HD vs. HR

[The Computer Audiophile]

I've been thinking lately about the general public's reaction to high resolution audio versus its reaction to high definition video. When I first demonstrated the difference between standard definition broadcast video at 480i versus high definition broadcast video at 1080i my mother and my wife immediately noticed how much better the HD version looked. We were watching the Grammys several years ago and Beyonce was wearing a very sparkling costume. The clarity of the costume was immediately identifiable to both of them and I'd venture a guess this was easily seen by anyone with somewhat clear vision. My wife and mother instantly made up their minds that HD was much better than SD.

 

If I were to attempt this type of demonstration using standard definition audio, say Redbook CD at 16/44.1, and high resolution audio at 24/192 neither of them would hear a difference. I'll bet the farm on it.

 

However, is this a fair apples to apple / oranges to oranges demonstration. I honestly don't know. What I'm interested in knowing is this:

 

1. What is the audio equivalent to 480i (from a technical point of view)?

2. What is the audio equivalent to 1080i (from a technical point of view)?

 

If the answer to question 1 is 16/44.1 and the answer to question 2 is 24/192 then we are back at the age old debate that most of us need a rest from. For some reason I think the technical equivalent of 480i would be much lower than 16/44.1. When I say technical equivalent I mean numbers, not marketing terms like SD and HD etc… What if 480i = 8/22.05?

 

It follows that an interesting listening test could be conducted with people listening to the equivalent of SD video versus the equivalent of HD video. I'm not sure if this proves anything but it would be an interesting piece of data to possibly combat marketing terms.

 

As I said, I don't know the answers and need help determining if this is even plausible or doesn't even make sense. Don't worry about hurting my feelings with honest posts :~)

[InfernoSTi]

I would say that regular broadcast quality is MP3 level…good enough for everyone but not as good as high def once you see it.

 

For me, early high def (720p, etc) was more like CD quality (16/44). It was a real step up from standard broadcast just like CD lossless is a real step up from MP3.

 

I would say 1080i is more like 24/48 or higher. Once you get to that level, it all depends on the source recording (film or audio).

 

Really good source material is much better at 1080i while lesser material is about the same at 720p or 1080i…and sometimes a standard def source is better at 480i just like some CDs are better than (or at least not worth going to) high res.

 

In my experience, this is how things shake out…

 

Best,

John

[mayhem13]

I bet you're right about the difference from Redbook to HiRes for average listeners or non enthusiasts....I know nobody in my home seems to care! Lol

 

I'm not convinced that resolution in audio has the same visceral impact as a dynamically capable system. If you can hit 20hz smooth with authority all the way to 16khz relatively flat and dynamic peaks above 100db with no thermal compression or induced distortion, even an 320kps MP3 gets people all fired up.

 

For me, it's always been the dynamics and clarity.....resolution simply isn't a major priority and certainly not for my guests when we host a movie night in our theater. Many classic DVDs are simple stereo where my processor will deliver a 5.1 mix.....speech intelligibily is sub par, effects rolloff around 10khz, ......but deliver the thumps and startle em with 1-2kw of unbridled current......Wow!

[Jsmith]

I agree this is very hard to define. I would like to put something else up for consideration.

 

What about DR? Many people seem to think that low DR is immediately bad. A file that is 24/96 with DR 6 is not considered HD. In some cases we may all agree it is bad. In others, I think the artist can use it as an artistic tool to change the sound.

 

If we go to your video analogy I propose the following. Schindler's List was done in black and white. You can buy it in HD, but everyone would have to admit that by going black and white something was left on the table (HD Color) for the sake of artistic interpretation, and it was considered genius.

 

If we apply the Schindler's list comparison to music, you could say that a file with more bits (24/96) but low DR due to artistic choice, is still HD.

[esldude]

Arguably HD video is not equal to good redbook in some terms. Redbook basically gets frequency response, noise, distortion etc to levels not discernible to humans. What it may lack in terms of complete fidelity is very small things at the margins. Differences audio on the best of equipment and recordings is not in absolute terms very large at all. Even stereo comes closer to 3D audio than 3D video does to real life.

 

HD video was a roughly doubling of resolution, and one clearly obvious. It still comes up short of dynamic range.

 

I would rate HD video about equivalent to moderate bitrate MP3. Probably better than 128k mp3, maybe equal to 240k mp3.

 

To equal roughly SD video in my opinion you might be looking at cassette tape without noise reduction. And that probably would not include top tape decks like those from Nakamichi. Something with 8 bit resoultion and 125 hz-8 khz bandwidth. Plus listening over small speakers. This I believe would roughly equal SD as seen in basic DVD quality.

 

The problem isn't that people don't appreciate quality audio. The problem is audio equipment is too close to perfect compared to a still imperfect video. The big #1 thing that would involve people in audio more is really good speakers/headphones not costing a fortune or looking like a spaceship. What audio they have is usually hampered hugely by the playback device. Showing a complex sound system to someone with big speaker makes them think they need it all. Some pretty pedestrian equipment with good speakers will get you almost all the way there. Please note I am not saying the other stuff doesn't matter, just nowhere nearly as much as speakers.

 

Then the final thing is how much people like video. 90% of our total sensory input is through our eyes. Ears are a bit under 10 %.

[The Computer Audiophile]

Arguably HD video is not equal to good redbook in some terms. Redbook basically gets frequency response, noise, distortion etc to levels not discernible to humans. What it may lack in terms of complete fidelity is very small things at the margins. Differences audio on the best of equipment and recordings is not in absolute terms very large at all. Even stereo comes closer to 3D audio than 3D video does to real life.

 

HD video was a roughly doubling of resolution, and one clearly obvious. It still comes up short of dynamic range.

 

I would rate HD video about equivalent to moderate bitrate MP3. Probably better than 128k mp3, maybe equal to 240k mp3.

 

To equal roughly SD video in my opinion you might be looking at cassette tape without noise reduction. And that probably would not include top tape decks like those from Nakamichi. Something with 8 bit resoultion and 125 hz-8 khz bandwidth. Plus listening over small speakers. This I believe would roughly equal SD as seen in basic DVD quality.

 

The problem isn't that people don't appreciate quality audio. The problem is audio equipment is too close to perfect compared to a still imperfect video. The big #1 thing that would involve people in audio more is really good speakers/headphones not costing a fortune or looking like a spaceship. What audio they have is usually hampered hugely by the playback device. Showing a complex sound system to someone with big speaker makes them think they need it all. Some pretty pedestrian equipment with good speakers will get you almost all the way there. Please note I am not saying the other stuff doesn't matter, just nowhere nearly as much as speakers.

 

Then the final thing is how much people like video. 90% of our total sensory input is through our eyes. Ears are a bit under 10 %.

Thanks esldude. This is the type of info I'm looking for. If correct, I wonder if "average" people could tell the difference between 8 bit resoultion and 125 hz-8 kHz bandwidth and "128k mp3, maybe equal to 240k mp3"? Conversely, I wonder if people could tell the difference between UltraHD (4K) and 8K from 10 feet. Don't know.

[sdolezalek]

Seeing and hearing are both multivariate senses. In seeing there is resolution, dynamic range, jitter (for moving images) color fidelity and spectrum range and probably a few others that don't now come to mind. In hearing we also have resolution, dynamic range, jitter, frequency fidelity and range and others as well. As to each variable there must be a point of diminishing returns on further improvement (i.e. will 4k televisions be the 192khz?) Then too there is 3D television, which like 5.1 surround sound adds some benefits but also adds complexities that then separately need to be solved to bring that upgrade close enough to 2D in reality to really be seen as a benefit.

 

It feels as though we are getting pretty close to the flat part of the curve (where the cost/difficulty of further improvement exceeds its tangible benefits) on most of the variables that apply to video; but I don't think we are quite at the confusing a screen for a window stage yet (pretty close though).

 

In audio, I wonder whether our sensitivities to each of these variable is different (i.e. humans are more sensitive to some than others and these sensitivities differ from sight) and whether we are as close to approaching those diminishing returns.

 

So rather than just comparing SD/HD video and SD/HD sound; is there a way to compare good to best available across each of the variables in order to get a better sense of where in audio we are falling the furthest from ideal? In other words, we may be at 98% in resolution, 92% in dynamic range, 90% in jitter, but 99% in frequency response, etc. I know that particularly in audio there is somewhat of a zero sum problem in that improvements in one dimension may necessitate compromises in others, but it would be interesting to better understand the domain in which we fall shortest.

[Savage]

Perhaps 16/44 on a vintage CD player vs Hi-Res from dac & computer. I don't think it's as much about the rates as it is overall improvement.

 

HDTV has been around/popular 20-25 years even by conservative estimates and has improved greatly. I preferred 480i to many of the early HD sets. Smoother, faster and better color fidelity took a while at human prices.

 

I understand where picking some demo material by the numbers would be appealing and easy to communicate. It doesn't seem to tell the real story though.

[The Computer Audiophile]

So rather than just comparing SD/HD video and SD/HD sound; is there a way to compare good to best available across each of the variables in order to get a better sense of where in audio we are falling the furthest from ideal? In other words, we may be at 98% in resolution, 92% in dynamic range, 90% in jitter, but 99% in frequency response, etc. I know that particularly in audio there is somewhat of a zero sum problem in that improvements in one dimension may necessitate compromises in others, but it would be interesting to better understand the domain in which we fall shortest.

Very interesting.

[sandyk]

Chris

Although Australian TV has HD 1080i capability, only a few channels use it. This is disappointing because having seen some of the material you guys can watch from the likes of David Letterman etc. and especially with some of the guest musicians, I feel we are being short changed ,because the majority of Aussies now have HD capable TVs. Some of this material captured and posted on the Internetis absolutely fabulous compared with standard DTV, and the 5.1 audio even when converted to stereo can be very good indeed and sound quite a bit better than the same music from CD.

I am not sure that the change from .mp2 to .mp4 has been beneficial though, as it often results in slightly lower visual standards due to perhaps trying to use the gained bandwidth for additional lower resolution channels by using lower than optimum bit rates??

I am not suggesting that .mp4 is inferior, but perhaps they are trying to take the savings too far ? This is how it appears to an outsider, and I could be quite wrong about this.

I am envious of what you guys appear to take for granted, when one of our ABC channels ( Government funded) is used mainly for 24 hour news in HD. The picture quality is of course way better given suitable material though.

 

Regards

Alex

[esldude]

Chris

Although Australian TV has HD 1080i capability, only a few channels use it. This is disappointing because having seen some of the material you guys can watch from the likes of David Letterman etc. and especially with some of the guest musicians, I feel we are being short changed ,because the majority of Aussies now have HD capable TVs. Some of this material captured and posted on the Internetis absolutely fabulous compared with standard DTV, and the 5.1 audio even when converted to stereo can be very good indeed and sound quite a bit better than the same music from CD.

I am not sure that the change from .mp2 to .mp4 has been beneficial though, as it often results in slightly lower visual standards due to perhaps trying to use the gained bandwidth for additional lower resolution channels by using lower than optimum bit rates??

I am not suggesting that .mp4 is inferior, but perhaps they are trying to take the savings too far ? This is how it appears to an outsider, and I could be quite wrong about this.

I am envious of what you guys appear to take for granted, when one of our ABC channels ( Government funded) is used mainly for 24 hour news in HD. The picture quality is of course way better given suitable material though.

 

Regards

Alex

 

I guess we do take it for granted. On my cable feed I have the program guide set to only show HD channels. Too hard to go back to SD. Maybe audio cassette still isn't as degraded as SD video. I still at times enjoy cassette tapes in an older car I have.

[sandyk]

I guess we do take it for granted. On my cable feed I have the program guide set to only show HD channels. Too hard to go back to SD. Maybe audio cassette still isn't as degraded as SD video. I still at times enjoy cassette tapes in an older car I have.

 

Dennis

Perhaps part of the problem is the cable feed ?

We also have Foxtel via Broadband cable for the rest of the family, but I much prefer the Free to Air transmissions for their superior clarity, even with SD. It appears that a SD FTA transmission where the source was down converted from the original HD camera source of some local productions, can look much closer to that of a HD transmission.

Very few HD MTV clips appear to have anywhere near the same clarity of that from your late night shows.

The occasional Vevo or Youtube music video in 1080i that is downloaded and played can look pretty decent though, although I can hear the minor shortcomings of 16/44.1 .aac audio encoding compared with that of similar on CD.

Check out some of the Bridgit Mendler clips labelled "Acoustic"

Alex

[DigiPete]

Absolutely non-scientific:

 

480i ≈ 128kbit/s mp3 stereo

1080i ≈ 320 kbit/s 5.1 (Dolby AC-3)

 

As said before - sound does have so many dimensions.

[pooger]

When I looked at larger TVs, 1080ps were just coming in. I diligently printed out a black and white pixel grid at 1080 and 720 to see how close I'd need to sit to a 60 inch set for the pixels to become visible—and this was the worst case—ultimate contrast, no motion to distract, etc. I needed to be closer than 4 1/2 feet (not great eyesight, but my wife with eagle eyes was at about 6 feet). I still went for the 1080. Factors like black level and motion blur, etc. all seemed more critical to getting a great image than the resolution once you were at a clean 720. (Set we got was a Pioneer Kuro Elite, and I still enjoy of the picture quality.)

 

I think I'd need to put cotton in my ears to muffle the sound from even an mp3 played on a good system, to get it to be analogous to the SD - HD comparison. Certainly in someone's ears that is not used to listening to a good sound system. People that come over don't seem to notice soundstage or micro-dynamics unless I coach them through the process—but everyone "knows" how to look at things. As in an earlier post, it's dynamics and clarity (even the level that you get from 320 mp3s, using an iPod as the source), that people seem to notice and go wow over. Maybe a cassette would be right, but I think a decent table radio, say like a Bose (decent is relative here) as the SD equivalent works. It's the other aspects of our good systems that people notice, not their resolution.

[NOMBEDES]

I can see jitter on my TV.

 

I have never heard jitter on any of my audio systems.

[realhifi]

 

Then the final thing is how much people like video. 90% of our total sensory input is through our eyes. Ears are a bit under 10 %.

 

Important point. Try this experiment. Take a small audio recorder out to lunch and record your conversation. As you are talking take time to notice that your conversation seems easy (if in fact the restaurant isn't TOO noisy that is) and that following along without distraction seems fine. Then later pull out the recorder and play back the conversation and see how much noise and clutter seemingly at almost the same volume there is. The recorder is unable to filter things things out that the ear, eyes and brain do naturally and easily.

 

Our ears and brains are remarkable instruments and so much better at discerning things than a machine ever will be.

 

I do however think that percentage figure might be closer to 80/20 in favor (of course) to the image. Only problem is that the cost is skewed in the other direction if you really want that enveloping experience. And most folks will just not go there. Say in one system I have where I have a great 60" plasma that I purchased for less than a grand but the receiver, subwoofer, front speakers and surrounds came to around $5,500. To me it feels pretty balanced and certainly not overkill on the sound side.

[realhifi]

Absolutely non-scientific:

 

480i ≈ 128kbit/s mp3 stereo

1080i ≈ 320 kbit/s 5.1 (Dolby AC-3)

 

As said before - sound does have so many dimensions.

 

That sounds about right with Blue Ray disc closer to 16/44.

[Daren F]

I would say that:

 

FM radio = 480i

16/44.1 Redbook CD = 720p

24/96 hires = 1080p

 

I have a 106" HD projection system and I still find it hard to tell the difference between 720p and 1080p videos. Much like 16/44.1 vs 24/96 audio. In the end it all comes down to the quality of the recording.

[mwheelerk]

Very interesting. I had an experience recently with a friend. My friends focus is video and audio as primarily been a means to deliver the sound of movies. He does listen to and enjoy music but it was from his very small desktop speakers or from earbuds and his iPod as he exercised.

 

I met him in 1997 and was very impressed that he had a three year old 64" wide screen TV. Wide screen and 64" TVs were definitely not prevalent, at last in my neck of the woods, in 1994. Well it's 2014 and he just, just got an HDTV, a 75" inch Samsung. Along with that he updated his old, but not quite as old, audio system.

 

He had been over to my place numerous times and liked the functionality of my computer based system. So we added an Apple TV and got his library streaming. Obviously he was blown away by the quality of the video presentation.

 

Something interesting happened though on the way to playing the music from his iTunes library. The first few songs sounded okay to him. He skipped through pieces of a number of songs listening and seemingly satisfied. Then he selected another song and a sudden wow came over him how awesome it sounded. I asked him if I could pick a few songs. I picked a few selections and his wows continued. I then switched between his selections and a couple I selected and each time he significantly preferred my choices in terms of sound quality. When he asked me why I told him I thought I knew the reason and we went back to his office and looked at the files. Each one he had picked was either imported or downloaded as an mp3. Each one that I picked was an imported ALAC file. I knew which ones to pick because about three years before I had showed him how to import CDs into his library. I imported those particular files myself for him. He had changed the settings to mp3 for the imports he did and the rest he downloaded as mp3. He immediately heard the significant differences on his new system.

 

My buddy is now in a forced march to re-import all his CDs and even deleted over 5000 mp3 from his library because they took away from his listening pleasure. I get a text almost every night about how this or that sounds so great. He tells me he has not listened to so much music in years.

 

I guess I think mp3 = SD and ALAC (in this case) = HD. Because of the limitation of the Apple TV I had not been able to compare on his system HR audio. I have compared it at my home to him but the differences for him were much more subtle if even apparent.

[esldude]

Important point. Try this experiment. Take a small audio recorder out to lunch and record your conversation. As you are talking take time to notice that your conversation seems easy (if in fact the restaurant isn't TOO noisy that is) and that following along without distraction seems fine. Then later pull out the recorder and play back the conversation and see how much noise and clutter seemingly at almost the same volume there is. The recorder is unable to filter things things out that the ear, eyes and brain do naturally and easily.

 

Our ears and brains are remarkable instruments and so much better at discerning things than a machine ever will be.

 

I do however think that percentage figure might be closer to 80/20 in favor (of course) to the image. Only problem is that the cost is skewed in the other direction if you really want that enveloping experience. And most folks will just not go there. Say in one system I have where I have a great 60" plasma that I purchased for less than a grand but the receiver, subwoofer, front speakers and surrounds came to around $5,500. To me it feels pretty balanced and certainly not overkill on the sound side.

 

The 90/10 split between vision/hearing wasn't my estimate. It was based upon the amount of information flowing through our senses as determined by research. Total sensory input is somewhere around 11 mbps. Right near 10 mbps is vision. About 900kbps for hearing, and the other senses around 100-120 kbps.

 

Now the processing that goes on with those input bitstreams is far in excess of that. One reason we probably have an easier time using a proxy for real vision is our much more highly developed pattern matching and processing of things visual. The lesser ability with sound means it has to be better for us to make do with it. Our even lesser abilities with other senses makes them even harder to trick in some ways.

[elcorso]

I trust more ears than eyes.

 

Ask a magician...

 

Roch

[firedog]

 

Just watch the McGurk effect video and it becmes painfully obvious that for humans sight is the dominant sense. No surprise that people notice the effect of HD video and not HR audio. Most of us simply aren't "trained" to hear that way, whereas we are naturally "trained" to notice small changes in visual signals.

[Harpy]

I don't think it's a fair comparison. Two channel audio reproduction was perfected in the 70's and it had it's digital age was well before the television. I don't think there would be the "wow" factor between 1080i and say some futuristic 3240i. One technology is very mature one is not. I would say 480i LP, 1080i a CD, and the futuristic 3240i is the SACD.

Please realize I am making a some very broad generalizations.

[crisnee]

SD video = pathetic (especially when viewed on LCD flat screens) 64 kb mp3 at best.

HD 720-1080i video = 128 kb mp3 at best (at least on your average flat screen tv)

 

HD is so much better than SD that we think it's great. It is not. Look at it closely, not too closely though as then you won't recognize anything. SD was so bad that even if you didn't look at it closely you could tell most of what you saw was illusion.

 

Chris

[Skeptic]

1. What is the audio equivalent to 480i (from a technical point of view)?

2. What is the audio equivalent to 1080i (from a technical point of view)?

I'm not sure that you can really make equivalents "from a technical point of view", and this may not be a popular opinion, but I would say that the "1080i" (or 1080p) equivalent would be the CD format.

Your old 480i video which doesn't look very good any more is every consumer format that came before the CD - cassette tapes etc. excluding vinyl records. (because I don't want to get into that debate)

 

Compressed digital formats like MP3 and AAC would be equivalent to "HD" streaming services or broadcast, compared to Blu-ray.

 

High resolution audio is equivalent to 4K and 8K video - where you are starting to see people saying that they don't really notice the difference, or that they have to buy a big television or get really close to the screen to see the difference.

 

But there's no equivalent to "sitting closer to the screen" or simply buying a bigger TV that I can think of for audio, to amplify the differences between "HD" and "Ultra HD" content.

 

What about DR? Many people seem to think that low DR is immediately bad. A file that is 24/96 with DR 6 is not considered HD. In some cases we may all agree it is bad. In others, I think the artist can use it as an artistic tool to change the sound.

I would say that this is the equivalent to HD releases which have lots of noise reduction applied to remove any trace of film grain from the image, and a lot of sharpening to make the image "pop" even if it introduces all sorts of nasty artifacts in the image.

 

There are a number of releases on Blu-ray where this has been the case, and you have the videophiles saying that the transfer to HD was terrible, and the "average joe" saying it looks great because they don't know any better.

 

One example which stood out to me, not because I think it's a particularly good film, but because opinions were so polarized, was Crank on Blu-ray. The videophiles hated how that film looked - it was a terrible one-star quality transfer.

The "average joe" loved how that film looked - it scored 5/5 for video quality on a lot of review sites.

 

Another example might be Avatar, which I would say was a 2/5 for quality on Blu-ray - it uses an awful lot of noise reduction and sharpening, which looks really bad from a technical point of view.

But people loved all the vivid colors and the imagery that was being shown on-screen, equated that to "image quality" and again it got a lot of 5/5 scores on review sites - which I would say is a pretty good comparison to a "high resolution" release that only has a dynamic range of 6 being praised because the music is good, even though the objective mastering quality is poor.

 

The thing is - if you want the video to "pop" like these bad film transfers, most televisions and players have noise reduction and sharpening options. It's easy to make a really nice video transfer look that way, if that's what you want. But you can't do anything to undo those artifacts when it's encoded into the disc itself - just like dynamic range.

 

You can always enable a dynamic range compressor in your player or on your AVR, but you can't get back what has been lost if you're starting with a file which has already been heavily compressed.

 

I can see jitter on my TV.

I'm curious to know what you mean when you say that you can "see jitter" on your TV.

Depending on what it is that you're seeing, there's a good chance that there's a solution for it.