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Old 25th August 2012, 05:52 PM   #26971
bcarso is offline bcarso  United States
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Quote:
Originally Posted by jcx View Post
some of us “egg heads” occasionally put our hands on hardware

was climbing yesterday, may again tomorrow

I spend 3-4 nights a week in the climbing gym – my impression is that at least locally near half of the climbers are engineers, grad students, post docs, researchers, professors... technical/scientific professionals

dining after climbing in the gym this last thursday the table had 2 associate professors, 2 software engineers, one who also runs a martial arts studio, a RN and myself


wrung about as much info as I wanted from my IXYS kV depletion mode Mosfet casoded opto isolator electrostatic amp's point-to-point proto last week - sims and 'scope agreed remarkably well on compensation overshoot, ringing damping with the 20 yr old DIP op amp from my parts drawer in the front end

next step for the amp will be PCB to use faster, better op amps available in smt only - sim looks better with 90 MHz GBW op amp - need to remember how to use Eagle again

30 years of EE employment has given me the impression that good theory is good for practice

and stereotypes, caricatures aren't often that useful dealing with real people, technical arguments, or hardware
I could do geek and nerd and introvert on TV, as they say. I usually get into trouble by being too social, not the other way around.
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Old 25th August 2012, 06:35 PM   #26972
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My current project in Seattle had a crew of climbers mount the loudspeaker clusters. First time this happened. They managed to get approval to use climbing gear on an OSHA site.

Last edited by simon7000; 25th August 2012 at 07:04 PM.
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Old 25th August 2012, 07:22 PM   #26973
bcarso is offline bcarso  United States
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I know a famous (within the discipline) free climber who lives out near Bishop. I wouldn't try that sort of thing for all the tea in China. However, I think the more potentially risky practice is his penchant for ayahuasca
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Old 25th August 2012, 07:49 PM   #26974
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Free climbing or free soloing?
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Old 25th August 2012, 07:57 PM   #26975
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Quote:
Originally Posted by simon7000 View Post
My current project in Seattle had a crew of climbers mount the loudspeaker clusters. First time this happened. They managed to get approval to use climbing gear on an OSHA site.
If you're lucky you could get a local Butoh troupe to perform on it. Butoh Dance Performance in Japan - YouTube
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Old 25th August 2012, 09:42 PM   #26976
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Quote:
Originally Posted by simon7000 View Post
Unfortunately you are comparing apples and bananas. When you are talking 105 db. peak levels that is read on a standardized sound level meter. If you wanted to accurately record this you would want at least 10 db. of headroom.
I'm quoting textbooks from forever. Here's one:

Textbook of Hearing Aid Amplification - Robert E. Sandlin - Google Books

Thanks,
Chris
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Old 25th August 2012, 09:49 PM   #26977
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Originally Posted by simon7000 View Post
Now when you talk about noise level that is a broadband measurement. As the ear can has the ability to analyze sound in critical bands, there is the ability to pick out signals 30 db. below the broadband noise level.
There's nothing special about the noise in a dithered A/D/A conversion that would interfere with the ability to hear below broadband. And a properly dithered conversion *completely* maintains all information below the noise floor. What's the point here?

Thanks,
Chris
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Old 25th August 2012, 09:52 PM   #26978
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I don't believe it. Only continuous sine waves can be resolved with just a few bits.
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Old 25th August 2012, 10:15 PM   #26979
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Everyone, I would like to point out that many, many people still do not really like the sound of digital, including me. It has been this way for the past 35 years, at least.
The first digital A-D, D-A that I heard was at Ampex in 1968, and it was 12 bits/50KHz. It sounded edgy. The second demo was a Philips Research Labs, in 1974, and it was 14bits/50KHz. It was better, but not as good as the best analog.
Then, in 1977, the AES had a big debate between 50KHz and 100KHz clock rate, AND we could hear the difference.
Later, Sony, pushed its 44.1KHz, FOR ITS OWN REASONS, and we were stuck with it, starting with the Sony F1 portable digital recording system. We could hear it too, and we tried to 'improve' them, the best that we could. Lots of experimentation at the time.
Then, some psychiatrist found that digital can cause stress. There was a talk and demo at the AES. It almost turned into a riot! Later, I was tested by this psychiatrist, and found him interesting and believable, even though he was rather more 'New Age' than I was. He also tried to use and improve the Sony F1.
Finally, CD was introduced and it was 'Perfect sound, forever!' Yet, it didn't sound exactly right. Papers at the AES were given hoping to improve the situation, phase compensated anti-aliasing filters were developed, and sometimes the CD sounded pretty darn good, yet with other CD's many people found that they could not just sit back and listen for extended periods. Something was still missing.
Later, Sony developed SACD, and others developed 24-96K DVD's and we tried them. PROGRESS! Almost as good as a good analog recording, but not quite.
That is where we are today: SACD and DVD being a superior format, yet in the same sized format as CD. What a deal!
Now, to say that CD is essentially perfect is like liking your daddy's 6 cylinder Chevy, and saying that anything else is unnecessary. '-)

Last edited by john curl; 25th August 2012 at 10:20 PM.
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Old 25th August 2012, 10:29 PM   #26980
SY is offline SY  United States
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Quote:
Originally Posted by john curl View Post
I don't believe it. Only continuous sine waves can be resolved with just a few bits.
That is incorrect. You've been pointed to Werner Ogiers's demonstration before. Look through the telescope!
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