I do believe they claim that they use inaudible sounds, i.e. something outside a human's hearing range. Sorry, but chances are your TV is going wonky on you.
I remember growing up always hearing around the house the hum of the CRT TV when my parents would turn the cablebox off and not realize they left the tv running. Parents never heard anything. You start to lose hearing at upper frequencies around as early as in your 30's... when I talk to my friends about this, a surprising number of them (even the non-techies) remember this barely-audible-CRT-hum noise pollution phenomenon.
The upper range of human hearing is about 20khz. From a design and manufacturing-costs point of view, it doesn't make sense to design a speaker that can reproduce sounds much above human hearing. If you're gonna be optimizing the speaker cone for anything, you're probably gonna set an upper bound around the upper range of human hearing, maaaybe go a little bit above if you're high quality and want to reproduce everything.
So, your average TV speaker is probably going to reproduce some sounds above the upper range of human hearing, but not too far above. The higher into the inaudible range you design your beacon, the more likely it's not going to work, because not enough TV's are going to be able to reproduce it and your system becomes unreliable.
If I was building such a beacon, there's a good argument to be made to target your signal tone at or slightly below the upper range of human hearing, making it audible.
So (unless I don't know some detail about speaker design and there's a class of speakers that aren't generally limited at around 20khz, in which case please share) I actually think it's likely they're using almost-inaudible tones. In which case OP should smile knowing 1) he's not yet losing his upper range of hearing, and 2) he's now experiencing the new generation of the barely-audible-CRT-hum noise pollution phenomenon.
-------
[edit: yep, looks like that's exactly what they're doing. Check out this short blog post from a comment further down about a guy spectograph-hunting for these:
The bottom of the post links to a patent for this tech. "It refers to the insertion of frequency-shift keying modulated data at 17.5 and 18.5 kHz." Boom. Right in the fuzzy area of the limits of human hearing. ]
> I do believe they claim that they use inaudible sounds...
The odds that a television manufacturer [0] has designed most of its TVs with speakers that can reliably reproduce either ultrasonic or subsonic frequencies are near-zero.
The odds that the marketing arm of a niche tech company will be dreadfully (some might say fraudulently) imprecise with their marketing copy are really, really high.
...unless they're starting to design TV's exactly for these "enhanced viewing experiences" and opening up a side-channel of profits to marketers and folks like Nielson.
Wasn't there one of the asian manufacturers the other month (I wanna say... Samsung maybe? please correct me if I'm wrong) that got caught building a SmartTV that recorded audio and sent those packets up through the network to who-knows-where? They eventually rolled that feature back, but not before they got enough press that they had to make a statement saying it was only for diagnostics or testing or something like that.
If you're, say, a multinational with a large mobile device division and a strong corporate mandate to make sure the mobile device ecosystem stays strong so profits keep flowing, is it too far fetched to think you would start looking for cross-division synergies that, lets say, grease the flow in this ecosystem? Perhaps you could introduce an extra component (or optimize an existing one for different parameters) that if, say, it saw a signal of a certain form, it might reproduce it in an invisible and obtrusive way. And if it helps major players in the device ecosystem, well, great, the ecosystem stays strong and mobile devices continue to roll off the shelf.
Complete speculation, but not an unreasonable line of thinking?
> ...unless they're starting to design TV's exactly for these "enhanced viewing experiences" and opening up a side-channel of profits to marketers and folks like Nielson.
This presumes two things:
1) Enough TVs are made with speakers that can reliably reproduce actually ultrasonic or subsonic vibrations.
2) Enough microphone ship on devices that can reliably detect actual ultrasonic or subsonic vibrations.
I don't see this happening any time soon.
Hell, it'll be easier [0] to get this sort of information from the cable company by way of the cable box attached to the TV, or easier and (probably) cheaper to get this info from video playing software [1] that runs on the TV, or the inbuilt CATV/OTA tuner. [2] Maybe mix in an approximate headcount from the camera embedded in the TV to "enrich" the data.
Cameras embedded in TVs? Apart from the Samsung "smart TVs" with an obvious camera that can be rolled in/out of use, are there really cameras on television sets? I've heard people talk about hidden cameras in set top boxes and tvs for at least a decade, but it always sounded like nonsense. It has the potential to go really bad if people discovered something like a camera hidden.
> Cameras embedded in TVs? ... I've heard people talk about hidden cameras in set top boxes and tvs for at least a decade, but it always sounded like nonsense.
I never asserted that the cameras would be hidden. :)
Like you said, cameras are embedded in at least one model of "modern" television. Either laziness or "gamification" can be used to get many folks to keep the camera in the in-use position.
However, TV sound is band-limited (Analog TV at ~ 15kHz IIRC, the higher band is used for CC), not sure about digital tv, maybe 20kHz (not considering limitations on the sound circuits + speakers)
NTSC had an upper frequency limit of about 16kHz but AFAIK Nielsen boxes still picked up what was playing from "inaudible" signals. Whether that's a high frequency tone or a broadband watermark I don't know.
I remember growing up always hearing around the house the hum of the CRT TV when my parents would turn the cablebox off and not realize they left the tv running. Parents never heard anything. You start to lose hearing at upper frequencies around as early as in your 30's... when I talk to my friends about this, a surprising number of them (even the non-techies) remember this barely-audible-CRT-hum noise pollution phenomenon.
The upper range of human hearing is about 20khz. From a design and manufacturing-costs point of view, it doesn't make sense to design a speaker that can reproduce sounds much above human hearing. If you're gonna be optimizing the speaker cone for anything, you're probably gonna set an upper bound around the upper range of human hearing, maaaybe go a little bit above if you're high quality and want to reproduce everything.
So, your average TV speaker is probably going to reproduce some sounds above the upper range of human hearing, but not too far above. The higher into the inaudible range you design your beacon, the more likely it's not going to work, because not enough TV's are going to be able to reproduce it and your system becomes unreliable.
If I was building such a beacon, there's a good argument to be made to target your signal tone at or slightly below the upper range of human hearing, making it audible.
So (unless I don't know some detail about speaker design and there's a class of speakers that aren't generally limited at around 20khz, in which case please share) I actually think it's likely they're using almost-inaudible tones. In which case OP should smile knowing 1) he's not yet losing his upper range of hearing, and 2) he's now experiencing the new generation of the barely-audible-CRT-hum noise pollution phenomenon.
-------
[edit: yep, looks like that's exactly what they're doing. Check out this short blog post from a comment further down about a guy spectograph-hunting for these:
http://altmode.org/2015/11/13/searching-for-ultrasonic-beaco...
The bottom of the post links to a patent for this tech. "It refers to the insertion of frequency-shift keying modulated data at 17.5 and 18.5 kHz." Boom. Right in the fuzzy area of the limits of human hearing. ]