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All you would be able to steal is the soundtrack then.


From Wikipedia: https://en.wikipedia.org/wiki/High-bandwidth_Digital_Content...

> it must not transmit high definition protected video to non-HDCP receivers; and DVD-Audio material can be played only at CD-audio quality[7] by non-HDCP digital audio outputs (analog audio outputs have no quality limits)

Analog hole is still analog hole, and the MAFIAA wants to close it.


If you can play CD quality audio, it's hardly a hole. Better quality is only useful during creation/mixing. It's not like DVD audio is better, even if it has a higher sampling rate (probably worse then actually) or higher bit encoding.


There are other problems why the analog hole is hard to exploit:

1) Multi-channel streams are easy to grab in digital, but expensive to grab in analog - simple reason: six channels that have to be captured in exactly the same time, without offset. Most consumer-grade sound cards only carry one line-in, not three of them.

2) Power supplies in computing tend to be NOISY. I mean, REALLY noisy. So basically the PSU adds noise to the output DAC, and then the PSU adds noise at the ADC stage. It most definitely is a quality loss.

3) Naturally, headphone-outs and in a lot of cases line-outs tend to be engineered in a way that their output impedance can drive headphones, too. This can massively distort the signal.

4) Clipping. Hard enough to avoid when using a professional mixing table, next to impossible to avoid when ripping audio via the analog hole.


Humans can hear up to 28khz when paying close attention. "CD Quality" is slightly below the threshold of hearing, at a point where most people don't notice the difference or care to notice the difference.

It's also somewhat poorly-defined, because "CD quality" can mean lousy mid-range performance when rounding 24-bit to 16-bit, or high frequency hiss when noise-shaping 24-bit to 16-bit.

So "CD quality audio" is quite a degradation when you listen in a 100% quiet room with expensive speakers and your full attention.


28kHz is either a typo or you give too much credit to human ears. 18kHz is more likely the real figure.


That depends on the ears, that's why the ultrasonic youth drive-aways are so successful. Old people simply can't hear them due to age and external degradation (loud rock music concerts).

I, for example, can hear these ultrasonic weasel defenders, which operate between 20 and 30 kHz, again - when I used to work on outside construction works using massive jackhammers, excavators etc. I couldn't because daily stress would fuck up my ears.


I have my doubts that humans can hear above 20kHz.

It's more likely that the sound produced by those devices, even if ultrasonic, may produce intermodulations in the audible range.


28 kHz is in fact correct, although only in lab conditions:

> The commonly stated range of human hearing is 20 Hz to 20 kHz. Under ideal laboratory conditions, humans can hear sound as low as 12 Hz and as high as 28 kHz, though the threshold increases sharply at 15 kHz in adults, corresponding to the last auditory channel of the cochlea.

(ref: https://en.wikipedia.org/wiki/Hearing_range)


Even 18kHz is too high. Adolescents can only sometimes hear as high as 17kHz, and adults can often only hear as high as 14kHz.




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