but what about the operator? Not 100% convinced. I would have liked to see an independent organisation doing the measurements. A high-end magazine is not. So, not ready to invest in these things and put into my gear. It will take more rigor and stringens to do that.

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Old 5th December 2018, 09:38 AM   #11004
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The most interesting/worthwhile part for me was working out how to do a Google translation, thankfully it didn't take long or cost me anything, my time is really cheap........

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Old 5th December 2018, 09:42 AM   #11005
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Originally Posted by john curl View Post
Take that, you guys! See, I told you so.
A truly awful band, I agree
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Old 5th December 2018, 10:34 AM   #11006
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Originally Posted by scott wurcer View Post
Same here, paid 6 figures to shave microseconds off of electronic transactions. OTOH I have a friend with a brother deeply involved in the grid that claims there are power centers with Win 3.0 computers deathly afraid to take them down for upgrade (there are no longer any viruses that apply).
If we want to keep these people doing what they are good at, they will have to be paid better, but I don't know that it can ever match what the finance industry can do. The only people that will stay in research are the ones that are not motivated by money and there are only a few of those. Kudos to DPH, but when he sees his buddy driving down the street in the latest Porsche, you can't blame him for wanting change career path.

Power centres running stuff under Win 3.0. Ouch! I'd be afraid of getting hacked
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Old 5th December 2018, 10:45 AM   #11007
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I can see that it is everywhere the same with salaries in science. I had worked in two scientific institutes, those were the most interesting years of my career, however paid badly. Finally I started to co-operate, on long-term consulting basis, with a US company on quite unique industrial technology and this made my income very reasonable.
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Old 5th December 2018, 10:58 AM   #11008
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Many years ago I worked in the power industry, then for the power industry as a consultant. Back then we used PDP11 running mainly home-grown software and home-grown networking. Not a TCP/IP stack in sight. No external connections.

Then they wanted to get data from the plant to the PC on their desk. The PC on their desk was on the office LAN which was connected to the internet. I worked out a way of doing this fairly safely, but warned them that it reduced security.

Then they noticed that PCs were much cheaper than PDP11 or PLC, so PCs started appearing at the plant end. Then the IT people issued an edict that all PCs came under their control, and must be on the LAN so they could be 'managed' efficiently. I warned them that this would be throwing away security, and anyway the IT people would not understand the special requirements of a PC doing plant control (e.g. don't try to 'upgrade' it overnight to a new system version which was not supported by the SCADA software). About this time I left the industry and went back to unversity.

I now hear dire warnings about plant computers being hacked, or facing threats of hacking. Why do people not know that you cannot have something which is both connected (so you can see the data) and isolated (so it is safe from external interference)? It is like a newbie designing a PSU with the wrong transformer, so he wants to run two separate PSUs from one CT secondary.

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Originally Posted by john curl
Different energy states in electrons, not good or bad specifically.
So noise/distortion etc. gives rise to different electron energy states in a conductor from music? I'm sure a proven Maxwell demon would easily score a Nobel prize.
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Old 5th December 2018, 11:01 AM   #11009
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John Curl's Blowtorch preamplifier part III
Sadly the whole 'IOT' rush has opened up many security holes and, after 10 years of chasing unicorns look very much like SCADA, just in the cloud and not as good! There was no lessons learned from the past, which seems the valley thing!
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Old 5th December 2018, 11:06 AM   #11010
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There was no lessons learned from the past,
Isn't that always same?
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