Same for me. The beam didn't have to bounce off anything other than my head. Thewall or object bounce does work, but it isn't always needed.
I've also heard Tom Danely's HF spotlight thingy. A massive array of compression drivers. It's very hard to hear off axis, but will reflect off a wall amazingly well.
You can hear quality reproduction, even if ones HF hearing response is not what it used to be in ones 20's.
I am much more aware of imaging, stereo width, bass performance etc than when I was younger. Interestingly, even though my kids have much better frequency response than me, I always feel they prefer a response that is more bassy and more trebley than I do. What is that all about? It should be me that's cranking up the treble! And yet, when I put a well recorded track on, with lots of space and 'air' invariably their response is 'wow'.
I am much more aware of imaging, stereo width, bass performance etc than when I was younger. Interestingly, even though my kids have much better frequency response than me, I always feel they prefer a response that is more bassy and more trebley than I do. What is that all about? It should be me that's cranking up the treble! And yet, when I put a well recorded track on, with lots of space and 'air' invariably their response is 'wow'.
The question that I have had is that the audio band signal does not exist until the beam hits an object (including your ear). Since the audio propagates in all angles after the reflection, even on a hard smooth surface my thoughts were that the IM that generates the audio happens at the surface and not in the air before the beam hits the surface.
The DSP necessary to make the audio work must be pretty impressive.
I meant 103. My finger missed the 10 key and hit the 9 key..... [or maybe I just didnt see the 10 key.]
Does this mean I have to sell my ZR1?
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It seems plausible for the ultrasonic heterodyne stuff that reflecting from a surface would significantly augment the downconverted energy, just as an audible-frequency transducer's output is much more audible when in an enclosed, or partially-enclosed, space. I don't think the "demodulation" requires the reflecting surface, but once the sonic energy is there it interacts with the surface and there is some "gain".
When I worked on powered speakers at Harman, one guy used to look at frequency response plots from the anechoic chamber, and if there was noticeable excess at low and high frequencies, would describe it as looking "smiley". This was something to be corrected.
He is a link to one of the hearing protection pages with min. standards.
http://www.europages.com/filestore/gallery/5/41/9151731_b6bf2771.pdf
http://www.europages.com/filestore/gallery/5/41/9151731_b6bf2771.pdf
As a youngster I built an AM "headphone" to see if I could "hear" by internal detection. Might have used 455KHz for the carrier, but I don't even remember the results (enough to believe). Probably only around to tell about it because the antenna must have been really poor.
This was the Beach Boys/ girl groups era, and I must have heard about it from somewhere. ?
Thanks,
Chris
This was the Beach Boys/ girl groups era, and I must have heard about it from somewhere. ?
Thanks,
Chris
There was an inventor, one G. Patrick Flanagan, who developed what he called iirc the "Neurophone". It was also just an AM transmitter with pads for your ears. With a bit of help from my father I built a version in my first year of high school, and it did work, although the underlying mechanism was unclear. "And I alone am escaped to tell thee".
I think Flanagan went off the deep end a bit at some point, because I remember a book of his I have lost long ago. I think it was called Pyramid Power, and I recall the picture of the author standing proudly in front of a tent with a $hit-eating grin on his face.
All of this without looking on the web! Makes me feel younger, for a moment at least. Now someone will see how many errors I made.
In fact I referred to someone who wished to get Toole's job, and told him so when he was interviewed. His plans have not run as he desired, although he is still gainfully employed in Northridge as far as I know.
Floyd was hired to put objective and systematic measurements in place, and to extend the work he'd done at NRC, replacing what used to be the typical cycle of earnest engineering development followed by pretentious golden-ear and marketing types auditioning the prototype and shouting More highs! More bass! and storming from the room. Things reached the nadir when Jacoby milked what was left of brand recognition and really trashed things. Fortunately TJ was found out in some juicy flagrante delicto events, and had to leave.
And I'll say it again: you can't make this stuff up.
HK has been a strange place to work at, over the decades. They started with pretty good, but not perfect tube technology, then one of the first 'successful' germanium based preamps, the Citation A, I think it was, then they went to silicon quasi-comp power amps with indifferent component selection, and a strong belief in WIDE BANDWIDTH. Even I questioned their WIDE BANDWIDTH theory when I worked there in 1977-8, because it was so extreme. They had 'golden ears' on staff, who would evaluate everything made, and they had pretty good ears. Unfortunately, they also had the majority of managers as middle management drones, who could work at an aircraft company with equal ease, or something else. Audio was just the commodity that they made.
When Floyd Toole and his successors got on board, everything changed to double blind testing, etc. Electronics quality was then undervalued, and speaker frequency response, overvalued. I have nothing from HK in my audio system, but they made through JBL, a pretty good horn midrange, and a direct radiator woofer system that they showed at CES a few years ago.
When Floyd Toole and his successors got on board, everything changed to double blind testing, etc. Electronics quality was then undervalued, and speaker frequency response, overvalued. I have nothing from HK in my audio system, but they made through JBL, a pretty good horn midrange, and a direct radiator woofer system that they showed at CES a few years ago.
That's it! Maybe it really did work. Scary thought.
Wikipedia says he's married to Crystal Gale (well, not really).
Much thanks,
Chris
There is confusion here and I can't find the patents right now, the beamforming with phased arrays of compression drivers is not the same. There is only ultrasound and yes the audio is created in "thin air". Seeing the highly directional nature of the audio requires solving some difficult equations, the low frequencies are generated along the beam and do not radiate sideways (much). This is why the lows are difficult to do (you need wavelenghts along the beam).
The sound is not simply created everywhere in the beam, it is forced into the longitudinal direction. thinking of it as "pixels of air" being made to throb in all three directions is wrong.
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