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Since its inception ten years ago, the Harbeth User Group's ambition has been to create a lasting knowledge archive. Knowledge is based on facts and observations. Knowledge is timeless. Knowledge is human independent and replicatable. However, we live in new world where thanks to social media, 'facts' have become flexible and personal. HUG operates in that real world.

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Our brains do not need High Resolution! (UNPROVEN ... READ ON)

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  • Our brains do not need High Resolution! (UNPROVEN ... READ ON)

    We don't need Hi-Res.

    We have read many times here that compressed MP3 at 256kpbs is more than enough for musical enjoyment. But for people like me, we need lossless and preferably with extended format such as SACD and others.

    Now, medical research is suggesting that our brain actually compresses the music the same way as the how the lossless format gets compressed into smaller files. It is now discovered that brain could compresses complex music to about 40% of the original information. In another word, the brain only uses a small recognizable pattern to make it enjoyable.

    Taking the examples of some lossless formats our brain could compress random noise to 86%, 60% compression for rock, techno and pop and a whopping 40% of the original information in Beethoven's 3rd Symphony. The research suggests that the act of compression of a complex music in to a simple recognizable patterns is perceived to be pleasurable

    Now, what would audiophiles say about the need for hi-res music?

    {Moderator's comment: Compress *to* or compress *by* these percentages?}

    ST
    Last edited by A.S.; 08-02-2011, 12:42 PM. Reason: added words in italics.

  • #2
    "As good as it gets" - really?

    Well, there you go then. Don't waste time building a great Hi-Fi system, just plug in your i-pod and tell yourself over and over that 'this is as good as it gets' !!!

    Comment


    • #3
      Compress "to"

      Originally posted by STHLS5 View Post
      .....

      {Moderator's comment: Compress *to* or compress *by* these percentages?}

      Well, the more complex Beethoven was compressed to 40.6% of the original size as opposed to random noise. At 2nd para of page 11 you can find

      "For example, Beethoven’s 3rd Symphony was strongly compressible to only 40.6% of
      the original file size, whereas the Techno piece “Theme from Bubbleman” by Andy
      Van, the Pop piece “I should be so Lucky” by Kylie Minogue and the Rock piece
      “White Wedding” by Billy Idol were considerably less compressible, compressing to
      68.5%, 69.5% and 57.5% of original file size respectively. Therefore, Beethoven’s 3rd
      Symphony is a better example of low Kolmogorov complexity Art [2] than Kylie
      Minogue’s “I should be so Lucky.”"

      ST

      {Moderator's comment: please re-edit you first post to clarify this point ... you were ambiguous there.}

      Comment


      • #4
        Maths or perception?

        With respect, I think STHLS5 is misreading the article, at least in terms of the portion quoted above in post #3. At pages 10-12, the author describes the apparent paradox that apparently more "complex" pieces of music (e.g. Beethoven's 3rd Symphony) can often be compressed into smaller file sizes using lossless compression algorithms than apparently "simpler" forms of music (e.g. techno, Kylie Minogue, etc). This is not a statement about the brain needing only a portion of the data to discern a pattern - it is saying something different.

        I have noticed the same phenomenon using iTunes and Apple Lossless compression. Starting from the fixed CD data rate of 1,411 kbps, I often find that pop or rock music often compresses down to file sizes of only 800 to 1,000 kpbs, while classical music (especially with simpler instrumentation, e.g. solo piano recordings) often yields much smaller file sizes. It's an interesting phenomenom, but I suspect it's more a mathematical issue than a perceptual one.

        Comment


        • #5
          Classical music and data compressability?

          Interesting post, but I don't think the thread title represents a valid conclusion! The whole point with lossless compression is that it enables one to reconstruct the original data, perfect to the last bit. In the case of general-purpose data compression (document files etc.) this is done by identifying recurring patterns in the file.

          Unfortunately I have no idea whether lossless audio codecs work in a similar way - but classical music has two characteristics that may contribute to compressibility

          1) well defined structure (e.g. sonata form and a score that every instrument plays from)
          2) very high standard of musicianship

          Comment


          • #6
            Lossless compression

            Interesting thread. Am intrigued by the concept of lossless compression, which allows reconstruction of the original data by taking advantage of repeating bit patterns. Presumably, to playback a track compressed in this way, you'd have to uncompress it on the fly. Sounds to me like the same as playing back the original. My question is, what does this have to do with resolution?
            Ben from UK. Harbeth Super HL5 owner.

            Comment


            • #7
              Asking for guidance

              Originally posted by EricW View Post
              With respect, I think STHLS5 is misreading the article, at least in terms of the portion quoted above in post #3..... This is not a statement about the brain needing only a portion of the data to discern a pattern - it is saying something different...
              Would appreciate if you could explain what the something different is all about?

              ST

              p.s. I am unsure what's to edit in the first post. Please guide me.

              Comment


              • #8
                Originally posted by hifi_dave View Post
                Well, there you go then. Don't waste time building a great Hi-Fi system, just plug in your i-pod and tell yourself over and over that 'this is as good as it gets' !!!
                Strange, you thought this post should bring us to that conclusion. Since it passed the moderation, I think you got a point.

                ST
                Last edited by STHLS5; 04-02-2011, 06:28 AM. Reason: left out the quote.

                Comment


                • #9
                  Is our hearing acuity as good as we like to believe?

                  Originally posted by STHLS5 View Post
                  Strange, you thought this post should bring us to that conclusion. Since it passed the moderation, I think you got a point.

                  ST
                  Don’t think we’re covering anything new here…

                  - Our hearing acuity and processing functions are not as good as we think it is. (deep down I think for macho reasons we display it as being, as a signal that we have inherited better genes ie. ones which got out forefathers out of danger etc.)

                  - acuity levels start to taper off at identifiable points, at least statistically

                  - “enjoyment” is too abstract or ambiguous a concept to relate with fidelity eg. Many people will be happy to dance to a boom-box or disco loudspeaker playing low resolution, low sample rate music.

                  - Some music types (but I suspect initial recording quality has more to do with it) respond better to compression (sampling and resolution) than others

                  - Nature (and the body) is by and large economical as well. It doesn’t waste resources on what is superfluous eg. ability to process hi res hi bit sound.

                  The combination of these factors makes it quite a complex issue.

                  STHL5, personally feel this is a non-issue as far as format compression (as opposed to dynamic compression) is concerned as storage is extremely affordable today.

                  Comment


                  • #10
                    High resolution = closer to 'real' music?

                    Originally posted by honmanm View Post
                    Interesting post, but I don't think the thread title represents a valid conclusion! The whole point with lossless compression is that it enables one to reconstruct the original data, perfect to the last bit.....
                    Unfortunately, the brain is not uncompressing the lossless files. It is compressing the original files to interprete them!

                    Originally posted by BAS-H View Post
                    .. My question is, what does this have to do with resolution?
                    Well, I put resolution in the heading because that's what matters in Hi-Fi today. We expected to have the highest resolution format to say we are having closer to "real" music for our enjoyment. My own experience found that to have the best musical enjoyment is not so much about resolution but the naturalness and accuracy within a narrow range of frequencies. If you remember, Peter Walker's comment about 'chromium-plated larger than life hi-fi' in Professional way of to evaluate speakers thread which he meant to say the artefacts introduced in Hi-Fi pressing. He also mentioned in that one recording company removed all frequencies above 5kHz because they do not contribute to the intelligence of the sound.

                    Is vinyl's resolution higher than SACD or even CD's? Yet, why many argue they are the best way to enjoy recorded music?

                    If we look at Hudson's research he talks about lossless compression. What happens' when lossless compression takes place? In the research papers, he is suggesting that the final interpretation of sound is in lossless compression. So the brain is only listening to the compressed version of the sound not the original.

                    ST

                    Comment


                    • #11
                      How much compression loss yields still acceptable fidelity?

                      Originally posted by STHLS5 View Post
                      Would appreciate if you could explain what the something different is all about?
                      I think I said it in my original post. The paper posits a connection between the fact that subjectively more "complex" and "beautiful" music is more compressible than "simpler" forms of music, and the way the brain arrives at that subjective assessment by decoding ("decompressing") the inherent patterns in the music. Interesting idea, in need of further proof (the cover page describes the paper as a "hypothesis", so it's not drawing any conclusions), but it is not saying what you took from it. In fact, on page 7, the author specifically states that what level of lossy (as opposed to lossless) compression yields acceptable fidelity is a "subjective" matter, which contradicts your original post.

                      Comment


                      • #12
                        Lossless Compression

                        Originally posted by EricW View Post
                        ..... In fact, on page 7, the author specifically states that what level of lossy (as opposed to lossless) compression yields acceptable fidelity is a "subjective" matter, which contradicts your original post.
                        Ok, what are you suggesting? The author clearly stated in page 5, I quote "My hypothesis builds on Schmidhuber’s insights by 1) its particular focus on music 2) the intriguing possibility that enduring musical masterpieces are “losslessly” more compressible than other “less sophisticated” pieces...". He is referring to lossless compression of the brain and not lossy compression.

                        ST

                        Comment


                        • #13
                          Originally posted by STHLS5 View Post
                          ...Taking the examples of some lossless formats[/I] our brain could compress random noise to 86%, 60% compression for rock, techno and pop and a whopping 40% of the original information in Beethoven's 3rd Symphony.

                          {Moderator's comment: Compress *to* or compress *by* these percentages?}
                          I think Mod was questioning the above line which is (to me) ambiguous. 'Compress random noise to 86%' then '60% compression for rock ....'. What exactly does that 60% comment mean? Compress to 60% (discard 40%) or does it mean discard 60% and leaving 40%. As it stands either could be applicable. Sloppy writing or reporting of what was actually discovered and all to typical of what one reads in the media.
                          Last edited by A.S.; 04-02-2011, 12:36 PM. Reason: Compression statistics ....
                          Alan A. Shaw
                          Designer, owner
                          Harbeth Audio UK

                          Comment


                          • #14
                            Comments of the Paper

                            At the top of this thread we were invited to examine the BioMed paper. I've skimmed this paper and here is what seems to lie at the core of the hypothesis:

                            For example, Beethoven’s 3rd Symphony was strongly compressible to only 40.6% of the original file size, whereas the Techno piece “Theme from Bubbleman” by Andy Van, the Pop piece “I should be so Lucky” by Kylie Minogue and the Rock piece “White Wedding” by Billy Idol were considerably less compressible, compressing to 68.5%, 69.5% and 57.5% of original file size respectively. Therefore, Beethoven’s 3rd Symphony is a better example of low Kolmogorov complexity Art [2] than Kylie Minogue’s “I should be so Lucky.”

                            But there is a further interesting observation. The relatively low compressibility of the Pop pieces is at odds – at least with my perception - that they appear on the surface to be simpler and more ordered than their Classical counterparts. Furthermore, the disparity cannot easily be attributed to the presence or absence of human vocals. Gothic Voices version of Hildegard von Bingen’s 12th century choral masterpiece Columbia aspexit compresses very strongly to 34.7%.
                            Now from my perspective, what is absent here is an appreciation of the spectral content of the classical piece differs from the pop (etc.) piece. This difference may or may not have a connection with perceived subjective musical 'complexity' as noted above. What I can see is that the entirely predictable loudness, dynamics, harmonic and melodic nature of ordered, conventional classical music versus the entirely different harmonic/melodic structure of pop music will place different demands on the compressor and hence the resulting output data will reflect that.

                            As an extreme example, often in pop music you hear a sweep tone of the type you'd generate by turning the frequency dial of an audio oscillator from low to high, or high to low. You never hear such a sound in classical music. Consequently, you would need to allocate many 'bits' in the compressor to encode this swept tone. But we know that conventional acoustic orchestral instruments produce predictable and relatively low-level harmonics which compress very well. It follows then that by careful selection of pop music that has a spectral signature similar to classical music the compressability would be similar. And I suggest that just by examining the spectral content on-screen without even listening to the music such pop music could be found.

                            I really don't think this issue is anything more than the need to adapt the compression process to the spectrum of the incoming music. Didn't we look at spectra recently in the Take5 discussion?

                            Does anyone have links to these quoted tracks and/or have the means to generate comparable (scale,. axis etc.) spectral displays?
                            Alan A. Shaw
                            Designer, owner
                            Harbeth Audio UK

                            Comment


                            • #15
                              Audio samples

                              Originally posted by A.S. View Post
                              ...Does anyone have links to these quoted tracks and/or have the means to generate comparable (scale,. axis etc.) spectral displays?
                              Hudson used the statisc of the compression ratio from www.firstpr.com.au/audiocomp/lossless/#links (see footnote 29) . You can also download the audio sample from there.

                              ST

                              Comment

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