Brad announced his impending demise on his FB page. Since he didn't post it here I didn't subvert his choices.
Which leads to something I was wondering. I dropped out of following DIY for about 18 years and then I came back seemed that everything was a discrete opamp with cascodes and current sources where previously there were none. There does seem to be a kult of komplexity around now with few asking the question if we need it. NP seems to be one of the few voices of reason in this*.
*Note I may have missed other voices of reason and for that I apologise.
well there is a lot of people doing things because they can. Now nothing wrong with chasing PPM distortion for an intellectual challenge but very little evidence there is any good reason for it for audio. Note I am not knocking it, just wondering at what point it started happening and what the real trigger was.
Yo, Scott..
Just read an article on LIGO. It said they correlated the signals with an 8 millisecond delay to accommodate the speed of light between the two detectors.
That makes the detector only sensitive to gravity waves in line with both detectors and only in a tight cone. Is that what they really did? I would expect correlation within a full sphere to be +/- 8 mS.
Is the writeup bogus?
John
Today's blast from the past Crown DC-300 power amplifier | Stereophile.com . Anyone actually measured one of these from 45 years ago?
Complexity for its own sake:
I'm working on a headphone amplifier that runs on 40 volt power supply. With any reasonable headphone load and any reasonable loudness level, the thing will never go into clipping. Never ever ever. Yet I've included circuitry whose only purpose is to make sure the amplifier clips gracefully and exits clipping gracefully. This circuitry also ensures the amp enters slew-rate limiting (~ 120V/us) and exits from slew-rate limiting, gracefully. The diodes and other stuff I used to implement this, amount to 24% of the parts-count of the amplifier (!). Is this "needless complexity"? Opinions may vary.
I'm working on a headphone amplifier that runs on 40 volt power supply. With any reasonable headphone load and any reasonable loudness level, the thing will never go into clipping. Never ever ever. Yet I've included circuitry whose only purpose is to make sure the amplifier clips gracefully and exits clipping gracefully. This circuitry also ensures the amp enters slew-rate limiting (~ 120V/us) and exits from slew-rate limiting, gracefully. The diodes and other stuff I used to implement this, amount to 24% of the parts-count of the amplifier (!). Is this "needless complexity"? Opinions may vary.
Link? I suspect there is a misunderstanding, simultaneous correlation should be equally validating assuming the event has the predicted signature even 4-8ms is a pretty big cone. I can ask but I don't think there is a filter for a particular delay. BTW the spare parts are going to India so there can be some triangulation in the future.
Does this help? https://www.ligo.caltech.edu/image/ligo20160615c
The actual data is available for free download also, https://losc.ligo.org/events/GW151226/
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Sounds like it could amount to needless complexity, for a headphone amp. Although it might be useful for other purposes, maybe just the thing for some application(s).
However, you haven't said why you are doing it. For the sake of complexity itself? Or, for some other reason? Perhaps you find it interesting and challenging? Maybe you hope to learn some new things along the way?
If you are doing it for complexity alone, only 24% possibly unneeded parts count doesn't sound like much. Surely, you can get it up higher than that.
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Found it...
Source:
These 'Waves' May Let Us See the Big Bang's Earliest Moments - NBC News
Quote from article: (hilite mine)
""Once the tunnels were completed, the researchers carefully calibrated each detector, making sure their apparatus would filter out extraneous noise events (including earthquakes, those pothole-hitting trucks, and other ground vibrations). Further, by considering only identical signals observed in each detector, with an 8-millisecond time difference between them (the time it would take a gravitational wave to travel between Washington and Louisiana), all other extraneous sources of noise at each location could be filtered out. ""
This is how bogus info takes off..
edit: yah, that pic shows pretty much what I'd expect.
btw, must be difficult to ship a 4 kilometer long tube...nevermind two..
John
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We smoked a couple of these in 1971 during the intro to "2001" not realizing that the optical film tracks don't have a low frequency limit. Tech HI Fi lent us two and 4 pairs of Bose 901's to set up on the stage in Kresge auditorium.
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btw, must be difficult to ship a 4 kilometer long tube...nevermind two..
John
The detectors and various other mechanical gadgets. The tubes are site built some kind of fantastical continuous fabrication system. Did I mention that a mouse peed on a weld and made a 1u hole that they had to find.
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First off the 16Hz organ note is totally unattenuated, it might even have had a boost. The projectionist told me the optical sound tracks have a lot of nuisance low frequency energy but we ended up blaming the Bose equalizer. Turning 901's around and trying to fill a theater with bass was a stupid idea in the first place. It took 5 min. to reconnect the Voice of the Theaters driven by two Dyna MkIII's at the end of a 70V distribution system. I think the 70V transformers kill a lot of the super low stuff.
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