John Curl's Blowtorch preamplifier part II

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Ok and with Peeking ...... if you knew which had 480 and which had 720 and 1080 and 4K and 8K..... and you looked at each of them and said you could see a difference and further that you could tell which one was more accurate picture.... greater detail and more accurate colors, etc, would that viewer be wrong because he peeked?

No way to tell because the experiment was not designed correctly. You can't draw valid conclusions from an invalid test setup.
 
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I'll order one later today from RS and give it a try next week. Can't do any harm!

For audio, I would use a much larger value across the lines. But to ground, the C value must be limited to a safe leakage amount.... in USA <4mA.

Leakage Current Standards Simplified | MDDI Medical Device and Diagnostic Industry News Products and Suppliers


Also, if you notice the level I was reading on the CATV was much higher than this safe amount. That is because I had several products on line... each contributes leakage current so the total may be unsafe even if each individual equipment is 'safe'.



THx-RNMarsh
 
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On the topic of clean power for our audio, here's a business opportunity:

Get one of those new Tesla Power Bank home super batteries, around $ 3500 for iirc 6.5kWhr.

http://www.bbc.com/news/technology-32545081

Slap a nice High End sticker on it, sell for 8k and you're done.
Probably even measures good. And runs your coffeemaker in the event of a black out. Win-win :cool:

Jan
 
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Well, Richard and I belong to the group who actually have confidence in what we see and hear. As far as seeing, I can be fooled more than some of my more attentive colleagues due to my own vision problems, but when it comes to hearing, both Richard and I are most probably MORE EXPERIENCED in listening to audio differences, and we have come to trust our ears over the decades of having some of the best listening equipment, as well as participating in listening tests, including ABX double blind, one of which we both participated in back in 1980 or so. We both came out about the same sensitivity in this ABX test, BUT 2 others, people who were actually at audio reviewers level, did BETTER than us! In other words, we are just above average in the audiophile scale, and others can actually discern differences sometimes better than us.
Now, we operate and convey our opinions based on what we hear today. IF you want to ignore us, do it at your own loss, since we are both audio designers who have a lot of experience in just about every area of audio design.
 
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Complete and deliberate non-understanding of sensory experiment design.

Sure SY. Right.

Even if 100% of every man woman and child on the face of the earth can see the improvement in clarity or definition from 480 to 4K... their perception doesnt matter if they peeked. You throw out their perceptions.

I'll stick with the meta-data volume for more accurate results.

Peeking doesnt matter as much as you think it does with some questions. But makes for a nice clean test for test to test comparisons.


THx-RNMarsh
 
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For audio, I would use a much larger value across the lines. But to ground, the C value must be limited to a safe leakage amount.... in USA <4mA.

THx-RNMarsh
Richard,
Why are you referring to current to ground as "safe or unsafe"? Leakage to ground is not unsafe. The limit of 4 mA is because of the trip value of GFCI units for human protection.

The link you posted refers to leakage that can go through a human body, not leakage to ground.

John
 
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Richard,
Why are you referring to current to ground as "safe or unsafe"? Leakage to ground is not unsafe. The limit of 4 mA is because of the trip value of GFCI units for human protection.

The link you posted refers to leakage that can go through a human body, not leakage to ground.

John

The leakage to ground can become the current thru you to ground. So it must be limited.

-RNM
 
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I am sure you tested this hypothesis, so it must be true.

You need to look no further than the medical/Pharma industry in this country.... DBT say all is good but when it gets out to very much larger numbers (the meta data) a very different picture sometimes emerges. And, it is That info which is considered to be more valid and important nor thrown out as not matching the results of the DBT. So, the DBT is an important first step, only.



THx-RNMarsh
 
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Aren't we discussing ground loops in fully grounded systems, where two grounds causes unwanted currents?

John

We are discussing ground loop cause and prevention AND ac line line noise filtering. Multi-tasking going on.
UL takes into consideration of faults in wiring, grounds and equipment. Thus GFI, fuses etc. And, there may be situations in their mind where you become a better return path than the existing paths. So, you need to heed their limits (and IEEE) with regards to ac filters.

-RNM
 
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JN,
Somehow I thought that Richard had transferred to talking about grounding in test equipment, not sure how that happened but that is what I thought changed here. Perhaps I missed something.

It's been difficult to follow, I will admit. But the his last post referred to audio and I think, filters acros the line.

Typical line filters do run some current to ground, and 4mA is the limit due to unwanted trips in GFCI's. But a filter sending current into a three prong cord can push amperes with no danger to humans unless the ground bond is broken.

That's why I didn't understand the link to human electrocution limits..
John
 
I'm often amazed at the hyped complaints or fears - do the sound propagation in air path length and tell me if you speakers-listening position are located that precisely

It matters a hell of a lot if you are trying to configure a measurement system with it. Not a lot if doing hifi playback.

(oops.... context: whether it matters if channels are a sample out of synch in a soundcard)
 
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