Excellent article! Personally I always liked 8 track and cassettes in terms of their inherent musicality compared to off the shelf CDs. Regardless of issues regarding tape hiss, bandwidth limitations, and the like, which I think are overblown.

Now, I also think it's true that the data encoded on the CD does not manage to get to the listener's ears without some effort. The off the shelf CD is like an archaeological "dig" - excavation is necessary in order to obtain the information buried in the data. Unless these excavation steps are taken, CDs tend to sound rather generic, bland, threadbare, hollow, uninvolving, unpleasant and disappointing.

Cheers

NPR's 'all things considered' tends to get to the crux of the matter. It looks like a good assessment of the current situation and what is likely in the near future. Despite my (and audiophiles) preference for the best sound possible, th rest of the parameters, primarily the convenience, holds sway with the public.

One rant I would say is that many things today are presented as a ton of 'features'. You can do 'this' or 'that' and you can even do 'these' things with this product. But what's missing is what was not said, that you lose quality.

Cable TV crams a lot of signal through a small pipe (lossy compression?). They advertise the hundreds of channels available but do not say they compress the signal to do so. They may give you full HD at the end but the original program may not have been in HD, so it's not really HD.

Over-the-air transmission of TV does not have to compress the signal. Broadcaster may do so if they choose.

These are examples of things done, similar done to product ads. The article Stephen refers to basically says that the movers and shakers steer people away from quality without even hinting at that, so that the society is moved toward more profits for whomever pushes this idea.

Part Two: How Musicians Create discusses how digital music has altered the musicians' relationship with their art and their audience.

Fascinating stuff. My feeling is that music, and art, will become more and more beautiful and abundant as artists find better ways of meeting the (emotional, intellectual, practical) needs of their audience. This is why I think vinyl LPs (and now cassettes, too) are becoming more popular.

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Cable TV crams a lot of signal through a small pipe (lossy compression?). They advertise the hundreds of channels available but do not say they compress the signal to do so. They may give you full HD at the end but the original program may not have been in HD, so it's not really HD.

Although the best methods are not pure frequency-based upsampling like in audio, the conversion of SD to HD is another form of upsampling, and just like it audio, it can't add any more information.

And very often you can see the lossy compression artifacts.

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Over-the-air transmission of TV does not have to compress the signal. Broadcaster may do so if they choose.

Sorry, no, ALL ATSC HD signals are heavily compressed, you can't avoid it. The question is not "is it coded" (I prefer the word "coded" to "compressed" because the word "compressed" is overloaded 99 ways from Sunday...) but rather "what rate is it coded at". Some stations still put out only one primary signal, and have very good quality. We have one here that puts out 4 signals, 1 HD of 'ok' quality and 3 sd, the last of which is, well, low quality, but of unmoving (for the most part) data.

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These are examples of things done, similar done to product ads. The article Stephen refers to basically says that the movers and shakers steer people away from quality without even hinting at that, so that the society is moved toward more profits for whomever pushes this idea.

The present "wisdom" in business is MORE CHANNELS MORE CHANNELS LOUDER CHANNELS LOUDER LOUDER LOUDER.

This, of course, is one reason (there are others, I'm well aware of them, needless to say) that the business is going under.

The way artists are treated, the sham of distribution, the way they peeved off their customers by suing them, the way they closed down the best advertising agency they ever had and sued it, the "OUR MODEL OR NOTHING AT ALL" attitude...

The list is very, very long.

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Part Two: How Musicians Create discusses how digital music has altered the musicians' relationship with their art and their audience.

Fascinating stuff. My feeling is that music, and art, will become more and more beautiful and abundant as artists find better ways of meeting the (emotional, intellectual, practical) needs of their audience. This is why I think vinyl LPs (and now cassettes, too) are becoming more popular.

More to the point, such delivery method sgo around the usual CD marketing methods, and so they don't have to be (and can't be, thank you) ultracompressed, annoying, and so on.

It's possible to make an LP sound like a CD, but not vice versa, but nobody does it. Rather they want it LOUD LOUD LOUD. (If you detect a bit of annoyance there, well yeah, what they did to Emmylou Harris's last album ( at least the last one I bought) is obscene.)

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Although the best methods are not pure frequency-based upsampling like in audio, the conversion of SD to HD is another form of upsampling, and just like it audio, it can't add any more information.

And very often you can see the lossy compression artifacts.

That is true. It does not. However, when the eyes sees the frames as in motional video, detail that was in one frame and not in another, can and does appear. But only in motion and to the eye/brain system. Freeze frame the image and it goes back to being a simple upsampled SD individual frame. Motionally, the situation is entirely different.

Interestingly enough, the larger group of the video aficionados were so hard to reach on this Basic point that the bulk of them, at the AVSforum, took a good solid two years to mentally reach that understanding. This is not a very good indication of the overall human system of balance or internal checks and balances when it comes to overall human development, as it was and is such a small thing to attempt to 'get past'.

As above - so below. Etc.

Oddly enough, a similar tactic can be applied when attempting to understand audio sampling and associated issues.

IME, (In My Experience) Empirical observation rules over that of established theory when direct observation indicates otherwise, ie something at work that is not wholly inclusive with regard to being explainable via the static aspects of prior theory. This is a notable failing point of scientific pundacy, or scientific dogmatism, when it comes to attempting to understand the given quandary that may arise.

I'm not being argumentative -just showing potential avenues for exploration.

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Cable TV crams a lot of signal through a small pipe (lossy compression?). They advertise the hundreds of channels available but do not say they compress the signal to do so. They may give you full HD at the end but the original program may not have been in HD, so it's not really HD.

Although the best methods are not pure frequency-based upsampling like in audio, the conversion of SD to HD is another form of upsampling, and just like it audio, it can't add any more information.

And very often you can see the lossy compression artifacts.

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Over-the-air transmission of TV does not have to compress the signal. Broadcaster may do so if they choose.

Sorry, no, ALL ATSC HD signals are heavily compressed, you can't avoid it. The question is not "is it coded" (I prefer the word "coded" to "compressed" because the word "compressed" is overloaded 99 ways from Sunday...) but rather "what rate is it coded at". Some stations still put out only one primary signal, and have very good quality. We have one here that puts out 4 signals, 1 HD of 'ok' quality and 3 sd, the last of which is, well, low quality, but of unmoving (for the most part) data.

Let me take a shot at clarifying the above, for anyone who needs it.

TV stations receive HD signals from their networks that are losslessly encoded as, essentially, mpeg 2 streams.

They are decoded at the station end as full bandwidth ('full' translating for us non-technical folks as 'as good as it gets') and sent out from the broadcast towers compressed at about a 15:1 ratio, which yields 19 mbps.

At least, that's the idea. Think of 19 mbps as blu-ray quality, as 1080p quality.

In fact, most tv stations live in the 15-16 range, or 'less than perfect high def though it still looks good on most shows.'

The feed to cable is, in the case I am most familiar with, uncompressed. Cable transcodes the signal. It is also widely believed that cable compresses it hard, and especially the signals of local tv stations, though I don't know first hand what kind of compression is used.

s.

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TV stations receive HD signals from their networks that are losslessly encoded as, essentially, mpeg 2 streams.

Losslessly? Uh, no. Not the video.

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They are decoded at the station end as full bandwidth ('full' translating for us non-technical folks as 'as good as it gets') and sent out from the broadcast towers compressed at about a 15:1 ratio, which yields 19 mbps.

Sorry, but that depends entirely on what else the broadcaster is sending along with the main HD feed.

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At least, that's the idea. Think of 19 mbps as blu-ray quality, as 1080p quality.

1080p maximum possible quality is

10 bits (per color per pixel) * 3 (colors) * 1080*1920 Size of frame in pixels) *60 (framesecond, level 4.2 AVC) = 3,732,480,000 bits/second.

That's the simple math. 3.7 gb/s is reduced to 19 mb/s. That's what you call heavy compression. Fortunately, video can take it with good compression and AVC/H264/VC9. MPEG-1/2 video is not as good a compression format, MPEG-2 container or not.

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In fact, most tv stations live in the 15-16 range, or 'less than perfect high def though it still looks good on most shows.'

Sorry, no again. Some of ours around here have an additional 5mb/s feed for a good stv, some have two stv feeds that are somewhat degraded along with an "hd" feed in their on-air signal.

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The feed to cable is, in the case I am most familiar with, uncompressed. Cable transcodes the signal.

"Transcode" means "go from one coded (i.e. compressed) signal format to another. So if this is "uncompressed" they aren't using a transcoder, but in fact I dare say that any network feed will be compressed. You need to look into what's going on here quite a bit more. You seem to be saying that cable gets 3.7 gb/s per HD stream, (lossless will half that or a bit more, but not get it down under 1 gb/s), which would surprise a lot of people I know of.

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It is also widely believed that cable compresses it hard, and especially the signals of local tv stations, though I don't know first hand what kind of compression is used.

s.

Depends on the cable company. Most use an interleved transcoder that does many channels at once, and uses some TASI gain over a large channel set.

I understand your desire to show your knowlege but I would also suggest that you dig in a bit more before you continue here.

jj -

I'm sure you know vastly more about this stuff than I do, and I made a hash out of my original post by glossing over a few points, in the interest of simplicity.

First, as regards mpeg 2 and my use of the word 'lossless.' You're correct, strictly speaking. What I was trying to say is that the stream passed to the tv station is a full 1080 stream.

It comes, as I understand it, in an ASI (asychronous serial interface) wrapper. Internally, it gets passed around as ASI. (There is another option here for how it gets passed around, but I don't know what it is.)

My point about 19 mbps was not to suggest tv stations really do that - it was to say 'here's the standard.'

For instance, (as you suggest) a station may set its hd encoder at between 14 and 15 mbps, with the balance being used for an sd signal.

On the subject of what cable gets, I was trying to say "it doesn't get any additional compression from the broadcast end." It gets the same signal that goes to the tower.

And no, cable doesn't get 3.7 or 1.5 gigs, or anything like that.

I know absolutely none of this natively, as I assume you do. My *knowledge,* such as it is, comes from the engineers at the tv station where I work - our transmitter guys and the guy who set up and maintains the path through the facility.

s.

Thanks to satkinsn and jj. I was under the impression from various sources that cable compresses even more of the signal that comes to them from the broadcasters. You both cleared that up.

Unfortuantely those sources are past the tertiary generation of information chain and did not go to the original sources and 'ones who may know better'.

Edit:

I do not see any visible difference on program material between a channel that broadcasts one HD and two SD signals compared to one that broadcasts only one HD signal over-the-air. Maybe if they showed a test pattern it might be easier to see?

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Thanks to satkinsn and jj. I was under the impression from various sources that cable compresses even more of the signal that comes to them from the broadcasters. You both cleared that up.

Unfortuantely those sources are past the tertiary generation of information chain and did not go to the original sources and 'ones who may know better'.

I don't understand your last sentence. What are you saying?

To be clear, it's widely believed cable compresses the signal after it's brought in, but I have no firsthand knowledge of that.

jj knows more about this - his last post had some notes on what the cable co.s do.

More generally, I want to be clear (again) that I don't know much about this business firsthand; my information comes from some long conversations with our engineering staff, which still doesn't mean I know what I'm talking about.

My *only* point in posting was I thought I could make things a bit clearer - I don't think that was a good call on my part.

s.

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Thanks to satkinsn and jj. I was under the impression from various sources that cable compresses even more of the signal that comes to them from the broadcasters. You both cleared that up.

Unfortuantely those sources are past the tertiary generation of information chain and did not go to the original sources and 'ones who may know better'.

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I don't understand your last sentence. What are you saying?

To be clear, it's widely believed cable compresses the signal after it's brought in, but I have no firsthand knowledge of that.

jj knows more about this - his last post had some notes on what the cable co.s do.

More generally, I want to be clear (again) that I don't know much about this business firsthand; my information comes from some long conversations with our engineering staff, which still doesn't mean I know what I'm talking about.

My *only* point in posting was I thought I could make things a bit clearer - I don't think that was a good call on my part.

s.

Sorry for the confusion; that's the result of me trying to write a post when I was in a hurry to get out the door.

What I meant is that the sources I looked at seem to say that cable providers have to compress the signal whereas the over-the-air broadcasts do not, with respect to the lossy vs. lossless types. Those sources I heard from are not from people like jj who seems to have direct knowledge of this, or you who have access to the station engineers. The info I got may be farther removed from the original source of information (hence farther than the 'tertiary generation' away from the primary source), and may not have fully explained the details. Sorry I didn't write my post clearer. Hope this helps.

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What I meant is that the sources I looked at seem to say that cable providers have to compress the signal whereas the over-the-air broadcasts do not, with respect to the lossy vs. lossless types.

Not to belabor the point more than I already have, but your sense of it is correct.

Our OTA signal is better than the cable version, and that's likely because it's further compressed at the cable end.

Not to confuse things further, but for us anyway, this is a reversal of the way things stood under analog.

Our transmitter, like a lot of analog transmitters, didn't kick out a signal anywhere near as good as what we passed to the cable co., nor what the cable co. then put on analog cable.

s/

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What I meant is that the sources I looked at seem to say that cable providers have to compress the signal whereas the over-the-air broadcasts do not, with respect to the lossy vs. lossless types.

There is no lossless, and GENERALLY, I repeat GENERALLY cable does compress more, in the transcoder.