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Are CDs lossless?, Evolution of my are WAVs lossless thread
upNorth
post Aug 1 2003, 11:58
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To hear how differences between people can affects things, The CIPIC HRTF Database for binaural recording is interesting to play with, to hear how differences between people plays a role concerning perception. You need MATLAB to use it though.

Btw: I think AtaqueEG has described this thread very well already smile.gif
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2Bdecided
post Aug 1 2003, 13:43
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QUOTE (upNorth @ Aug 1 2003, 10:58 AM)
To hear how differences between people can affects things, The CIPIC HRTF Database for binaural recording is interesting to play with, to hear how differences between people plays a role concerning perception. You need MATLAB to use it though.

But to suggest that this shows that different people perceive things differently is misleading. I'm sure people do perceive things differently, but different HRTFs do not prove this - in fact, if anything, they suggest the opposite...


We all have different shaped ears - that's simple biology. That's why we have different HRTFs. BUT our brains decode those HRTFs to give us an impression of spatial location. Our brains decode our own HRTFs, so that the sound coming from our ears sounds normal to us. Everyone else's ears are doing the same for them.

If you listen with someone else's HRTFs, your brain is still trying to decode your HRTFs, so the results just sound plain weird, or wrong. But what you hear in this experiment is not what the other person hears - when they use their ears with their own HRTFs (obviously!), their brain decodes their HRTFs and it sounds normal [i]to them/i].


So, the differences due to different shaped ears are removed by the brain, allowing different people to hear, or at least experience, similar things for a given external sound source.

When you inject the source straight into the ear (e.g. using headphones, so bypassing the pinna, and hence HRTF), that's when it gets weird.

Also, if you accept that people know what a sound at, say, straight ahead should sound like to them; and they also know what a sound at, say, 30 degrees left should sound like, then it's clear that real sources at either location will sound like they are, well, exactly where they are! BUT a phantom source created by two loudspeakers (e.g. stereo) may not sound the same to all people, because what the HRTFs are adding, and what the brain is subtracting, are not the same. so the illusion of a central source hanging between two loudspeakers may not work equally well for different people.

Which brings us back to the lossless idea: if you can re-create the sound field that was in the original recording space (within certain parameters of accuracy); not a trick or illusion of it, but the same air movements, then any differences between different listeners won't matter.


What a thread! It all begs the question: what do things sound like to other people? And what do things look like? How do you know that, when I see green and when you see green, we both see the same thing? The relevance to this is that, if you make a perfect copy of a green piece of paper, the copy will still look green to everyone. If the copy changes the colour slightly, then different people's perception of the change will be different. That's why any lossy process is so subjective.

Cheers,
David.
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Halcyon
post Aug 1 2003, 14:05
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QUOTE (keLston @ Jul 31 2003, 10:42 PM)
Given that... are CDs lossless?

This would mean because CDs are at 16/44.1k (I think?), there is quite a bit of data that is lost. Unless you define lossy, as compression.


Your question is a very good one and you are clearly trying to understand the theories of sampling and quantisation in intuitive terms. That is good. Please feel free to ignore those that mock you or your questions. They have clearly forgotten what it was to be a novice in a specific domain smile.gif

In signal theory terms, any real working implementation (not just a theoretical mathematical formula) from analog to digital (consisting of both sampling and quantisation) and back to analog is inherently lossy. This is more often the case, if analog signal is not frequency (or more generally bandwidth) limited, but holds true even if it the analog signal is bandwidth limited.

Most people who blindly quote Shannon fail to understand that what works in infinite time in calculus may not work in real-time in a dsp. So, in practise the situation is a little bit worse than in theory (yes, even for sampling only sans quantisation and back to analog).

Now, do analog to signal digital conversions in general have practical audible implications in bandwidth limited audio ment for human consumption?

Sometimes yes, at least for sampling rates much below 44.1 Ks/s and/or word lengths much below 16 bits. However, CD bandwidth at 44.1 Ks/s and 16 bits is sufficient in terms human hearing to capture a good (if not theoretically perfect) audio signal that has been digitized from an analog source.

Whether this can be audibly improved upon (for human listeners) by increasing either the sampling frequency and/or the quantisation space, well... that's a very heated debate. Quite many seem to believe that things can be improved by upping sample rate / bit depth, although some think it's a waste of bits in terms of engineering and what are the practical limits of audio reproduction in most circumstances. That is, some consider that we can't even get anywhere near the 44.1kHz / 16-bit theoretical maximum performance out of our state of the art playback equipment (in an ordinary listening room), so it's not perhaps wisest to try and fix playback problems by increasing sample rate and bit depth in the signal.

However, most seem to agree that a higher sampling rate and longer word length has practical and audible benefits for audio archival and for later processing of the digitized audio signal in such a manner that the processing artifacts do not become as easily audible as they would come with a 44.1khz/16bit original signal.

As to the "is CD lossy" question, that can be answered in many ways. My personal stance is that no, CD is not lossy. The digitisation of analog signals for CD use purposes is often lossy (for good practical reasons). So, the complete preparation of analog material for digital distribution is lossy: microphone recording, pre-amplification, mixing, sampling/quantisation, production, mastering, etc. These all lose information in signal theory terms, when compared to the original analog waveform of an acoustic space in which the recording was done.

However, the transfer of 44.1 Ks/s / 16-bit digital signal to CD does not (and most often is not) lossy. It's just (practically, in terms of data retrieval) a perfect transfer of bits onto a medium that can be re-read over and over again and still get the exact same bits out (practical limitations apply).

As to your lossy chain question, I'm completely lost smile.gif

As to the implied "is CD enough" question. I'm not going to touch that with a ten-foot pole smile.gif

Best regards,
Halcyon

PS Do not feel afraid to ask questions that you feel are important or hard to answer yourself. If you don't get an immediate answer, move on and ask elsewhere. Try to set up your own working hypothesis (just as you did above) and try to improve it with others. You'll learn much better by asking questions, trust me (yes, I have some background in educational sciences, so I feel confident in my recommendation).

This post has been edited by Halcyon: Aug 1 2003, 14:09
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Curi0us_George
post Aug 1 2003, 15:09
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QUOTE (Halcyon @ Aug 1 2003, 05:05 AM)
In signal theory terms, any real working implementation (not just a theoretical mathematical formula) from analog to digital (consisting of both sampling and quantisation) and back to analog is inherently lossy. This is more often the case, if analog signal is not frequency (or more generally bandwidth) limited, but holds true even if it the analog signal is bandwidth limited.

I feel that's misleading. A pure 10 Khz sine wav count be perfectly captured onto a CD with no loss. That's a rather manufactured example, but you can move from there into more realistic applications, too. A lot of audio can be perfectly captured in 16/44.1.
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2Bdecided
post Aug 1 2003, 15:20
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QUOTE (Curi0us_George @ Aug 1 2003, 02:09 PM)
QUOTE (Halcyon @ Aug 1 2003, 05:05 AM)
In signal theory terms, any real working implementation (not just a theoretical mathematical formula) from analog to digital (consisting of both sampling and quantisation) and back to analog is inherently lossy. This is more often the case, if analog signal is not frequency (or more generally bandwidth) limited, but holds true even if it the analog signal is bandwidth limited.

I feel that's misleading. A pure 10 Khz sine wav count be perfectly captured onto a CD with no loss.

But there will either be noise or distortion about 90dB below digital full scale. It's not a perfect representation of a pure 10 kHz sine wave because there's other stuff at other frequencies (all be it very quiet) which should not be there.

btw, Halcyon, that's a nice, patient explanation - but he did have the question answered - it's in the FAQ, to which he was directed.

Cheers,
David.
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upNorth
post Aug 1 2003, 16:49
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QUOTE (2Bdecided @ Aug 1 2003, 02:43 PM)
QUOTE (upNorth @ Aug 1 2003, 10:58 AM)
To hear how differences between people can affects things, The CIPIC HRTF Database for binaural recording is interesting to play with, to hear how differences between people plays a role concerning perception. You need MATLAB to use it though.

But to suggest that this shows that different people perceive things differently is misleading. I'm sure people do perceive things differently, but different HRTFs do not prove this - in fact, if anything, they suggest the opposite...

As always you know what you are talking about smile.gif
I can't see what I wrote that was wrong, but in the context of this thread I guess it could be misinterpreted.
To make it clear, I agree with what you say, and this wasn't ment as an example of how people perceive things differently. I tried to give an example of how things that works for one person doesn't work for another. In this case a HRTF. The goal is as you say, to make both perceive the same thing, but that may not work if the HRTF generated with person A is used with person B. As person B's hearing is trained with his own body/HRTF. As you also say it's hard/impossible to say if they do in fact perseive the same thing anyway, but differences between people affect the training process. Hence you can't just change things that has been a part of this process.

Not sure if I manage to communicate what I try to say, the part quoted above tells me I don't, but I think I have the understanding of it anyway.
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KikeG
post Aug 1 2003, 17:27
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In my opinion, something like 24/50 (or maybe 24/48) if properly implemented, is lossless from the ear point of view, under any circumstances, because the dynamic range and bandwidth achieved match or are over than what the human ear can perceive, even over the most demanding situations and the best golden ears.

24/44 maybe could not match hearing of people that can hear isolated ultra-high tones, people that could be say, 0.01% of people, and very young people. But it would be surely enough in my opinion for real world music, where those isolated tones don't exist, or are too soft to be perceived.

16/44 doesn't match max. possible dynamic range of human ear under any circumstance, that is, from the threshold of audibility to the threshold of pain. But it does indeed match the dynamic range of real-world and practical listening, since our listening rooms have noise that is quite over the threshold of audibility, and because nobody in practice gets even close to the threshold of pain when listening for pleasure.
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Halcyon
post Aug 1 2003, 19:22
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QUOTE
So, the differences due to different shaped ears are removed by the brain, allowing different people to hear, or at least experience, similar things for a given external sound source.


That is an interesting claim, but I cannot find scientific evidence to support your claim (there could easily be some, I'd like to know if there is). The whole hearing apparatus (including muscular coding in middle-ear and basilar membrane + hair cells in inner ear and neurochemical pathways to thalamus and onto cortex) does adapt to signals being fed to them (both over time and almost instanteneously)

This is not AFAIK the same as "remove the differences due to different shaped ears". Especially if we are talking about high level cognitive auditory perception, rather than low level auditory evoked potentials. Perception remains invariably a subjective experience, as you have stated.

Or have I completely misunderstood you (there's always that possibility) smile.gif

QUOTE
When you inject the source straight into the ear (e.g. using headphones, so bypassing the pinna, and hence HRTF), that's when it gets weird.


Err... how do you do that? With ordinary headphones you still get the coupling to head and pinnae and ear canal. Although you lose torso and head occlusion to some degree (depending on headphone construction), you don't "bypass HRTF".

Even for canalphones (say Etymotics) the ear canal acts as a (somewhat closed) resonant chamber and as we know, the length of ear canal is not standard from human to human.

Did you mean something else (again)?

I have other comments to various other parts of your wonderful post (including direction discrimination and perception invariance), but have to leave my own comments truncated due real-life calling.

Good thread! Keep the discussion alive and we all learn.

cheers,
halcyon

This post has been edited by Halcyon: Aug 1 2003, 19:24
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Halcyon
post Aug 1 2003, 19:38
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QUOTE
KikeG
In my opinion, something like 24/50 (or maybe 24/48) if properly implemented, is lossless from the ear point of view


This could well be (to a statistically large enough degree), but AFAIK currently it's easier to get near 16-bit resolution out of a 24-bit implementation and better amplitude linearity with 96kS/s than 44.1 KS/s for the usable human hearing range.

With higher bit-depth and and sampling rate we can skip some real-time imperfect bandwidth transforms (such as the current de facto multi-bit delta sigma oversampling with requantisation and dither) that are a must have for most inexpensive 44.1kHz/16-bit implementations that try to achieve the theoretical and audible limits of the format.

QUOTE
16/44 doesn't match max. possible dynamic range of human ear under any circumstance, that is, from the threshold of audibility to the threshold of pain.


I agree, although there are other benefits to a higher word length (mostly signal processing/conversion related as above).

Furthermore, to press your point, nobody has the full 120+ dB range of hearing available at one instant in time. Dynamic range in hearing just as in vision is compressed to a usable range for a given signal detection situation. It is smaller than the whole maximum range and adapts based on the signals being sensed. For example the acoustical reflexes of middle and inner ear ensure that nobody will hear much anything from a 20 dB signal for at least a few seconds after a 100 excitation. So, the dynamic range at any time is less than 120 dB and as such will further prevent us from hearing all the limits of 16 bit audio, even though we can detect signals well below the (static random) noise floor of acoustical spaces.

regards,
Halcyon
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KikeG
post Aug 1 2003, 20:55
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QUOTE (Halcyon @ Aug 1 2003, 07:38 PM)
This could well be (to a statistically large enough degree), but AFAIK currently it's easier to get near 16-bit resolution out of a 24-bit implementation and better amplitude linearity with 96kS/s than 44.1 KS/s for the usable human hearing range.

With higher bit-depth and and sampling rate we can skip some real-time imperfect bandwidth transforms...

Yes, but I'm talking about resolution of media, not converters. Good 24-bit converters achieve near-theoric 16-bit performance when playing 16-bit audio. Also, I wrote 50 KHz sampling frequency to leave some room for real-world imperfections of converters in regards to their hf roll-off.

QUOTE
I agree, although there are other benefits to a higher word length (mostly signal processing/conversion related as above).


But this higher word length is only needed at the editing stage and inside the converter, not in the media.

I't interesting what you noted about instantaneous dynamic range of human ear, this reduces further the practical requirements of digital reproduction systems.
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Pio2001
post Aug 1 2003, 21:04
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Wow ! It makes HDCD's dynamic gain a smart way to handle dynamics : to code a gain setting along with the PCM data.
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Heaven17
post Aug 1 2003, 22:39
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"What a worthy and useful thread. "

"I don't even know where to start "

"Without getting all cranky, I would suggest you go out and do some reading before starting any more "profound" threads like this one."

"Obviously (well, at least to me) we are not concerned with that on this page. We are concerned with "psychoacoustic audio compression". Please for godsakes read up on some audio basics. "

"Is there any actual point to this, Mr. ? Or are you trying to out-l33t somebody? This is like asking what is the sound of one hand clapping (ABX'ed, please) or how many angels fit on a pin's head."

"I mean, anybody who was made some research knows that NO format, maybe ever, will be Lossless in relation to the originally produced sound (the artist performance, that is)."

"Either deal with it or don't. Just don't try to play smart here."

"(I am really making an effort here...counting: 1,2,3,4,5...) "

"Anyway, I think this thread is more lossy than CD audio will ever be."

"I have a headache...I'm gonna go find some aspirin now..."

*****************************************************************

Well, what a delightful bunch you all are.

At some stage in our lives, most of us realise that other people don't always act in *exactly* the way that we would like. They may say things that annoy, upset or frustrate us, but sooner or later we come to realise that 99% of the time, this was out of simple ignorance or failure to understand rather than a deliberate attempt to cause offence. We learn this quality called "tolerance," which allows society to function in an imperfect world full of fallible, imperfect individuals who do not have absolute knowledge of everything under the sun.

This process is often called "growing up." A pity so many people on this board never seem to manage it.

Thanks and goodbye.
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F1Sushi
post Aug 2 2003, 00:03
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QUOTE (rjamorim @ Jul 31 2003, 05:11 PM)
What a worthy and useful thread. >_<

My sentiments exactly...

headbang.gif
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ScorLibran
post Aug 2 2003, 02:28
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QUOTE (sthayashi @ Jul 31 2003, 06:11 PM)
Also, this was more to try and draw some parameters from the original question, how far back in the recording/processing mix before you get to lossless (essentially).

This thread is not the easiest one to follow, but after reading more of the FAQs and other links posted previously in this thread, it still seems to me that the point in the recording process at which the audio has its last "lossless moment" is just before the sound hits the microphone, and just before the first electron enters a recording device from any electric instrument's signal processor. This is being discussed to death, I know, but it still seems to me that an analog recording would have the only chance to theoretically be lossless, but likely could never be in a real-world situation. I would still contend that digital, by it's nature, cannot be lossless. If digital could record sound without sampling the sound, then it could have at least a chance of being lossless.

QUOTE (2Bdecided @ Aug 1 2003, 06:26 AM)
Any recording of the electrical signal which comes from a microphone, whether that recording is analogue or digital, is lossy. However, you can put bounds on what you lose in a digital system. Sample two million times per second, and all frequencies up to one million cycles per second (i.e. 1MHz) will be stored - since the ear can only hear up to 20kHz, that's overkill - certainly lossless as far as human hearing goes!


I am without a doubt a newbie here, and I defer to your knowledge and references on this matter in all ways except on one issue. I would think that no matter what bounds you put on what's lost in a digital system, the fact remains that something is lost. Even if no human ear could ever hear it. My only point is that once that happens, the term "lossless" would never again apply. If any part of a sound is lost, but still "lossless as far as human hearing goes", it's still *not* lossless. My only point that differs here is that "lossless" is a sacred word with an absolute definition in the realm of recorded audio. One that effectively prevents it from ever correctly being used to describe recorded audio.

The concept of a recording being lossless as far as human hearing goes would imply that LAME --alt-preset insane is lossless to my ears, since I've never been able to ABX any sample I've tested with it. So if I truly cannot hear any difference between it and the original PCM WAV file, then is that MP3 format lossless to me? I argue "no", but it is, obviously, transparent. Those are the concepts that I think are getting overlapped too much in this thread. Lossless, by nature, guarantees transparency (and is part of what makes it a sacred term). Transparency can come from a recording format that is quite lossy, however, for the vast majority of people, such as from CD audio. Transparency is much easier to achieve than losslessness (is that a word?).

In the example you give of bounds in a digital system, if all frequencies up to 1MHz per channel are captured, I completely agree that it is overkill for satisfying human hearing abilities. But if there is one, tiny, menial, meaningless, but still existant frequency flaoting in the air in front of a microphone at 1,000,142 Hz, and if that frequecy was not captured on a CD, then the CD is lossy. Even if the thing lost can never, ever be heard by a human. It's still perfectly transparent, but it lost the title of "lossless" once any type of bounds were introduced.

I have no argument against the fact that "CDs are good enough". I think CDs are outstanding media, and I've never had a complaint about sound quality from one (except for crappy mastering, but that's a different issue entirely). But they still shouldn't be described with that giant, absolute, holy, sacred word: Lossless. That's all I'm saying. WAV to FLAC is lossless. Live to CD is not. (I'm not presuming to "teach" anyone here, as everyone in this thread likely has more technical knowledge than I do in these matters, I'm only using those as examples to communicate my point.)

And I honestly spent a good bit of time reading through the links you posted, and through other related information to try to educate myself as much as possible on the matter of CD audio, recording techniques, digital vs. analog, soundfield reproduction and everything else I could think to look up. But my argument is more philosophical than technical however, as I stand guard with vigilance in front of the word Lossless.

wink.gif
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cjanscen
post Aug 2 2003, 02:44
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A couple thoughts:

You can look at a CD-medium for distributing recorded music in two ways:

1) To reproduce, as faithfully as possible, the music that was recorded

or

2) To reproduce, as faithfully as possible, the music that the artist/group wants you to hear

Subtle differences I know, but in my opinion, good CD's are not just a recording of a band playing (exception: live shows). A band should use the studio and recording process to create something that is different (not worse or better, different) from what is heard at a live show....so in this sense the "goal" of a CD (distribution of music) does not have to be entirely about replication of what was heard in the studio that day.

And another point, think of a song you hear, and think of how it was recorded....it was tracked, dubbed, cleaned up, compressed, etc, etc...can the two even be compared (in terms of loss and losslessness)?
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ScorLibran
post Aug 2 2003, 03:53
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QUOTE (Heaven17 @ Aug 1 2003, 05:39 PM)
Well, what a delightful bunch you all are.

At some stage in our lives, most of us realise that other people don't always act in *exactly* the way that we would like. They may say things that annoy, upset or frustrate us, but sooner or later we come to realise that 99% of the time, this was out of simple ignorance or failure to understand rather than a deliberate attempt to cause offence. We learn this quality called "tolerance," which allows society to function in an imperfect world full of fallible, imperfect individuals who do not have absolute knowledge of everything under the sun.

This process is often called "growing up." A pity so many people on this board never seem to manage it.

Thanks and goodbye.

If you're joking then ignore this. If you're not...

To be honest, I don't see a major problem with this thread. It started as a likely argumentative (and possibly worn-out) topic, and a little bickering broke out, but so what. Maybe I'm subconsciously blanking out all the nastiness, but I think the majority of this thread is a valid, civilized discussion. Sure, my first post was one of sardonic humor, bound in abstract cynicism. blink.gif It wasn't the first time I've jumped into a thread with a semi-humorous (but respectful) protest, only to return later to join the discussion. And it certainly won't be the last time I do it. B)

And though I may differ on certain points with people here who I clearly acknowledge as smarter than I am about recorded audio, that's how people learn: communicate thoughts, listen to responses, learn facts, and change beliefs when appropriate. And then we share what we learn with others, and the cycle continues...

Anyway, a little bickering is just going to happen in an otherwise serious discussion. It's nothing to get in a fit over, as long as it doesn't become a flame war (which this thread is far from becoming IMO). If it were, a moderator would be in here handing out warnings, I'm sure. I think your advice of "tolerance" is valid, but it's already being used here.

If something in a thread breaks forum rules, report it. If you just don't like a thread, then don't read it. There! Problem solved!
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ger@co
post Aug 2 2003, 06:57
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"Lossy Audio Formats
The term "lossy audio formats" is used on audio formats [mp3, wma, ogg, etc.] that compress audio files by removing/filtering audio data. Once an audio file is converted to a lossy audio format, the original quality is lost forever (Reurich, 2002 d).

These are formats that compress audio files to an extremely small size and still sound good to most people. The bitrate is determined by how much data the file format is using for each second of audio-stream, and will also determine how good the quality will be. The higher bitrate, the better sound. If you want a near-CD quality, a bitrate of 128 Kbit/s should be suitable, but is also depending on the compression method used."

The above definition can be found here.

The key word here is compress. Now, with that in mind, is your (anyone's) argument still valid? biggrin.gif And, in answer to the original question, theoretically, as the arguments suggest, yes, but in following the definition of lossy audio, no.

Later.

This post has been edited by ger@co: Aug 2 2003, 07:09


--------------------
"Did you just say he contacts you through a bird? Did I just hear you say that?" Sonny Valerio (Cliff Gorman). Ghost Dog: The Way of the Samurai.
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ScorLibran
post Aug 2 2003, 07:23
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QUOTE (ger@co @ Aug 2 2003, 01:57 AM)
The key word here is compress.  Now, with that in mind, is your (anyone's) argument still valid? biggrin.gif

That's a good reference. I wouldn't presume doubting someone's definition of "lossy audio formats" without a valid argument, and I may sway in calling CD audio "lossy".

But I still can't call it "lossless" since it can't possibly capture all of the source audio data, the same way LPAC (for example) captures every bit of the data in a PCM WAV file (it's source audio data). The crux lies in the fact that a CD's source audio data is floating in the air (so to speak), and has severe inherent difficulties to capture all of it "perfectly"...it's technically not an infinite amount of data, but it's more than has ever been captured in a digital format. This same task is much easier for a lossless codec such as FLAC, LPAC or Monkey's since their source data is simply another file...reasonably finite and quantifiable.

From the same site, here's the definition of "lossless"...

Lossless audio algorithms return audio data that is identical to the original audio quality (Audio Box, Inc, 2000). This makes the file size generally larger than with lossy audio compression, and less useable for the Internet. With lossless audio formats you will see a reasonable file size decrease (usually around 30%) but not quality loss at all (Reurich, 2002 b ).

The core of my argument is that CD audio cannot return audio data that is identical to the original audio quality. I consider "identical" to be a word just as serious as "lossless", and would be very strict in it's definition. "Identical" means exactly identical, not just "sounds exactly the same to a human".

But thank you for linking a formal definition of these terms.

Hmmm...another consideration...

If we use only the Reurich definitions for a moment..."lossy" refers to only compressed formats, and lossless does as well. But uncompressed audio has to also be definable as either lossless or lossy, right? Or are these terms taken, and different terms are needed, perhaps?

[brief sarcasm=on]

If we need a new term to describe the integrity of CD audio, I vote for "Schmooo". CD audio is schmooo. All in favor? All opposed? See how easily we could resolve this debate? Just as long as no one talks about schmooo. (Same rules as for Fight Club.) I don't want to hear anyone asking "Is schmooo lossless?" laugh.gif

[/brief sarcasm]

Edit: Fixed formatting mistakes

This post has been edited by ScorLibran: Aug 2 2003, 07:32
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deej_1977
post Aug 2 2003, 07:47
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I have a similar question I am just dying to ask: is 256kbps MP3 CD quality? wink.gif

(for those of you who have never been on the - allas deceased - r3mix forums: please don't answer this question, makes people go wacko.gif)

Although I do wonder wether the current 16-bit CD format doesn't limit a bit the dynamic range of the music, compared to the good old LP?

This is a very subjective impression, let me explain: my dad has an old original and well-kept LP lying around from CCR, Willy And The Poor Boys. I happened to pick it up on CD a couple of days ago and compared the two on the same amp and speakers at my dad's (I don't own a turntable). It's probably just me or the remastering quality but the LP sounds "warmer, fuller" then the CD, as if the CCR boys can really play all out, pedal to the metal.

It's just an impression I guess. And BTW: yes I can ABX it because the LP has little cracks and pops from time to time smile.gif.

This post has been edited by deej_1977: Aug 2 2003, 08:03


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Pio2001
post Aug 2 2003, 11:43
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QUOTE (deej_1977 @ Aug 2 2003, 09:47 AM)
Although I do wonder wether the current 16-bit CD format doesn't limit a bit the dynamic range of the music, compared to the good old LP?

No, an LP has a dynamic range of about 13 bits.

QUOTE (ScorLibran @ Aug 2 2003, 04:28 AM)
"lossless" is a sacred word with an absolute definition in the realm of recorded audio.  One that effectively prevents it from ever correctly being used to describe recorded audio.


Actually, lossless is a word defined in the digital domain. Any word or physical theory is valid under a given field of application, under a given context.
For example, all the arguments used so far here to explain that music recording can't be lossless assume that sound is a continuous real function of time and space that for each position of space and time (x, y, z, t) defines a real number that describes the pressure of the air. But is this a valid assumption ? Yes, under most, if not all practical circumstances. But it is still a simplified model. A more accurate description would be that sound is a flux of phonons subject quantum mechanics laws.

So asking if something is lossy or nor doesn't make sense without specifying lossy under what circumstances.

Lossless for human ear ? That's rather called "perceptually transparent".
Lossless for a digital file ? That means that it allows to reconstruct the original file bit for bit.
Lossless for live recording ? As long as bit depht and sample rate are above the mics, amplis and speaker noise and frequency limits, a digital recording can be.
Lossless for musical performance ? That requires three dimentional continuous analysis (x, y, z, t), but can be achieved in theory as long as the resolution is higher than the air's acoustic properties.
Lossless for physical air pressure ? As long as we record enough quantum informations about phonons so as to have more info that is necessary to define the concept of "pressure", that has only a macroscoping meaning.
Lossless for the phonons's flux ? That might be achieved under forthcoming supesymetric theories. This may or may not cover the time-space concept at Plank's limits, and virtual particles defining vacuum's energy.

Whether this can be continued endlessly is a question that divides specialists (physicists and philosophers). Buddhists philosophers have strong arguments showing that this is endless, and thus that lossless is impossible. That's also the belief of many phisicists, but not all. Stephen Hawkins for exemple thinks that a final physical theory exists and can be found. Under this theory, lossless may or may not be possible. Buddhists philosophers ask "if this theory exists, Why does it exists and not another one ?". Answer this question, and the theory is not complete since it has a cause outside itself, in another theory. Don't answer it, and the theory has no proof or background.
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KikeG
post Aug 2 2003, 14:06
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Under that strict definition of "lossless", no real-world recording system can be lossless, be it digital or analog, now or ever, since it's impossible both to capture and store the variations of pressure with infinite detail.

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Lego
post Aug 2 2003, 15:13
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QUOTE (rjamorim @ Jul 31 2003, 11:11 PM)
What a worthy and useful thread. >_<

@rjamorim

Yep, i agree to you

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Pio2001
post Aug 2 2003, 16:03
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QUOTE (Lego @ Aug 2 2003, 05:13 PM)
Yep, i agree to you

Lego, F1Sushi, What do you want to tell with this ?

That you are not interested in this thread ? Then why don't you go and post the exact same thing in EVERY thread that didn't provide some news ?

In one word, your posts were certainly the most useless of the whole thread.

However, I'll take you point of view into account and move this into the off-topic section.
This way, there will be no point anymore in saying that "this thread is unuseful".
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F1Sushi
post Aug 2 2003, 22:32
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Thanks for moving this thread elsewhere...and my apologies - my sarcasm occasionally gets the best of me.
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ScorLibran
post Aug 4 2003, 06:03
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QUOTE (Pio2001 @ Aug 2 2003, 08:43 AM)
Actually, lossless is a word defined in the digital domain. Any word or physical theory is valid under a given field of application, under a given context.
For example, all the arguments used so far here to explain that music recording can't be lossless assume that sound is a continuous real function of time and space that for each position of space and time (x, y, z, t) defines a real number that describes the pressure of the air. But is this a valid assumption ? Yes, under most, if not all practical circumstances. But it is still a simplified model. A more accurate description would be that sound is a flux of phonons subject quantum mechanics laws.

And if sound is a continuous real function of time and space, then that would imply that it would have an infinite number of real numbers to describe all positions, right? That would seem to lend toward the theory that recording could never be lossless. And in your second description, even if there were not an infinite amount of data, it would still seem to be too much to reasonably capture in a lossless way. Something along the lines of one minute of audio becoming a terabyte of recorded data, for example (or some other extreme amount).

QUOTE (Pio2001 @ Aug 2 2003, 08:43 AM)
So asking if something is lossy or nor doesn't make sense without specifying lossy under what circumstances.

-a. Lossless for human ear ? That's rather called "perceptually transparent".
Lossless for a digital file ? That means that it allows to reconstruct the original file bit for bit.
-b.Lossless for live recording ? As long as bit depht and sample rate are above the mics, amplis and speaker noise and frequency limits, a digital recording can be.
-c.Lossless for musical performance ? That requires three dimentional continuous analysis (x, y, z, t), but can be achieved in theory as long as the resolution is higher than the air's acoustic properties.
-d.Lossless for physical air pressure ? As long as we record enough quantum informations about phonons so as to have more info that is necessary to define the concept of "pressure", that has only a macroscoping meaning.
-e.Lossless for the phonons's flux ? That might be achieved under forthcoming supesymetric theories. This may or may not cover the time-space concept at Plank's limits, and virtual particles defining vacuum's energy.

I agree that it's important to define the scope of the term "lossless". I have taken the position that it is an absolute term rather than a subjective one. I took the liberty of indexing your examples above. -a. is subjective and hardly (or not) quantifiable, so lossless wouldn't apply. -b. is quantifiable and absolute, so I agree, lossless can easily be achieved. -c. is the tough one...is it an infinite function? If so, then lossless capture would be impossible there as well, regardless of how high resolution would because you're dealing with a continuous wave (or maybe the concept of capturing with continuity is just beyond my ability to understand/believe?) -d. would result in a finite quantity, unless I'm mistaken, so I agree that lossless would be possible by that definition. -e. sounds likely not possible to be lossless at this time, but I agree that extending and proving current scientific theories might make it possible.

To oversimplify things for a minute, this entire debate makes me think of what it would have been like in, say, 1940, when the speed of sound was the golden ring for aviators. So many people said, and even tried to prove theoretically, that traveling at or beyond the speed of sound was a scientific impossibility. Then 1947 came.

QUOTE (Pio2001 @ Aug 2 2003, 08:43 AM)
Whether this can be continued endlessly is a question that divides specialists (physicists and philosophers). Buddhists philosophers have strong arguments showing that this is endless, and thus that lossless is impossible. That's also the belief of many phisicists, but not all. Stephen Hawkins for exemple thinks that a final physical theory exists and can be found. Under this theory, lossless may or may not be possible. Buddhists philosophers ask "if this theory exists, Why does it exists and not another one ?". Answer this question, and the theory is not complete since it has a cause outside itself, in another theory. Don't answer it, and the theory has no proof or background.

Interesting that this can be analyzed equally with religion, philosophy and science. smile.gif

"How did the universe begin?"

"Will we ever be able to go faster than the speed of light?"

"Will lossless recording of live audio ever be possible?"

tongue.gif

I guess my final thought is that I believe lossless recording can be possible, but it will take more science than we've currently mastered. And, for that matter, probably more philosophy and religion as well. Maybe in five years. Or ten. Or a hundred. Or maybe in three months...who knows?


Edit: Fixed formatting mistakes.

This post has been edited by ScorLibran: Aug 4 2003, 06:11
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