Absolutely. That is why (despite what some have deduced are my "beliefs" or "sympathies") I don't really automatically discount every claim made, including those that seem to vanish under double-blind testing.
The story goes that Bart Locanthi, many years ago, was asked by Philips to audition some compression schemes and other digital processing. The examples had passed listener panel testing to the satisfaction of the suits.
Bart heard all kinds of problems. He then pointed them out, and when he did the listeners could hear them! But since they had not noticed them initially, suits decided all was well.
Aural evaluation and especially aural memory is rather Janus-faced. It is often construed as a very short-term memory, hence the presentations in double blind are usually rather short (which as well makes the focus, if it ever were to begin with, rapidly shift away from the music, and makes the listening tests just hard work --- a bit akin to serious wine tasting, where you had damn well better spit things out if you expect to preserve any objectivity, lest the "tasting" degenerate into a friendly drunken brawl).
But for many characteristics, those for which the mind-brain has not been trained --- early digital comes to mind --- it may take a long series of exposures before something is noticeable, and longer still before it can be furnished with a vocabulary, let alone that vocabulary making sense to others.
That's fine, but it is not made clear. And most simulators btw assume the initial value as the value at T < 0 (i.e., -1A) and having been on thus "forever". To do something else requires more work setting up the sim. However, with sinusoid,s the generator's T < 0 value is 0.
I'm sure the instructor would have put this in context, and the students knew what the convention was. My point is that it is not specified in the stated problem.
Actually the prior tests would have been with a switch shown and the questions asked about the transient analysis. This is a steady state problem. Of course if a student was confused they would have raised their hand and asked the question.
Now a few shy folks have PM'd me their solutions. So if you are shy feel free except of course for the peanut gallery guys.
The choice of the approximation to a current source (agreeable to me) is eerily reminiscent to the testing and characterization of IV converters in other threads and recent articles
Unfortunately in those cases (not this one) the use of that high of generator resistance obscures mechanisms of distortion that will be present when using real DACs, including code-dependent modulations of said resistance, and distortion due to nonconstant IV converter input impedance.Way too much work. The three digit accuracy answers can be done with a simple calculator and some basic techniques.
Aural memory & training
Very well stated, Brad!
Cheers!
Howie
Howard Hoyt
Dir. of Engineering
AMI, LLC
www.ami-media.com
Very well stated, Brad!
Cheers!Howie
Howard Hoyt
Dir. of Engineering
AMI, LLC
www.ami-media.com
Aha! "Now it can be told". And the switch would have been a shunt one across the generator.
What was your point to posting this?
Avoiding confusing the unwashed! This is presented as a tutorial, your comments certainly expand the scope, but may confuse many here.
Scores have ranged from 8% to 80% so far.
Case in point: I had read accounts of how supposedly lousy digital audio was. Then a housemate's father gave him an early CD player (I think it was a Mitsubishi). My initial impression was What's the complaining about? The excellent time base stability compared to off-center-hole vinyl was the first delightful property to be noted. I went out and bought a bunch of CDs after the first couple.
Then I noticed that I was playing most everything at higher SPL. And as well, listening was turning into, not music listening, but system demonstration. And I started to notice the sessions getting shorter and shorter, and feeling fatigue. One music professor asserted that the problem was the digital audio simply required a bigger power amplifier, that I was doubtless clipping (as usual he was wrong, as he tended to be about nearly everything). I assured him that inspection with an oscilloscope showed no clipping unless the gain was set absurdly high.
The housemate then accused me of having preconceived bias against digital! Although something of a typical composer (who value recordings of their work based on how well they can hear each voice come in, and much less how much the recording sounds realistic), to his credit he did have distinct preferences, if somewhat anomalous ones (he didn't like a MC240 amp, which I had for a while having repaired it for my brother, and preferred the NAD).
Of course the early digital transfers were often done poorly, and from tapes made with an eye to LP mastering (Toole discusses this briefly). And with machines that were themselves problematic. Carver capitalized on this with an early EQ box and one of his cute marketing names, and we inherited this from another music prof, when he found that with a better player he no longer had any use for it. Its "improvement" was spotty and source material dependent.
But of course, everything got better over time (for the most part, with el cheapo and poorly engineered players left out of the sample).
Carver marketing
It is cool what he as able to do with L-R matricies and companded bucket-brigades...although I didn't care for the sound of them. Then again, those gimmicky technologies were aimed at the fat part of the audio market and hit it squarely.
The pseudo-stereo in the TX-11 was a good (or bad in my mind) example of this technology as well. Stupidly many reviewers didn't even notice that the stereo image was faked at low signal levels with this tuner, and merely thought it was just a super tuner. duh.
Another case of missing the forest for the trees due to over-reliance on one's test equipment.
Howie
Howard Hoyt
CE - WXYC-FM 89.3
UNC Chapel Hill, NC
www.wxyc.org
1st on the internet
It is cool what he as able to do with L-R matricies and companded bucket-brigades...although I didn't care for the sound of them. Then again, those gimmicky technologies were aimed at the fat part of the audio market and hit it squarely.
The pseudo-stereo in the TX-11 was a good (or bad in my mind) example of this technology as well. Stupidly many reviewers didn't even notice that the stereo image was faked at low signal levels with this tuner, and merely thought it was just a super tuner. duh.
Another case of missing the forest for the trees due to over-reliance on one's test equipment.Howie
Howard Hoyt
CE - WXYC-FM 89.3
UNC Chapel Hill, NC
www.wxyc.org
1st on the internet
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Reminds me of the L calcs -
This reminds me of the Ls calculations awhile back -- several answeres. Makes me wonder how are we ever going to make realistic sounding music in the home when we cant figure the simple stuff out. maybe because it isnt so simple. maybe it is. ?? -RNM
I would not be that strict. The simplest circuits, analyzed in deep, are in fact the most interesting and revealing
This reminds me of the Ls calculations awhile back -- several answeres. Makes me wonder how are we ever going to make realistic sounding music in the home when we cant figure the simple stuff out. maybe because it isnt so simple. maybe it is. ?? -RNM
I would not be that strict. The simplest circuits, analyzed in deep, are in fact the most interesting and revealing
What physics:
It is a simple differential equation. Pure math.
Edit: however, for those who always point their fingers on schematic following "signal path" it can be confusing, involving some complex physics...
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Bingo!
A trip down memory lane, notice the prices of VCR's and cassette decks. E. Brad Meyer brought this unit to a Boston AES meeting after this article, you could turn the effect up to "11" for some strange sounds.
The Boston Phoenix - Google News Archive Search
I love it! "... sufficiently meaningless to offend no one". And I had forgotten all about the added noise. Too bad it was out (iirc) before the publications on "stochastic resonance" had trickled down into audiophile-land* --- Bob could have exploited those terms for more fancy buzzwords.
EDIT: And even dealers of Harman Kardon equipment still misspelled the name! Harman once got health plan plastic cards for the covered employees. Harman was misspelled. They all had to go back
Although that was not as bad as an ex-office-partner's gaffe, when he and a friend attempted to cash in on Operation Desert Storm, and made commemorative plaques for sale to veterans and others, and didn't have them proofed: they spelled "Cavalry" throughout as Calvary. Oooops.Brad
*Or did they ever?
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