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Here's a question on something I really don't know a thing about:
In this era of hi-rez sound sources like SACD and DVD-A, what's the significance/impact of extended frequency range for/on the perception of speaker sound?
As we know, human hearing is more or limited to below 22 kHz, and so most speaker manufacturers, rationally enough, have been happy to settle with the 20-20,000 Hz range. But a lot of today's premier models are capable of notably good reproduction throughout ranges up to 40 kHz and even 100 kHz, using the newer generation "supertweeters" and other innovative engineering solutions (makers such as Vivid, Gamut, Marten, and Avalon come to my mind). These speakers seem to garner nothing but highest praise in listening tests, especially for their exquisite highs and the impact of these highs on the overall experience of the reproduced sound. Is this reaction simply nothing but a reflection of the great overall engineering job done (flat freq. response way up), or does the hyperextended upper range indeed somehow specifically matter for the way we perceive the sound, even if we can no longer hear it?
That's of course much in the context of SACD and DVD-A recordings whose response exceeds the range of our hearing.
The same question could probably be asked about preamps, too. Why do their range need to extend way beyond the limits of our hearing?
Sorry if this speaks of nothing but blind ignorance on my part.
Follow Ups:
If I remember correctly that study contains, according to Kal Rubinson, who is degreed neuroscientist, methodological flaws.
I've read that paper, can't remember in detail what's in it, did they test the supersonic signal on its own and measured the response?
As for the highest praise in listening tests, keep in mind that probably none of these were done under controlled conditions, so the results are questionable.
Oohashi published two papers on this issue, the first at a 1991 AES convention (no peer review), the second in J. Neurophysiology 2000 (peer-reviewed). In both papers the HF content alone is presented to the subjects and response is measured.
In this respect, the AES paper describes two experiments, one with genuine Gamelan music, the 2nd with simulated Gamelan music, derived from white noise.
In the 1st case, 6 out of 16 subjects responded to the HF signal, in the 2nd case only 2 out of 16. The paper does'nt provide any statistical analysis whatsoever.
The 2000 paper presents the HF results in statistical terms only.
Anyway, I think that such studies are, as interesting as they may be in themselves, of little value to the music lover since hi-rez audio formats appear to have no commercial success.
You are right about the last point...
But the 2000 paper (or am I totally misremembering it from yesterday?) beamed to the subjects the same material thrice: (1) audible range only (below 20 kHz); (2) HF content only (above 20 kHz); and (3) "full range" (both). The response appeared only in case (3), but only in the form of a subliminal physiological reaction and subjective listening preference as gathered from the questionnaire responses. In no case did the subjects report "hearing" any HF content.
I am not convinced that the HF content produced no IM distortion effects in the audible range, and hence, it does not seem to me that ultrasonic hearing is established by Oohashi et al. Kaoru and Shogu used more than two drivers, I think. Also, Kaoru and Shogu showed measurements to determine whether there was any IM distortion produced in the audible range.
"Opposition brings concord. Out of discord comes the fairest harmony."
------Heraclitus of Ephesis (fl. 504-500 BC), trans. Wheelwright.
Just curious, do you know how "detecting" the LF/HF contents in the audio clips was confirmed in their study? Was this detection about "hearing" the signal (the usual way, through ears) or did they use some other form of physiological monitoring?
I couldn't find this paper online except as a $20 download, so I
only read the abstract.
In either case, the possible presence of IM distortion might mean many things or nothing really, but it's hard to say without knowing the test setup and procedure.
I'll send you a copy tomorrow.
...the way we perceive sound is very complex.
When a small change is made at one fequency, it affects our perception of other frequencies, sometimes in the opposite end of the frequency spectrum.
You can experiment with this if you have a speaker with tweeter or supertweeter controls.
This seems to occur even if the added information is outside the normal audible hearing range.
When people add supertweeters, they usually report an increase in sound quality overall including the bass frequencies.
Oohashi, IIRC, a Japanese researcher, presented a paper some years ago showing that adding frequency information above 20KHz increased the subjective listening enjoyment of his test subjects.
Audiophiles report almost EVERY new component they spend their money on increases their sound quality enjoyment. That doesn't mean there's any audible change at all. It just means audiophiles and other humans tend to defend their purchase decisions.
The study you cite proves nothing about "listening enjoyment".
It measures brain activity.
Richard BassNut Greene
Subjective Audiophile 2007
Your objection is about an entirely different issue (psychology of consumer behavior).
This was about human responses to a certain kind of acoustic stimulation. The study was controlled, and clearly shows that in the cases in which there were responses in deepseated (subliminal and autonomous) brain functions (as shown by changes in blood flow and electrical activity), the listeners also subjectively felt something different. And what this "difference" is about we don't really know, but the listeners articulated it as a feeling of personal preference (greater enjoyment, summing up from the questionnaire replies). I thought it was interesting.
What's the troubling part of this? Just curious about your strong reaction.
No one ever said all humans have hearing that goes to 20kHZ. and then NOTHING above is audible no matter how loud.
The unusual "music" chosen was something that few, if any, audiophiles coming here have heard of, or would listen to.
It was chosen for unusually loud high frequency content and may have no correlation with conventional Western music, making the experiment moot for those who don't listen to this particular "music".
You've also fallen into the trap of assuming that when people say they like A better than B, that means they can really hear a difference.
That "logic" skips one important step in the "assumption ladder"
In high end audio, people will say they like A or B between 50% and 75% of the time when A and B are really the same component playing at the same SPL, merely switched off and on to suggest to the listener there are two different components being compared. So what do those "A or B" preferences prove?
Just a quick point or two:
That "music" probably wasn't as "unusual" and weird for the test subjects as it might be for you. (They were Japanese.) You shouldn't get arrogant about your own musical preferences; they are just that, nothing more, even though culturally largely (pre)determined.
And as for "audiophiles," I think to all accounts in Japan you'll be likely to find more of them, and more serious ones, than you do in the U.S. They'd probably think very differently about the suitability of Southeast Asian classical music for audiophile ears.
Moreover, as a footnote one could add that gamelan music has been incorporated into "conventional" Western classical music as well, and wouldn't represent that bizarre an encounter to any friends of Messiaen at least.
"You shouldn't get arrogant about your own musical preferences; they are just that, nothing more, even though culturally largely (pre)determined."
The music for the test was chosen for testing audibility of high frequencies because it had an UNUSUAL amount of high frequency energy.
That could bias the test.
Obviously with louder/more high frequencies, it's more likely the high frequencies would be audible.
As a result, the test results may not correlate to doing the same test using ANY other types of music without an unusual amount of high frequency energy.
My statement was about the music selections used and their potential correlation to any other music without so much high frequency content.
The test music is also unlikely to be in the collections of people visiting this web site, or is likely to be a very small percentage of the music collection.
YOUR decision to call me "arrogant" could only be based on your misunderstanding of the science involved. To choose music with an unusual amount of high frequency energy for a test of high frequency audibility cleary biases a test.
For whatever it's worth, there's quite a bit of extreme-HF energy involved in just about any standard orchestra's playing conventional Western music:
If the point is to measure HF content, you find material that has that HF content (and is not too distracting to the test subjects), simple as that.
Have no intention to insult anyone here, and will simply trust that neither do you, behind the letter of your posts.
... unless you sit four feet directly in front of the trumpet player (you'd get hearing damage if you did) ... so the data have no correlation with what a real person would hear at his seat in an auditorium listening to a real orchestra ... even if he sat in the front row.
Richard BassNut Greene
Subjective Audiophile 2007
I don't know who you are arguing with.
Just to repeat: no one here thinks this line of questioning is directly applicabile to audio engineering in some unproblematic way that has immediate consequences for consumer designs. No one thinks we should all run to the store to buy a supertweeter all of a sudden. And none of this has anything to do with hearing, either, for the n'th time.
The issues are hypothetical and that's where their interest lies. David A. has summarized this intelligently below. For me (and I'm assuming you are interested in my perspective since you seem to believe you are somehow arguing against my take on this), it is the what-if type of questioning that gives the fascinating angle on all this. If moderate LF content enhances listening pleasure, and extreme LF content can induce neuropsychological effects on "listeners" (inaudible subsonic vibration resulting in anxiety reactions in test subjects, etc.), could we then ask whehterhypersonic HF content, too, might have some comparable but maybe qualitatively different effect on the experience of sound perception.
What sort of an effect might that be? What prompted me to think about all this in the first place (in the context of hi-rez audio) was the uniformly positive response that some new speaker designs utilizing "supertweeters" have been met with in listening tests; a response moreover that seems to steer away from the banal "liquid midrange" and "smooth highs" discourse in describing the listener reactions. The auditing experience is usually summarized with the rather simple bottom line as being "very, very nice" in some hard-to-pin-down kind of a way (the point being about noteworty presence of subjective listening pleasure). What if in some way it's about the HF content that these models can reproduce?
Whether this hypothetical effect has anything to do with IM distortion is another matter. If it does, what would happen if through design solutions this distortion could be eliminated? Would the effect then be equally or even more pronounced? Or is it precisely IM distortion that causes this response in the subjects in the first place - in which case we could maybe conclude that here we have yet another possibility for euphonic solutions in sound reproduction devices? Or is the whole IM distorion issue something that exists apart of the engineering matrix, as some general property of soundwave behavior in the atmosphere? (In which case it would be interesting to consider why we have the perceptive capability for it somehow built into the design of our anthropological apparatus.)
The more directly consequential questions for someone thinking of a speaker upgrade lie obviously elsewhere, most immediately in things like the accuracy of frequency response within the audible range, lack of coloration & distortion, and good interaction with the environment in which the system is set up. Without these you will have no satisfying sonic experiences whatsoever.
It's important however to remain open to questions and have some fun in the process even if the issues seem purely speculative at present. Who knows, maybe tomorrow they are a feature you can choose for your system setup, too. Obstinacy combined with a single-issue mindset is never a good thing to have, and we all know we have enough of ideology and dogmatism in this field already (for the record, I'm not claiming these are what you stand for). Why not be open-minded and exploratory? The research problem in the study was intriguing, pregnant with implications, and it certainly merits further consideration.
But enough of this already.
I have no idea why you are debating me over mkuller's post saying that supertweeters get good reviews from their owners and also claiming a Japanese study could explain why.
I responded that most people defend their purchase decisions -- it's human nature -- so that doesn't mean much.
I also added the study was biased and NEVER even tried to prove the listeners could hear a difference between the music with, and music without, frequencies over 22kHz.
The study leaders were too eager to accept subjective "preferences" (non-science) without testing to see if the listeners could hear any difference under blind conditions (real science).
The study has very little connection with the audibility of adding supertweeters.
I rest my case.
Please let mkuller defend himself in the future.
Richard BassNut Greene
Subjective Audiophile 2007
Assuming that's true, does anyone know what this effect is based on, since we really can't hear that part of the bandwidth?
Those make for a good read. I think this is an interesting subject that has obvious and important implications for speaker design. The evidence, at least in these well-referenced and to all accounts solid research papers, seems indeed to indicate that inclusion of above-22kHz high frequency information in the audible bandwith, even when imperceptible as such, produces neurophysiological responses in the brain and a psychological effect in the listener that amounts to a subtle sensation of pleasure and subjective satisfaction - in other words, perhaps the listener happiness that we all strive for through all that gizmo swapping and system tweaking upstream?
That would also explain why the sound of the speaker models I mentioned is found extraordinarily pleasing in prolonged listening tests, whereas for example some studio monitors (which usually stay within the sub-22kHz range) appear "detached" and subjectively "uninvolving" even when their respective performance capabilities would otherwise be equally or more impressive in key respects and based on superior engineering solutions. (I know, there are just too many other variables involved, too.)
Thanks for responding.
...for an explanation.
Participants never proved they could hear a difference.
They merely voted on which version of the Bali "music" they preferred.
That proves absolutely nothing.
Random guessing could easily lead to people preferring either A or B
People will choose A or B because they are trying to please the experiment leader -- rather than saying "I don't know", or "I can't hear a difference". True of high end audio too!
The psychological assessment was just one (and subordinate, sort of control) part of it. What correlated with it (and took priority over it in the evaluation) was two other things: an EEG analysis and a PET measurement in each case. The subjects didn't need to hear any difference and it was even assumed they wouldn't; their bodies registered the variations subliminally, and the structured interview questions confirmed that they indeed had also sensed or perceived (not heard, since this was all ultrasonics) something.
The study seems important in the field - even at a superficial look around you can see that it's frequently cited in serious studies and by serious people whom I think you, too, would recognize as an authority.
I think you just have a big bass bias!
If I remember correctly, some time ago I have done a search in the Science Citation Index and could not find any paper that cites the Oohashi papers, other than Oohashi himself. I can do that search again next week just to check.
Hi Klaus,
I need to do a better check: for now I just ran a quick Google search and found citations by people such as David Griesinger (of Lexicon), James Boyk (director of Cal Tech music lab and lecturer in its dept. of electrical engineering), and a bunch of faculty at psychology, music, and various tech depts. around the States(Berkeley etc.). Plus a co-authored piece in an audio engineering journal in Germany (which I can't recall now). These were all references that seemed to take the Oohashi et al. paper seriously. And then of course the references in Stereophile and other audio fora.
From my quick search I was not able to find any refutations of either the hypotheses or the research procedure, though that may be because the research questions simply haven't been adequately put to test yet. (Meaning it's just too hard to evaluate, apart from the test setup and methodology, but even they seemed fine at a quick glance.) What seemed to be a novelty in the Oohashi 2000 paper is that the audio clips were longer, as were the pauses in between them; the assumption being that certain physiological responses only become manifest rather slowly (compared to the usual few seconds done in audio tests) and have a correspondingly slower settling time afterwards (have a hang time).
I would think J of Neurophysiology must be quite a respectable publication in the field (of which I know nothing to be sure). There was moreover another paper by Oohashi in 2006 in Elsevier's Brain Research journal, 16 February 2006, in which the conclusions are that this HF effect with a bearing on listening preferences and manifest in brain function responses may not have anything to do with "the conventional air-conducting auditory system," since this effect was manifest "only when the listener's entire body surface was exposed to High Frequency Components, but not when HFC was presented exclusively to the air-conducting auditory system." (They used a loudspeakers vs. headphones type of a setup.)
Oohashi himself has a nice career behind him (from Wikipedia - ):
"He held positions such as Instructor at Tsukuba University, Professor at the National Institute of Multimedia Education, Professor at Chiba Institute of Technology, and General manager at the Department of KANSEI Brain Science, ATR Human Information Processing Research Laboratories. He is the President of the Yamashiro Institute of Science and Culture and the Director and chief researcher of the Foundation for the Advancement of International Science."
I just find this quite intriguing as a hypothetical issue. Not sure what the repercussions would be for audio design; there are just too many variables involved, even if Oohashi & co. are right. (The research reported in the J Neurophysiology issue was based on double blind testing and the results were statistically significant.)
More stuff to read, that is. What's your take on all this?
"I need to do a better check: for now I just ran a quick Google search and found citations by people such as David Griesinger (of Lexicon), James Boyk (director of Cal Tech music lab and lecturer in its dept. of electrical engineering), and a bunch of faculty at psychology, music, and various tech depts. around the States(Berkeley etc.). Plus a co-authored piece in an audio engineering journal in Germany (which I can't recall now). These were all references that seemed to take the Oohashi et al. paper seriously. And then of course the references in Stereophile and other audio fora."
These are not the type of references that lend credibility to a study. These references are merely using the results/conclusions of the study to support or interpret their own interests and phenomena. What is singularly lacking is any independent duplication and confirmation of Oohashi's work. That does not mean it is wrong but, rather, that it is unconfirmed and no other competent neurophysiologists seem excited enough to do so.
"I would think J of Neurophysiology must be quite a respectable publication in the field (of which I know nothing to be sure). There was moreover another paper by Oohashi in 2006 in Elsevier's Brain Research journal, 16 February 2006, in which the conclusions are that this HF effect with a bearing on listening preferences and manifest in brain function responses may not have anything to do with "the conventional air-conducting auditory system," since this effect was manifest "only when the listener's entire body surface was exposed to High Frequency Components, but not when HFC was presented exclusively to the air-conducting auditory system." (They used a loudspeakers vs. headphones type of a setup.)"
This seems to be consistent with the strange results of Oohashi's localization of brain responses to regions which are, to a great degree, not generally associated with audition.
Instead of ripping apart a series of unduplicated reports, I'd rather regard them as intriguing and await independent confirmation.
Sure, except in your point that these authors are "merely using the results/conclusions of the study to support or interpret their own interests and phenomena." I think that would be hard to prove, and it's not exactly the kind of activity these people (Griesinger, Boyk & co.) are known for in the audio engineering circles (unless you are referring to those folks at Stereophile). We can safely say that at least those named are more scientifically oriented in their methods and approach than the great majority of those earning a living from audio industry out there. Moreover none of those I mentioned, as I think I stated, framed the findings of Oohashi et al. in any way; they merely observed the existence of this research and its results, calling attention to the broader issues it too addresses. Sort of tossing it in the air and asking: What do we make of this?
So I'd say that's a bit biased as a statement from you.
Nope. None of these people, although respected and respectable in their own fields they may be, are neurophysiologists. Since they cannot replicate these or similar experiments, their use of the results does not constitute confirmation of the findings. When one looks at citations, those of reputable scientists in the same field are significantly different from those from outside the field. So, no disrespect for these people was implied.
OTOH, I have yet to stumble on any references to Oohashi's work in the neurophysiological literature. The latter would be of interest to me.
Not to be splitting hairs, but your initial claim was that they are "merely using the results/conclusions of the study to support or interpret their own interests or phenomena." That's a positive statement: it's basically claiming that they *are exploiting* the study for their own purposes. That's a very different claim than your current negative statement that "their use of the results does not constitute confirmation of the findings," which proposes that they *are not validating* the study.
The thrust of these two statements is very different in each case. I wouldn't disagree with the latter but I'm frankly puzzled by the former.
Without taking a stance on the merits of the paper (apart from my fascination with its research problematic), I haven't found anyone either criticizing its procedure or repudiating its results (apart from these very pages, that is). Since in accordance with all basic principles of scientific method the paper is very open in recording the details of its test setup and procedure, in principle anyone can also verify its basic correctness and assess its fundamental flaws. Instead of vague hints about lack of response in one academic corner (but not in some others) constituting a de facto refutation, why not break the silence and tell what's wrong with it, anyone? The floor is open and the audience is waiting and I am already busy making notes.
You're interested in seeing a credible confirmation, I'm interested in seeing a credible refutation; at some point we must compare notes.
I think you are splitting hairs. The reference and use of the conclusions of a scientific publication is fair game for anyone. For these audio technologists to do so is perfectly reasonable and I did not imply any misuse on their part.
As for the second issue, the lack of any scientific interest in this subject is, especially in the face of Oohashi's publications, to me, telling. It is suprising that it did not stimulate any interest in the field of auditory or sensory neurophysiology.
I have not read the paper carefully in quite a while but I recall that my procedural objections (and surprise at some of the results) do not invalidate the paper. They only prevented me from accepting it fully until there is some independent confirmation.
"You're interested in seeing a credible confirmation, I'm interested in seeing a credible refutation;" Frankly, I'd welcome either.
Would you have the bibliographic references of the papers you've found?
My take on this is that it is of academic interest for those who listen to low-rez formats only. For those who fancy hi-rez these findings may have some value but then, without electronic x-overs and having the supersonic stuff in a separate channel you probably are listening to IM distortion. So are audio press and manufacturers selling misinformation, once again ? What about tests with western music and western listeners?
I would think the same (your point 1). Except that vinyl is not really (as) low-rez (as PCM). Doesn't it rather depend on contingent capabilities and properties of the vinyl rig what it can reproduce out of the analog source?
TIA for the Kaoru & Shogu paper. It could offer more fodder for thought on the significance of IM distortion in this respect (your point 2).
These won't qualify as adequate referencing but here we go:
- I stumbled upon a German tonmeister thesis work that I didn't read yet (bet your German is faster - ) but which seems relevant at least in parts. I got interested b/c of the two supervisors (Maillard and Meyer) who are pretty much the creme de la creme of the current-generation tonmeisters around.
- Griesinger's "Perception of mid frequency and high frequency intermodulation distortion in loudspeakers, and its relationship to high-definition audio" is a PPt presentation (at AES 2003 meeting) and I'll email it to you. Found ref to it in a NHK Labs paper by Nishiguchi at
Similarly only skimmed through a few pages so far. He is high credibility in the audio world as I understand it.
- The Boyk piece (mosty spectral analyses) I mentioned, "There's Life Above 20 Kilohertz! A Survey of Musical Instrument Spectra to 102.4 KHz," is at http://www.cco.caltech.edu/~boyk/spectra/spectra.htm.
Oohashi et al. are mentioned rather in passing in the (too) short discussion on significance. I couldn't find anything else by him, so I just wonder.
- And an item from HiFi News with some more references at the end (though none of these are very recent
No idea who this author is.
- Stereophile had a big editorial and discussion on this stuff at the early days of SACD & DVD-A, in 2000 or 2001 I recall (try searching "Atkinson Boyk").
- Best of all, I just realized that we may be rehashing a old debate from these very pages: see http://www.audioasylum.com/audio/general/messages/129397.html...
So it seems it's by no means a new discussion, even if nothing has really been established in the meantime. Indeed, why hasn't anyone done further studies on this?
If you want to test for audibility of sound above 20kHz. then you use test signals ONLY above 20kHz.
At best the study might prove that human hearing does not have a "brick wall filter" at 20kHz. But we already knew this.
If someone here wants to use a study to prove super tweeters are good components (for people who visit here), then he should cite a study using supertweeters playing ordinary Western music, not some bizarre "music" that contains an unusual amount of high frequencies, and then using brain measurements as a proxy for audibility.
Richard BassNut Greene
Subjective Audiophile 2007
Don't you think, RBNG, that brain scans would be better indicators of whether a difference was detected or not than asking someone, which can be full of bias from that listener?
Why shouldn't the authors start with the most favorable conditions first? This is a normal way to evaluate a hypothesis in any case.
The brain has a huge number of inputs, many of which are not noticed because they are masked by stronger simultaneous inputs. I think brain scans would not correlate with subjective sound quality.
If a blind listener, or listening panel, prefers the stereo system sound quality when a supertweeter is connected, versus when it is not connected, then you have a useful experiment to support buying that super tweeter for that stereo system.
We don't need brain scans ... and specially selected Indonesian music ... and only listeners under 35 years-old (whose hearing was never tested). That's too far removed from our reality to be a meaningful test.
"If you want to test for audibility of sound above 20kHz. then you use test signals ONLY above 20kHz."
Do you? There are 2 issues here. The first is whether or not we can hear pure toned above 20 kHz. For that, you test with signals only above that frequency. The second is whether HF content above 20 kHz affects what we hear below 20 kHz. For that you test with broad band signals as they did in this test.
"At best the study might prove that human hearing does not have a "brick wall filter" at 20kHz. But we already knew this."
Do we know this? How many people do you see here and elsewhere saying that we don't hear anything above 20 kHz and suggesting that supertweeters should therefore be inaudible. Many people believe "can't hear anything above 20 kHz" equates to saying we have a brick wall filter there. There's quite a deal of variation in what audiophiles appear to believe about this point based on what gets said here and elsewhere.
"If someone here wants to use a study to prove super tweeters are good components (for people who visit here), then he should cite a study using supertweeters playing ordinary Western music, not some bizarre "music" that contains an unusual amount of high frequencies, and then using brain measurements as a proxy for audibility."
I think you're wrong. We use test signals for determining what people can hear in the accepted audible range rather than "ordinary Western music" or speech, so why not use signals other than those for tests like this. What you want for test material is sounds with a lot of HF content and you'd probably want to vary the content below 20 kHz in order to determine whether frequency content below there affected how we respond to frequency content above there. The frequency distribution of sounds in Western music and in other musics such as gamelan music varies and there's no reason why Western music should be a more suitable 'test signal' than gamelan music. Since the study was done by Asian researchers, it's probably not surprising that they chose non-Western music for their tests. Western researchers are quite free to duplicate the study using Western music and that would probably be a good idea.
As for using brain measurements as a proxy, this does produce 2 useful results. First it removes the subjective response issue that would be present if the researchers only asked the subjects questions about what they thought they heard. You criticised such approaches quite strongly in your original "Dumb Study" post when you said "People will choose A or B because they are trying to please the experiment leader -- rather than saying "I don't know", or "I can't hear a difference". True of high end audio too!". Second, it relies on an objective physical measurement that the subject can't control so it produces quantifiable data which is always a plus in any study.
It does leave us with a problem about whether or not we wish to say that the person "hears" the hf content above 20 kHz if they don't report hearing anything when presented only with sounds above that frequency.
What we are left to deal with, if the results are repeatable and accepted, are a number of questions like:
- does the fact that we respond to hf content extending above 20 kHz affect our perception of that portion of the sound below 20 kHz? About all we can do hear is question the subjects and see whether they have any sort of repeatable, consistent response to sounds with extended hf content that is not present when they are presented with sounds with the above 20 kHz content filtered out.
- do people prefer sounds with or without such extended hf content.
To answer both those questions we're going to be forced to rely on the subjects' subjective responses to questions about their experience, but at least there can be available the objective data of each individual's brain responses as well and it may prove possible to correlate some of the subjective responses to particular aspects of the brain response.
There are probably some very good grounds for criticising this study, but I don't think your points here are among them.
There are many complaints about FM radio sound quality.
But complaints about output above 15kHz. seem rare.
When listening to typical Western music on FM radio, it seems that the
tiny amount of sound energy above 15Hz., assuming there is any,
can be eliminated and few people, if any, complain about its absense.
It seems to me that the people in the test said they preferred the music with content above 20kHz. WITHOUT ever proving they could hear a difference the two samples. A blind preference selection without the needed audibility test, is a typical high-end audio "blind test" (but not really a test at all).
There is also a possible question about how the energy above 20kHz was stripped from the music, and whether doing so created an audible artifact.
"There are many complaints about FM radio sound quality.
But complaints about output above 15kHz. seem rare."
What's to complain about? There basically isn't any :-)
Sorry, but you started out with this throwaway line and then threw it away anyway with your next sentence, so I couldn't resist this response.
"When listening to typical Western music on FM radio, it seems that the
tiny amount of sound energy above 15Hz., assuming there is any,
can be eliminated and few people, if any, complain about its absense."
You're right, but is that because our expectations of the quality of sound from FM radio are less than our expectations for quality from other sources? I enjoy listening to FM and I think it does a good job of doing what it does, but I wouldn't compare its sound quality to CD or vinyl. I listen to the radio for different reasons to those that I listen to my audio system for, and I both expect different things and accept a lower sound quality. I suspect most people concerned with sound quality are similar, even those who want to extract the most from FM as a source and who buy expensive tuners and antennae in order to get the most from it. I don't think your point here proves anything that helps your argument.
"It seems to me that the people in the test said they preferred the music with content above 20kHz. WITHOUT ever proving they could hear a difference the two samples. ""A blind preference selection without the needed audibility test, is a typical high-end audio "blind test" (but not really a test at all)."
It seems to me, from reading the table of the subjective results, that overall they thought that there was a difference on 5 parameters but that there was also not a significant difference in their like/dislike responses. The comment about preferring the sound with HF content is made in the text of the report but it did not seem to me to be borne out by the table of subjective results. That aspect of the report disturbed me. I think the authors assumed that if the subjects thought that the sound with hf content was perceived as "better" on those 5 parameters for which there was a significant difference, then the subjects preferred the sound with hf content. I don't think there was a strong preference for it because, if there was, then there would have been a statistically significant difference on the like/dislike parameter and there was not.
"A blind preference selection without the needed audibility test, is a typical high-end audio "blind test" (but not really a test at all)."
For a start we have the brain scans to show that there was a different response to the sounds with and without the high frequency content. There is also a statistically significant difference in subjective reports on 5 parameters. Audibility tests rely on the subject stating whether or not they hear the sound and that is a subjective report also. Determination of whether or not a sound is audible is done by whether or not there is a statistically significant response from a group of subjects, just as the determination of whether or not there were differences in the sound was made here. I think this is a valid test, but just because the test design is valid does not mean the results are valid. I think replication would be very good, especially replication with a variety of different sound types, before we started hanging too much on the results.
I'd also say that a "blind preference test", to use your terms (and I don't think the parameters on which there were significant differences in perceptions of the sound were preferences�I think the one parameter that did relate to preference failed to show a significant difference in perception) is valid. If people display a consistent and statistically significant preference for sound with hf content over sound without it, or vice versa, in a blind test, then it's plausible to believe that there is some attribute to the preferred sound that is linked to the preference. Whether or not that attribute is audible in isolation, ie the hf content on its own, is irrelevant. People may not be able to hear the hf content on its own but it may modify the way in which sound below the hf frequencies are perceived.
"There is also a possible question about how the energy above 20kHz was stripped from the music, and whether doing so created an audible artifact."
Agreed�that is an issue to be concerned about.
There are issues with this study which deserve further attention, and I'd love to see it replicated a few times with a wider variety of subjects and sound types before I hung too much on the results, but it is a much better quality study than you seem to believe.
The many test biases to "encourage" high frequency audibility:
-All the subjects were under 35 years old.
-Many were women.
-The Indonesian music had an unusual amount of high frequencies.
-Brain measurements were considered a proxy for "hearing"
-No one had to prove he/she could really hear a difference before stating a preference for music with and without the ultra high frequencies. (Beyond that complaint, the subjective evaluation conclusion didn't seem to follow from the data -- you covered that well in your post)
I just don't see how this study could support a decision to buy a super tweeter.
I mentioned FM radio in my prior post because there are no frequencies over 15kHz. ... meaning that a small amount of sound energy is eliminated for broadcasta (this didn't read as clearly as it should have) ... yet that fact NEVER seems to be mentioned among the many complaints about FM radio sound quality (even complaints by golden ears who think every wire sounds different).
The best sound quality I have ever heard from a stereo was from a Redbook CD with no output over 20kHz. But then I can't hear 15kHz. anymore!
Richard BassNut Greene
Subjective Audiophile 2007
That's a serious question.
IF (note: big "if") you want to find out whether HF content can be perceived by listeners in some way (note: I did not say 'heard' for reasons I will state a little later), then I think as an initial test it is more than reasonable to start with subjects who are under 35 and largely female, and with music with a high HF content, because if you can't get a positive result under those circumstances you would seriously need to consider giving up on the hypothesis. If you get a positive result under those circumstances, then you could be encouraged to continue with a wider range of test subjects including strong representation from older people and males, and with music with less HF content to see just how perceivable the HF content is for a wider and more representative set of subjects and with a wider range of music if, of course, you were interested in the question from a musical enjoyment angle rather than a straight perception angle which I'm not certain the researchers are. I think it's actually worth while starting out by seeing whether people who are most sensitive to higher frequencies in sound show a response than by starting out with a sample of people who are less sensitive to higher frequencies or even with a group of people representative of the population as a whole. I'd rather establish that some "more sensitive" people show a response and then see just how representative their response is than come up with a negative result from a less sensitive group that leads to the question being dropped and ending up not knowing that some people do show responses.
Now, as to "hearing". Our various senses register a wide range of stimuli including, in total, a much wider band of the radiation spectrum than any single sense registers. We can feel low frequency sound if the volume is high enough, and we can feel subsonic frequencies that we can't 'hear'. Does that feeling aspect of low frequency perception affect our experience of the low frequency sound that we hear, and does it affect our enjoyment of that sound? Under some conditions, I think it does. I like the vibratory effect I've perceived with bowed double bass sounds at time, and it adds to my enjoyment of the auditory aspect of the sound. Testing has failed to show that people can hear pure tones much above 20 kHz, and that we lose the ability to hear the last 5 kHz or so of that with increasing age. Does that mean that frequencies above 20 kHz don't contribute to our perception of sound? Not necessarily. What if frequencies above that are perceived by one of our other senses, as subsonic frequencies can be perceived? If that is the case, does such perception modify our overall perception of sound containing HF content in its overtone structure? That's a hard set of questions to answer but they are worth asking.
What this study attempts to do is to ascertain whether there is a difference in perceptual response to sounds containing HF content to similar sounds with the HF content filtered out. The brain measures are a good, objective means of determining whether there is a difference in response and this study indicates that there were differences. That's a good starting point but there are a lot of things that need to be sorted out before one can know what that really means. Amongst those things that need to be sorted out are:
- whether this study can be replicated with different subjects from the same demographic (ie under 35, largely female) with similar test signals. The reason for that is simply that this is the starting point and if there was some problem with this study that threw up a false positive result, it would be nice to find that out early;
- next, if replication is possible, what happens when the demographics of the test group are changed to a more representative sample? How do age and gender affect the results?
- next, vary the test signals with different sounds and music to determine how the proportion and nature of the HF content affects the results.
- and somewhere in the process, start trying to find out just what mechanisms are involved in the perception of the HF content. Is it hearing or some other sense.
- finally, at least as far as science is probably concerned but hopefully a little earlier for those of us with more personal interests in this particular question, is resolving the issue of whether such perception�once we're genuinely satisfied that it is present�modifies our enjoyment of music and in which ways does it do so.
I reckon this is a damn good study for an initial foray into an extremely interesting area. It doesn't answer all of the questions, and it raises a few of its own, but at least it gives some good strong support to a push for further investigation into the area and I think that's a very good thing. I think it was worth doing the study and I think it was worth publishing the results as they are because that may well encourage others to look at the topic and that's essential to the process of finding out a bit more about it.
As for your final comments on FM quality and sound quality in general. I don't know whether the best sound quality I've heard is from CD or from vinyl because I've heard damn good sound from both and we know vinyl does contain higher frequencies than CDs do. I quite enjoy FM radio from time to time. I'm also 60 this year and, though I haven't had my hearing tested in years, I do know that I can't hear a 15 kHz test tone on my system at the levels at which I normally listen to music. I also know that I prefer the sound of CDs on my system (no vinyl source in my system) to the sound of FM radio. Is that because CDs contain higher frequency content than FM�content at frequencies that I know I can't "hear", because my CD player is of better quality than my FM receiver, for some other reason, or for a combination of 2 or more of those reasons? I don't know the answer to those questions and I'd venture to suggest that neither do you. At least this study is a first step to answering some of those questions and it's nice to see that step taken.
I'm not unaware of problems with this study but I'd rather appreciate it for what it does than rubbish it because I don't like its shortcomings and/or have severe doubts about what it sets out to prove. I think the researchers deserve a fair bit of credit for their work on this one.
I think the study provides evidence that there is no logical reason to limit frequency response of any recording medium to 20kHz., even if no one could hear above 20kHz.
Unlike bass frequencies, treble over 20kHz. is:
(1) Not felt by the body
(2) Absorbed faily well by air in the room, and
(3) Easily masked by much higher music energy levels at other frequencies.
As soon as I noticed that the study used unusual music that contained an unusual amount of high frequency energy, I suspected the study leaders had an agenda.
Richard BassNut Greene
Subjective Audiophile 2007
"They are if the study is to correlate with people visiting this website and the typical music they listen to"
To paraphrase Carly Simon, "You're so vain, you probably think this study is about you".
Why should this study correlate with people visiting here and the music they listen to? For a start, science is rarely concerned with audiophiles and music lovers. We benefit from quite a bit of scientific research but that's a happy accident. I doubt Oohashi and his fellow authors have even heard of us, and that doesn't detract from the study one bit.
I think that really drags this thread to an end.
Give me a $#@%&$@ break!
Richard BassNut Greene
Subjective Audiophile 2007
Give you a break because the study results were used by someone here to support the purchase of supertweeters by someone else here!
I'd be happy to give you a break if it weren't for one thing. Your first post was entitled "Dumb Study" and simply rubbished and, in my view, misrepresented some aspects of the study. I said I didn't think the study was so bad but all you've done since then is to try to trash it even further. You didn't about the use others made of the study at any time. You simply trashed the study at every opportunity.
I'd be happy to give you the break you asked for, for the reasons you want it but regardless of what others have said in this thread, my debate with you has never been about whether or not the study could be used to support the purchase of supertweeters. It's been about the general worth of the study, as a scientific study, right from my first response to you.
"IF (note: big "if") you want to find out whether HF content can be perceived by listeners in some way (note: I did not say 'heard' for reasons I will state a little later), then I think as an initial test it is more than reasonable to start with subjects who are under 35 and largely female, and with music with a high HF content, because if you can't get a positive result under those circumstances you would seriously need to consider giving up on the hypothesis."
This is simply starting at one extreme of possibilities to give the "best case" set of conditions. I see nothing scientifically invalid at all with those and I am not sure why RBNG thinks these are biases.
It also seems to me that brain activity is a much better indicator of whether someone heard a difference than simply asking them, which can be full of bias. Involuntary responses are most likely more accurate indicators.
As to FM, I am not sure why RBNG decided to muddy the waters with this comment. Since no one has ever heard FM with content ABOVE 15Khz then who is to say whether people would like it better or worse than with that content? Most people prefer cd or lp to FM radio in a high res system, is this because of more HF content?? Who knows.
Thanks for bothering to sum it all up.
Oohashi & co. did another study in 2006 in which their findings seem to suggest that this HF content perception "occurs" not through the auditory ear mechanism (air pressure through ear canal etc.) but through some other mechanism, as you surmise yourself, too. When listening was done through high-isolation earphones, no such "hypersonic effect" was shown. When the whole body of the listener was exposed to the signal (through loudspeakers), the effect was there.
For some time already there have been speculations (and more serious studies perhaps too) regarding perception of sound through bone conduction.
Of course....
No one can prove anything.........
Chasing after "proof" in audio is a complete fools errand, - but I know someone around here who speaks so authoritatively, - one would think that he thinks that he's the most humble man that's ever walked the earth.... Heaven forbid that he actually goes out and gets some experience. But deep runs the fear of the man who is exposed with his pants around his ankles...
The problem of leisure, what to do for pleasure. Ideal love a new purchase, a market of the senses. Dream of the perfect life.
Richard BassNut Greene
Subjective Audiophile 2007
Well, hearing ultrasonic frequencies is controversial, to say the least. It takes more than just the signal being present and people being able to detect a difference. What seems to happen is that when when the ultrasonic frequencies can intermodulate with other frequencies in the speaker driver and produce intermodulation distortion (difference tones) in the audible range.
-Audio Engineering Society Convention Paper 5401, presented at the 110th Convention, 2001 May 12-15, Amsterdam, The Netherlands:
"Detection threshold for tones above 22 kHz," by Ashihara Kaoru and Kiryu Shogo, National Institute of Advanced Industrial Science and Technology 1-1-4 Umezono Tsukuba, Ibaraki 305-8568, Japan.
"Opposition brings concord. Out of discord comes the fairest harmony."
------Heraclitus of Ephesis (fl. 504-500 BC), trans. Wheelwright.
It seems as if the Oohashi studies are ok in this respect since they have used bi-channel systems with filter set at 26 kHz (170 dB/octave). However, audio systems as they are used in reviews and homes don't have electronic x-overs and multiamping. So, once again, the results obtained in listening tests using such systems are questionable, at best.
I am not at all certain Oohashi was able to remove the IM distortion, although they did make an effort. They say they eliminated the IM between the high frequency content and the lower frequency contentn by using two drivers. But since the IM would be difference tones, the tones in the speaker used for the high frequency content could very well have produced IM distortion products in the audible range. Measurements could have shown whether there were or not. Kaoru and Shogu showed graphs showing very clearly whether the IM products were present or not.
"Opposition brings concord. Out of discord comes the fairest harmony."
------Heraclitus of Ephesis (fl. 504-500 BC), trans. Wheelwright.
Good research work Pat D
Richard BassNut Greene
Subjective Audiophile 2007
My best guess is that the behavior of the frequencies you can hear is actually changed by the presence of other frequencies. This is demonstrable at the other end of the spectrum. While ultrasonic high frequencies cause people to report improved midrange and sometimes improved bass, properly integrated infrasonic low bass seems to cause many to report improved midgrange and treble. In that case, since small waves ride big ones, assuming there is low frequency information in the recording, the presence or absence of those extreme frequencies, whether audible or not, will change the behavior of the sounds you CAN hear. As to whether the tiny ultrasonic waves will modify the bigger waves they sit on in a relevant way, I can't be sure. Haven't played with supertweeters much. But if it works for (good) subwoofers, it's probably true at the other end as well.
I thought the cutting head for LPs was 65khz? So ultra sonics have been with us for sometime.I dont know if its the ultrasonics that make these hifrequincy transducers sound good but it could be that many tweeters are rolling off in the frequincy ranges that humans still hear and the extended trebile that ultrasonic designs brings to the table is just extending this range. I find super tweeters etc to add a wee bit more air but if they are running in frequincys that humans hear they add more trebile energy.
So, in other words, ruler flat response to the hearing limit (and beyond) is what makes it sound "better," or distinctly "airy," "delicate," "spacious," "refined"?
I know it's possible to sense subsonic frequencies (you can even use them for torture or for creating panic, uncontrollable anxiety, and the like), but I just don't know if the same is true about ultrasonic frequencies and if so, whehter the effect then would be the reverse (inducing happiness in the "hearer"...).
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text:
The Fool FAQ
I'm totally new to this whole thing, could you possibly give an example of how bonds work?
When you buy a bond, you are actually loaning your money to the organization that issued the bond. That is why bonds are often called "debt instruments." The principal (the "face value" of the bond) is repaid on the maturity date. In the meantime, you are paid a set amount of interest, usually every six months. This interest is called the "coupon" or "coupon rate." It's called that because bonds used to come with little coupons attached that you would cut off and send in twice a year to receive the interest payment. How quaint. Nowadays, the coupon rate is nothing more than the annual interest rate.
When bonds are originally issued they are issued in even denominations, usually $1,000 and occasionally $5,000, with some government bonds at $10,000.
Let's look at how bonds are described. For example, you could buy a New York State G.O. (Government obligation) with a maturity of 5-1-06 and a coupon of 5.25% priced at $96.425. Now, before we get confused, let's look at each of those components.
Maturity = the day that you get all of your original investment back. In this case, you would get back $1,000 per bond on May 1, 2006.
Coupon of 5.25% = This is the annual interest rate. Every six months you will receive an interest payment on your initial investment. This payment will be equal to the coupon rate (divided by 2 since each payment is for only half a year) times the denomination of the bond. So in this case you will receive $26.25 ($1,000 x .0525/2) every six months. In the case of tax-free bonds, the interest is tax-free.
Priced at $96.425 = All bonds are priced in units of $100 even though you can't buy them for that. Our example is the most common kind of bond -- a $1,000 denomination. This bond is selling at a discount to its original price. If a $1,000 bond is priced at 96.425, then your price per bond will be $964.25, not $1,000.00. The original price was $100.00 (meaning that it actually sold for $1,000), but once a bond enters the secondary market (you can buy and sell them at any time), the price fluctuates based on how the bond compares to the terms that new bonds are being offered under. This bond's coupon rate is lower than the current interest rate for a comparable newly issued bond, so it is selling for less than its original value.
Bond pricing gets complicated so hold on...
Say you have an old 20-year bond that expires in 5 years and has a coupon interest rate of 10%. Wow. New 5-year bonds are only paying 5%, so obviously your bond is worth more -- the question is, what price would someone pay for your bond with its premium interest rate? Well, the market tells us that people are willing to pay $1,000 for a 5-year bond that pays them $50 a year in interest, but your bond pays $100 a year in interest, so you might think that someone would be willing to pay a lot more for it, based on the interest it pays. That's true, but there are other factors -- both bonds pay $1,000 in cash at the end of 5 years -- so maybe the price should be the same. Then you have to look at the entities that issued the bonds -- are they equally likely to still be in business and be able to repay the bond's principal?
There is a complicated formula that takes into account the length of time to maturity, the coupon rate vs. the current equivalent interest rate, the relative possibility of default between the two issuing companies, and comes up with a price for your bond that is supposed to make it the equivalent of a newly issued, comparable bond. Oh, if you have something called a 'bearer bond', which means that the issuer of the bond doesn't have your name on the certificate, make sure that you register them in order to get your interest and to be notified of any changes.
Wow, there's a lot to bonds. Are there any books I can read about them to learn more?
Here are two books you may want to look at. The first is The Bond Book by Annette Thau (Probus Publishing, 1992). It was written for the individual investor and covers all areas of the bond market, including governments, municipals, and corporates.
On a more professional level is Frank J. Fabozzi, editor, The Handbook of Fixed Income Securities (4th edition, 1994, Irwin). This is loaded with more information than most people want or need to know. However, it is a great resource.
So what are tax-free bonds? Those sound good!
Tax-free municipal bonds (often called munis) are debt securities issued by various cities throughout the United States. As such, they are given special tax-free status. If you live in, say, Indiana, and buy an Indianapolis muni, you will pay no federal, state, and, in many cases, local taxes on the interest you receive. But before you start dreaming of an IRS-free life, let's take a closer look. First, tax-free bonds usually come with a lower interest rate -- after all, you get to keep all of it, right? But how do you know that you won't come out ahead buying a higher interest rate bond and paying the taxes?
So how do I decide between a tax-free or a regular bond?
It's not that hard a decision. You simply convert the regular bond's interest rate to its equivalent "after-tax rate" and compare that with the tax-free bond's interest rate. Whichever is larger wins.
To find the after-tax rate, first you add up the your marginal income tax rates. If you are in the 15% bracket for federal income taxes and pay 4% in state taxes, your marginal tax rate is 19%. If you are in the 28% federal bracket and your state taxes are 7%, your marginal tax rate is 35%. Now you have to find the reciprocal of your marginal tax rate. Just subtract from 1. The reciprocal of 19% (0.19) would be 0.81, the reciprocal of 35% (0.35) would be 0.65. Now you can convert any interest rate to its after-tax equivalent.
Say you were considering buying a new issue corporate (taxable) bond with a coupon rate of 8%. The after-tax equivalent for someone in the 19% bracket is 6.48% (8% x 0.81), but for someone in the 35% tax bracket, the after-tax equivalent rate is 5.2% (8% x 0.65).
So for someone in the lower tax bracket, the tax-free bond would have to beat 6.48% to be a good deal, but for someone in the higher bracket, the tax-free bond would only have to beat 5.2%.
It works in reverse, too. To see how a tax-free bond compares to a taxable bond, divide the tax-free interest rate by your tax rate. A tax-free bond paying 5% would be equivalent to a taxable interest rate of 7.69% for someone with a marginal tax rate of 35% (5/.65= 7.69), but only equivalent to 6.17% for someone with a marginal rate of 19% (5/.81=6.17).
In general, tax-free bonds are usually only attractive to persons in the upper income brackets.
What percentage of bonds should I have in my portfolio?
Hold on there. You are assuming you should have bonds in your portfolio? There is a whole industry out there dedicated to convincing you of that, and people who make a living issuing pronouncements such as "Due to market machinations attributable to phase inducted waves in the upper troposphere we are instructing our clients to move from a 35% position in bonds to a 40% position until the deep geothermal wave pattern returns to an asynchronous mode." Right.
The whole portfolio allocation rap is just another facet of market timing. One can construct wonderful scenarios showing how much money one would have made by switching from stocks to bonds at strategic points in the past, but we have yet to find someone who can accurately and consistently call the shots for the future. Until we locate such a prognosticator, we suggest staying fully invested in stocks with all money that you won't need for the next 5 years. Gonna buy a house in three years? Put the down payment in some nice bonds, CDs, or even a money market account. But planning for retirement in 20 years? History has spoken pretty firmly on that one -- stocks have always done better over the long run.
Here at the Motley Fool we don't spend a lot of time on bonds because we are focused on your long-term investments and we don't think bonds are good for that -- but, hey, we also don't tell you what to do with your money, so if if it makes you feel better to have a few bonds in your long-term portfolio, be our guest. Just don't expect a lot from them. :)
For more on this topic see our Tax Q&A area.

subset: commoncrawl


text:
The Senate on Wednesday overwhelmingly passed bipartisan legislation aimed at addressing the Department of Veterans Affairs' scheduling crisis. The vote sends the measure to the House, where lawmakers have already approved some of the same provisions in separate standalone bills.
The bill, sponsored by Sens. Bernie Sanders (I-Vt.) and John McCain (R-Ariz.), would allow the VA to contract more with private medical centers to meet demand for care, in addition to granting the department authority to shift $500 million from its budget toward hiring additional medical staff and giving the VA secretary greater power to fire or demote senior executives for poor performance.
The measure, which passed by a vote of 93 to 2, would also expand certain benefits for former and current troops, providing in-state tuition rates for all veterans at public colleges and universities and increasing access to care for military sexual-assault survivors.
The vote came one day after the House passed a standalone bill that would allow the VA to contract more with private health providers. The House has also approved its own VA firing measure, but it differs slightly from the Senate version, which includes language ensuring that officials can appeal the personnel actions and receive a decision within one month.
The nonpartisan Congressional Budget Office on Wednesday released a report on the estimated costs for the Senate bill, saying the contracting provision could increase direct spending by about $35 billion over the next 10 years.
The CBO also said that enrollment numbers could rise under the bill because of improved access to care, costing the federal government an additional $50 billion per year to meet the growing demand.
Sanders, who heads the Senate Veterans Affairs Committee, said in an interview on Wednesday that the costs of the bill are justified.
"One of the costs of war is taking care of the men and women who fought in those wars," he said. "We have a moral obligation to do everything we can to make them whole, to provide the benefits and medical care to which they're entitled. If anyone disagrees with taking care of veterans, they shouldn't send them off to war in the first place."
McCain said on the Senate floor Wednesday that more measures may be necessary to address the VA's scheduling issues. "There will be more efforts to fix this gaping wound in America's conscience," he said.
Monday's vote moves the Senate bill to the House, where House Veterans Affairs Committee Chairman Jeff Miller (R-Fla.) and Ranking Member Mike Michaud (D-Maine) will take first crack at developing a final piece of legislation.
"I am absolutely confident that, working with Chairman Miller and Ranking Member Michaud, we can bridge the differences and send the president a bill he can sign in the very near future," Sanders said on the Senate floor.
Miller indicated during an interview on Tuesday that he would not try to derail the Senate measure. He said he does not agree with all parts of the bill, but he added: "It would be foolish for us to have 90 percent on the table and vote against it. If it takes a compromise with Senator Sanders, then that's what it takes."
Follow Josh Hicks on Twitter, Facebook or Google+. Connect by e-mail at josh.hicks(at)washpost.com. Visit The Federal Eye and The Fed Page for more federal news. Submit news tips and suggestions to firstname.lastname@example.com.


text:
Patience Needed With Pet Skin Problems
Dermatology cases can be a lot like looking for the proverbial needle in a haystack. Canine and feline skin has the habit of reacting to many insults in a similar manner. A pet may have an allergy, irritant reaction, bacterial infection, yeast infection, one of many different types of external parasites, an autoimmune reaction — even some types of cancer can develop a similar set of symptoms. Itchiness, hair loss, red skin, small bumps in the skin, pimple-like lesions, and scaling are symptoms of a laundry list of conditions.
The first part of a dermatological work-up always involves a physical exam. Unless the answer is then obvious, which it rarely is unless a pet is infested with fleas, I warn the owner that getting to the bottom of the problem may not be easy. We have to methodically start eliminating causes one by one, starting with the most likely culprits and moving down the list from there.
The process can take some time and often involves multiple rechecks. During the initial appointment, I'll collect a thorough history and run a few simple and inexpensive tests, including:
- skin scrapings to look for mites that cause a few different types of mange
- skin cytology to check for abnormal skin cells and bacterial and yeast infections
- a fungal culture to rule out ringworm
The fungal culture can take up to three weeks to complete, so while we're waiting for those results, I'll treat for anything I have diagnosed (e.g., a skin infection) and oftentimes prescribe a medication to eliminate the possibility of external parasites that can be difficult to diagnose via a physical exam and the tests mentioned above.
From here, the diagnosis and treatment plan follow a personalized flow chart. It the pet's problems are resolved with our first line treatment, we've found our answer. If the fungal culture was positive for ringworm, then obviously we head in that direction. If the pet is no better and the fungal culture is negative, we move on to the next phase in the work-up, which may involve a dietary trial to rule out food allergies, testing or empiric treatment for environmental allergies, or perhaps skin biopsies. I'll choose a direction to head in based on what condition seems most likely based on the pet's history and clinical signs. If that doesn't pan out, then we backtrack and head down another path.
Complicating matters is the fact that many pets suffer from more than one dermatological condition at a time. Here's a common scenario: A dog comes in for itchy, red, oozy, stinky skin. On the initial work up, we determine he has a yeast infection and successfully treat it. The redness, ooze, and odor are gone, but he's still somewhat itchy. Continued testing reveals he is allergic to several different types of pollen and storage mites. His allergies are responsible for his continued itching and were the underlying reason he developed the infection in the first place.
To achieve ultimate success in derm cases, veterinarians often have to go looking for "the rest of the story," as Paul Harvey would have said (I'm dating myself, aren't I?). Dermatology is nothing if not an exercise in patience — for vets, owners, and pets.
Dr. Jennifer Coates
Image: Pavel Hlystov / via Shutterstock


text:
With your socialized health care, low crime rate, and ability to create Nathan Steele's.
Thursday, March 26, 2009
5 comments:
- xbrooklynx said...
Jesus fuck i hate fox news. I think the new thing for conservatives is to see who can be more ignorant.
- March 27, 2009 at 1:44 PM
- Billy said...
This is definitely one of the best Onion Video News posts I've seen.
- March 27, 2009 at 2:14 PM
- Gardner said...
i like jokes
- March 27, 2009 at 3:52 PM
- xjoe jacksonx said...
1 asshole
2 mutants and the cliche hot neo-con broad, does anyone watch this show, no probably not
Fox News Red Eye can lick my brown eye
- March 27, 2009 at 6:35 PM
- 1000dead said...
i hope the russians invade Alaska so bad... and kill sarah palin... or at least stab er...
- March 29, 2009 at 12:14 PM
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text: For prospective elementary teachers. Includes a study of problem-solving techniques in mathematics, the uses and role of mathematics in our society, and the structure of our familiar number systems. Additional topics are chosen from number theory, ancient numeration systems, computer sciences, modern geometry and algebra and elementary logic. Prereq., one year of high school algebra and one year of plane geometry. The combination MATH 1110 and 1120 is approved for arts and sciences core curriculum: quantitative reasoning and mathematical skills.


text:
How do energy drinks give you energy_ – sfgate
(Inside Science TV) — Energy drinks are a $50 billion global industry, overflowing with different brands and exotic ingredients. But how do energy drinks actually give you energy?
The answer is familiar: caffeine and sugar. Caffeine makes you feel more energized by affecting your brain, while sugar refuels your body's cells and helps keep you physically active longer. As for any other ingredients, well… we'll get to them later. First, how do caffeine
and sugar actually work?
When caffeine reaches your brain, it crosses the blood-brain barrier and stimulates your brain cells – neurons – indirectly. It stops them from detecting the sleep-inducing chemical adenosine. This chemical builds up in your brain throughout the day and slows down the activity of your nerve cells. Block the effects of adenosine with caffeine and you feel less sleepy. Your neurons are more active and you feel more energized. But it's only made you feel more energized; it hasn't actually given you any new energy to burn.
That's where sugar comes in. You absorb sugar through your intestines into your blood where it can travel to all the cells of your body. Simple sugars, like glucose, are the fuel for all cells. The cells absorb sugar, and feed it into their powerhouses, known as mitochondria. The mitochondria create a merry-go-round of chemical reactions. This chemical cascade produces all-purpose energy chemicals that can then be spread throughout the rest of the cell and used like an energy currency. Absorbing sugar doesn't actually make you feel any more energized – and no evidence has been found for 'sugar highs' – but sugar does provide cells, like in your muscles and brain, with energy to keep them going.
Which brings us to all the other ingredients in energy drinks. There is no good evidence that any of these have any effect at all on either your mental or physical energy levels. That includes overhyped ingredients like Taurine, which your body makes loads of anyway – and is one of your body's fundamental building blocks necessary for normal heart, brain and muscle function; glucuronolactone, which is immediately broken down and then peed away in your urine, and the various B vitamins which are also peed out as waste, because you probably get enough of them already in your normal diet.
Like many things, energy drinks give you energy through good old-fashioned caffeine and sugar. The only difference is the flavor. Cheers!
Ali Jennings has a PhD in Neuroscience from University College London. He makes short, idiosyncratic films about science (some award winning!) and runs his own YouTube channel: AliHeartScience
Reprinted with permission from Inside Science, an editorially independent news product of the American Institute of Physics, a nonprofit organization dedicated to advancing, promoting and serving the physical sciences.
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Knit Magic offers, creative wellness through a combination of life coaching, knitting therapy and traditional classes.
In addition to our conventional private and group classes, we offer ground-breaking programs in the areas of personal growth, illness recovery, charity outreach, and smoking cessation. We also run The Brainwaves School of Creative Arts, a division that offers after-four programs in schools across the GTA.
Our mission is to enrich lives, enhance creativity, reduce stress, and improve overall health through knitting, and we believe absolutely everyone can benefit from it.
We are also passionate about making sure that knitting – which is an addictive pastime due to the favourable changes it creates in our brain chemistry – is done with a proper technique that will never lead to repetitive strain injury. Repetitive strain is rampant in the knitting community, and sometimes the negative effects of an improper technique don't appear for several years. At Knit Magic, we offer one-on-one assessments for knitters who want to make sure that they are using a proper, non-damaging technique. We also offer help for those who want to correct an improper or pain inducing technique.
Knit Magic was founded in 2006 by Karen Zila Hayes, a life coach, creative empowerment specialist and multi-media artist. Karen started knitting almost by accident, never dreaming that she'd someday be one of Canada's experts on knitting therapy, but the story of how it all came to be is a great one. CLICK HERE for more on the amazing 'accident' that started it all.


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drywall screw bit ?
are these any good ? i would rather not buy a whole drill.
I'm confused. That is used IN a drill. ....and it's totally un-necessary.
I drywalled my whole house with a phillips bit in my variable speed drill.
I have one of those somewhere. I ended up buying a Hitachi drywall screw gun ( reconditioned) for less than 40$ shipped. looks like new, works like new. 40foot cord. no learning curve, dont have to pay attention to depth once set up. if doing a large area, I'd get a drywall gun. then again, I've never been shy about acquiring a new tool :)
I bought one of those but ended up not using it.
For my entire house, I used a DeWalt 12V impact driver.
I've found that it gives me gives me much finer control than a drill driver
for putting the screw head just barely below the surface.
That said, I've never used a dedicated drywall gun; I suppose that it would be much faster,
especially since it has the screws right with the gun on a strip.
However, for me, I don't think that I could have done a 'better' job if had I used a
drywall gun.
at the time, it was on sale for 34 with 6.80 shipping when I got it.
This is what we've used in finishing a basement. Works great.
With Phillips screw bit, tendency to sink too deeply and rip the drywall.
I have had one for awhile but just recently had a need to use it... Wasn't impressed. Usually kicked the screw loose a bit proud of the drywall and I had to go back and set the screws. Ended up finishing the job with the impact. The ones I have are the same as the ones in the posted home depot link. I think the problem was that I was working an old house and the studs weren't a consistant density. If I hit a hard spot when the cup was just starting to push the bit out, it would cam on me. Some places it worked great, others, not at all. If you have a lot to do, I would say the Hitachi would be $50 well spent.:)
I use them from time to time. They work fine when I don't have my drywall gun with me and I'm doing a small job. The depth adjust works well. Its no replacement for an actual drywall gun but it's a heck of a lot better than trying to set a screw to the proper depth without one.
A drywall gun does more than just set the screw to the proper depth - which is really important as to not tear the paper and give proper hold.
It also pushes the drywall against the stud as you screw making for way less pop outs later.
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text: Ruffle-Front Shirtdress Style: 570043963 Out of Stock Love it? Everyone else did too. This item sold out! Use our search tool, chat online or call 1.877.948.2525 to find something equally desirable. Crisp, neutral-toned dress with a light luster and feminine details: cap sleeves, cascading ruffles, four pockets, and an A-line skirt with haberdashery stitching. 97% Cotton, 3% Spandex. Machine wash, cold. Imported. Hourglass fit. Topstitching embellishes the pockets, waistline and hem. Fully lined. Length: 40.5". Read More… Share on Facebook Tweet Pin


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Milligan students spend less and borrow less than most college students. And our educational outcomes are well-above our peers, providing you the best education and student experience. We're recognized as one of the best colleges and best values in the South by U.S. News & World Report and Washington Monthly. At Milligan, you get affordable quality.
- Milligan's total cost is $7,400 below the national average for private colleges
- Milligan's room and board is less than any other regional school and $5,000 below the national average
- Milligan's average net cost after scholarships and aid is $17,000
- Milligan graduates have less loan debt than most schools — $3,000 below the national average
Milligan is committed to keeping college affordable for our students. We'll work with you individually every step of the way. Check out our generous scholarships aid below.


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We feed souls!
On February 2, 2017 the Dude celebrated his 11th birthday.
(Design a Dude for our website!)
Click here to view some cheers for A Spacious Place.
Messages from our Founder/Executive Director
The "why" of A Spacious Place.
Everybody matters...everybody.
Everyone is creative. It's in our DNA.
A Spacious Place is a member of the Texas Association of Nonprofit Organizations.
The Key2Violence Project: click here for more information on how the project began.
Tailgate Offerings: A Spacious Place enjoys loading the trunks of our vehicles with creative goodies and motoring out to group homes, apartment complexes, camp sites, churches, and campuses. We currently provide service to the Mary Lee Foundation and Bona Terra, among others. If you know of an organization that might benefit from A Spacious Place's Tailgate Offerings, we'd love to hear from you! Contact firstname.lastname@example.com.
Join us as we unearth treasures from bygone empires—discover treasures in yourself as well!
Camp dates: July 31st — August 4th.More about camp.
We move kids from imagination into creation!
Click here to view the Top Ten reasons to join the Young Artists Club.
Who? Students in 1st Grade or older with BIG imaginations
What? A club that helps students turn their imaginations into visual art forms. After exploring the life and work of the "Artist of the Month," club members will create original pieces based on his/her subjects and style.
Where? A Spacious Place: 7105 Gentle Oak Dr. Austin, TX 78749
When? 2nd Saturday of each Month 1-4 pm
Come dressed to make art!
Why? Because it's fun to play with art materials!
Click here to enroll online or by phone (512-807-6863). Yearly dues are $65 for all students. Registration papers (emailed or posted to you after you register your student) are due the first day a student attends.
Next meeting: May 13, 2017 at 1:00 pm
Artist of the month hint: East Austin twins who team hip hop with abstraction.
Our Executive Director has written, and members of our Board have signed, letters to our government officials, asking them to vote against two current bills. We do this in accord with our Spacious values and with respect for the persons we serve. While ASP is not a political organization, we believe this is a way to give our prayers feet. Read the letter.
An A Spacious Place party ignites imaginations: under the guidance of our Spacious Crew, guests create their own fun. Whether it's a child's birthday party, a pool get-together, or an after-school event, our trained and background-checked artisans bring their best. And we bring the party to you! Click here for more information.
Scholarships are available. Contact David McKee at firstname.lastname@example.com or call 512.807.6863.
Check out our upcoming Offerings: Click on the Offerings tab above to view upcoming A Spacious Place offerings, including creativity courses, arts events, concerts, and showings. The Offerings tab also has information on previous courses.
A Spacious Place Blog: It's here. Click on the Blog tab above to see our blog. Sign up and join our community conversation. We look forward to hearing from you!
Graffiti Wall: A Spacious Place provides space for your creative expression. If you have a brief meditation, a poem, or any random thoughts, click here to submit them. We will post your creative work for others to read. No profanity please.
Our "Playground Principles" represent a compilation of wisdom from the fields of education, pastoral care, spiritual direction, and even global economics. We use these principles in all of our offerings.
A Spacious Place was born on Groundhog Day, 2007. Since then we have hosted 12 creativity camps, some onsite and others at SafePlace and SafePlace affiliates. Camp themes included Celebrate Creativity, Kids Rock!, Super Heroes, Myth & Magic, Technical Difficulties, Mystery, Slice-O-Life Multi-cultural Arts, and Crazy Dreams. We provide ongoing creativity classes to Mary Lee Foundation's Daybreak and to Bona Terra, and a monthly Young Artists Club and a Young Writers Club. Our Young Writers Club wrote and published a book. Our Young Artists Club had a gallery show. We also host Ramah Faith, a website for creative expressions of grief and loss, as well as an online prayer wall.
We've hosted classes on C. S. Lewis' Chronicles of Narnia, on photography, on arts expressions for life's agonies & ecstasies, on the Beatitudes, on creative writing, on the Dark Night of the Soul, and on CPR & First Aid. We've provided one-day creativity centers for AISD Project Help's Empowerment Academy, VSA's Art in the Park, Spirit Rein's Day Camp, and Help Portrait. We produced a children's production of The Best Christmas Pageant Ever and hope to stage more plays in the future.
Each November we host Gifted2Give: a service event in which participants create holiday gifts at low or no cost from simple or recycled materials. We began "The Key to Violence Project," which encourages persons to transform violence through love and creativity.
A Spacious Place's seminal event was a doctoral project offered by Kaye McKee in which participants explored God metaphors through their own creative expression. Click here for more information.


text: Vintage Charm Ruana Style: 570088564 Out of Stock Love it? Everyone else did too. This item sold out! Use our search tool, chat online or call 1.888.855.4986 to find something equally desirable. Comfort is the ultimate luxury; our knit ruana is the ultimate layer. Ruana silhouette with open sides. Length: 29". 67% cotton, 15% rayon, 12% nylon, 3% wool. Hand wash, cold. Imported. Read More… Share on Facebook Tweet Pin


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Police Blotter: RPD attempting to ID possible trailer thief
Police are attempting to identify the driver of a truck possibly involved in trailer theft. (Courtesy Photo)
Detectives from the Roswell Police Department are attempting to identify the driver of a truck possibly involved in a utility trailer theft. The incident occurred sometime between April 21 and April 23, on the 900 block of West Hobbs Street. The stolen utility trailer [auth] is described as an early 1990's S&H box utility trailer. It is dark gray in color and the top is rusted.
If anyone has information pertaining to this case please contact the RPD 624-6770 or Crime Stoppers 1-888-594-8477.
Vehicle reported stolen
Roswell Police responded to a report of a stolen vehicle on the 800 block of West Mathews Street on Thursday. A Honda Accord was stolen while parked in a driveway. The estimated value of the vehicle is $18,000.
Beer tap taken from vehicle
A report of larceny from a motor vehicle occurred on the 1600 block of South Michigan Ave. on Thursday, according to Roswell Police reports. No sign of forced entry was found. Over $200 in items was stolen including a beer tap, and jewelry.
Two overdose on pills, alcohol
Roswell Police responded to a report of an overdose on Thursday where two young adults had consumed several unknown pills and alcoholic beverages. One of the young adults was unresponsive but breathing. Both sought treatment at a local hospital, according to police.
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Cleveland State tuition is rising
(Cleveland) - The cost of attending CSU is rising, but students who move toward graduation at a quick and steady pace can save money.
Even though Cleveland State is raising undergraduate tuition by 2%, university trustees have created a program that provides students with a rebate if they complete 30 credits in an academic year.
Students can receive a $100 textbook credit each semester if they are in good academic standing. Its part of an effort to shorten the time it takes students to graduate.
Get breaking news sent to your mobile phone. Text "news" to 21095.
(Copyright 2013 Clear Channel, all rights reserved.)


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In this section, we are going to calculate the sum of two 2 X 2 matrices containing rows and columns. For this , we need to declare two dimensional array of integer type. Here, we prompt the user to input values for two matrices. To make the matrix of 2 X 2, we are using for loop. By the use of for loop, the values will get arrange in rows and columns. After getting both the matrix, the matrices will be added by using the for loop with a[i][j]+b[i][j].
Here is the code:
#include <stdio.h>
void main() {
Enter the First matrix: 1 2 3 4 The First matrix is: 1 2 3 4 Enter the Second matrix: 5 6 7 8 The Second matrix is: 5 6 7 8 The Addition of two matrix is: 6 8 10 12
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The Community Building and Social Change Group at Johns Hopkins
Community Development in East Baltimore: The Community Building and Social Change group at Johns Hopkins
It's January 21, 2012, and it is STILL winter break! I love Hopkins. Not only because we have almost 7 weeks to relax before the spring semester, but also because we're given access to just about everything we need to make a difference in the lives of Baltimore residents. I have had the awesome opportunity to direct the Community Building and Social Change group, a 503 (c) non-profit organization registered with the Center for Social Concern that works closely with residents of Baltimore city. CBSC aims to understand residents' needs and then come up with an actionable plan to help resolve the problem. We go out into the community and poll residents on some of their greatest challenges. We compile the results and then ask residents what they would like to see as a response to those issues. We then sort through issues and solutions and receive student input to come up with a solid proposal. CBSC aims to be completely bottom-up—top down approaches to development are often paternalistic and ignore the ability of people to participate in their own transformation. So you can see that the process here is kind of complicated—you want to help others, but you want to do so with respect for their dignity and agency.
The CBSC approach is rather innovative. First, we have no "member base." Instead, thereare a few leaders who manage and organize all projects and logistics. You can imagine that this is a huge task, but rightly so—the most dedicated leaders will be responsible for most of the behind-the-scenes work. CBSC thinks this is the right approach, since managing a member base is difficult at any school in and any line of work; weekly meetings, listservs and emails sometimes tend to put off people who would normally be interested in development. Instead, when carrying out projects, CBSC enlists the help of pre-existing student groups: community service organizations like APO and Campus Kitchen, health groups like Health Leads, Hopkins organizations like the student government (and the student activities center), religious groups on campus like the Jewish Students Association and the Muslim Students Association, and fraternities and sororities on campus. By mobilizing members of other groups, CBSC avoids the problem of under-commitment.
Second, CBSC gives all group members voting power in that they can help determine the implementation of projects and the creation of new community ventures. While this poses the potential problem of information overload—that we have too much feedback and not enough time to sort through everything—we think it is better to have too much advice than not enough.
CBSC has accomplished quite a lot over the last five years. But there is still much more to do. While I would love to talk more about Hunger for Help and our other projects, I want to keep this entry more general so that you can get a better idea of the organization and decision-making involved in community development here in Baltimore. I definitely encourage you to visit our webpage at www.hopkinscbsc.org, or email me at firstname.lastname@example.com for more information. Until then, enjoy the rest of your winter break! Or, umm,enjoy the rest of your school year ;)


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America needs a bullet train
Tell the Governor Rick Scott, do not block progress, America's high-speed train, to help our people to overcome the dependence on foreign oil, clear roads of high traffic hours, the job creation and overall progress .
Our country and the world face the most complicated problems that humanity had imagined, but especially here in America the change we need, even when our most chauvinistic ideas are not permitted to do so, the force of history and the people will fall over us.
Many things we have left to do for America, let's return the dignity and patriotism ... Say yes to the Bullet Train and the Progress.
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