Sound quality between CD and downloaded song

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  • KodazKodaz Posts: 1,018
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    Landis wrote: »
    We've done the double blind test. The listener was unable to identify the wav [etc]
    Landis wrote: »
    Now - Let's remove the part that you invented based on the snippet of dialogue from the imaginary double-blind test.
    What's left?

    As I said, that was my attempt at interpreting what you meant, accurate or not.

    Note the "etc" in square brackets at the end to indicate editing for brevity. However, I was still referring to the whole paragraph (else I'd have left the [etc] out). Maybe that should have been clearer. Here's what I was referring to in full:-
    Landis wrote: »
    We've done the double blind test. The listener was unable to identify the wav files from the 320kbps files. This is clear proof that the impact that music has on humans is not impacted - in any way - by the bit rate. Let's pack up and go home!

    "But....he clearly heard the audio artifacts when we started out with a bit rate of......"

    Nope. Not Listening! la la la lal la la!


    We've done the double blind test with the oranges. Kodaz cannot discern any difference whatsoever in taste or texture. Lets put him on the Faux Orange Diet!
    Apologise to Kodaz for secretly swapping the oranges - He needs to understand that all this was "for his own good".
  • BrokenArrowBrokenArrow Posts: 21,665
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    Lets not forget that CD wave files are not perfect in themselves as they use 16 bit samples which causes quantisation distortion (pretty small, I admit at around -96dB) but still it can be screwed up if the mastering is done wrong.

    I have several CD's which have really bad quality distortion because they have'nt levelled them properly.
  • scruffpotscruffpot Posts: 4,570
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    I was involved with a university running a test on CD and MP3. My score for 30 CD's and 30 MP3 was 85% correct, being able to tell the difference.

    I personally prefer CD they sound a lot better compared to MP3 (dependent on their bite rate of course) on my set up.

    However there is a host of reasons why I prefer CD, Vinyl and tapes, its not to do entirely over quality, but over actually having something in my hands, the box the artwork, trying to take off the annoying piece of plastic wrap.

    In my personal opinion, music these days is generally a throw away commodity, as it is so easy to go online down load a track and or delete it, compared to going out buying a CD going home having it there and playing it.. there is a physical attachment, you have it actually there in front of you, instead of in 1's and 0's on a hard drive. This maybe why we are plagued with so much crap music and that artists are just as disposable as their songs. The removal of the physical removes the physical attachment as you don't actually see the CD you just see the device that holds the MP3.

    Don't get me wrong the MP3 is a fantastic invention and has revolutionized music and the industry, but the way its all going digital, marketing and the download stores I feel that the soul of music is slowly dripping away.

    However there is more and more music being produced and technology is playing a huge part in it, but with the invention of electronic instruments and other instruments and the ease it is to make music does mean that there is more and more crap being created. Anyone can use a music program and a synth but doesn't mean your going to make anything good. Same as the rise in digital photography, anyone can own a digital camera, - as the internet is awash with pictures and set up studios but if you don't understand the principles behind it, how to use your equipment, how to take photos etc then your just going to make rubbish.

    So much production and music work gets lost when groups just downsample their music to be released only on download. sad really


    grumble grumble pipe and slippers.

    However what I hope is since the sort of death of HMV and other big chains is hopefully the rise of small independent music shops on the high street.

    what would be nice would be if Noisia had released all of their Devil May Cry album on CD not just part CD and 320kbps
  • gemma-the-huskygemma-the-husky Posts: 18,116
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    never mind CD

    you can hear a difference with vinyl.
  • 2Bdecided2Bdecided Posts: 4,416
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    Landis wrote: »
    And I did not come onto the thread to promote my own test or any other test. I came onto the thread to comment on the introduction of double blind tests (to the discussion) by amother forum member. :)
    To me, this suggests you're one of those people who has to try to disprove the relevance of double-blind testing, because some of the differences you claim to hear go away when you don't know what you're listening to.

    Scientists say this is the placebo effect. i.e. it's all in your head (though real enough to you) and not due to any characteristic of the sound itself. Audiofools claim some kind of magic "beyond science", and that the differences are real and audible. Some of them are mad enough to claim "night and day" differences, that then magically disappear in blind testing. It makes no sense, but there's a (dying) industry built on it.

    Luckily medicine sticks without double-blind testing - you may feel music is more important, but in life-or-death treatment, double-blind testing wins. Only Quacks reject it.


    Any emotional response to the music happens in your brain from the input of your senses and experience/memory. The real magic is that the (highly complex) transduction process in human ears is fairly well understood; the information that doesn't get passed from the ear to the brain does not need to be included in the audio signal. It can have no effect on emotion because the brain does not know about it - it's not even conscious vs unconscious - the information is not available at any level.


    It's fun to argue "ah yes, but does it feel the same", and suggest that there must be unconsciously heard differences. However, this just becomes a Russell's teapot argument. It's also laughable to anyone who has ever (emotionally!) enjoyed music played on AM radio. Music could be with a 5kHz bandwidth and interference, but according to the anti-mp3 argument, completely inaudible changes to the signal might ruin the "mood".

    Cheers,
    David.

    P.S. Note my previous post in this thread. Even 320kbps is not always transparent. The model of human hearing in audio codecs isn't perfect (though far better than mp3 is available). Considering it was designed to run faster than real time on 1990s hardware, it's not doing bad. I don't see the rest of what's in a human head being simulated to any comparable degree of accuracy any time soon ;)
  • jackthomjackthom Posts: 6,627
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    never mind CD

    you can hear a difference with vinyl.

    I could never afford a turntable/arm/cartridge combination that was anywhere near good enough to avoid annoying levels of rumble and tracking distortion. Not to mention the fairly rapid deterioration of the playing surface and the resulting noise from the discs themselves.

    There's definitely no going back to vinyl for me.
  • Nigel GoodwinNigel Goodwin Posts: 58,453
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    jackthom wrote: »
    I could never afford a turntable/arm/cartridge combination that was anywhere near good enough to avoid annoying levels of rumble and tracking distortion. Not to mention the fairly rapid deterioration of the playing surface and the resulting noise from the discs themselves.

    There's definitely no going back to vinyl for me.

    Nope, I'm with you there :D
  • flagpoleflagpole Posts: 44,641
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    I did this http://nigelcoldwell.co.uk/audio/

    a while back to compare the quality of different codecs and bitrates.

    there is a blind test too. if you dare.
  • LandisLandis Posts: 14,855
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    2Bdecided wrote: »
    To me, this suggests you're one of those people

    David/2Bdecided

    I enjoyed reading your post.

    I have not dismissed the possibility that, to all intents and purposes, high bit-rate MP3 files/wav files are "the same" ie that they provide the same experience. We are simply talking about it. But you seem to have dismissed the possibility that they are not the same, and do not provide the same experience (Audiofools etc...). Am I being fair to you? How do we know what insight future studies will bring us?
    I don't think I have ever met an Audiophile and if someone introduced themselves to me as such I am not sure that I would able to suppress laughter.
    The dullest exchange in the world is I can hear it/Well take a test then/ I don't need a test/You don't trust your ears/But I can hear it/ Well take a test then......!
    But when the Audiophile/fool says: "You are right. Under the test conditions I am doing no more than guessing" - That's a starting point for an interesting discussion.
  • Glawster2002Glawster2002 Posts: 15,211
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    2Bdecided wrote: »
    To me, this suggests you're one of those people who has to try to disprove the relevance of double-blind testing, because some of the differences you claim to hear go away when you don't know what you're listening to.

    Scientists say this is the placebo effect. i.e. it's all in your head (though real enough to you) and not due to any characteristic of the sound itself. Audiofools claim some kind of magic "beyond science", and that the differences are real and audible. Some of them are mad enough to claim "night and day" differences, that then magically disappear in blind testing. It makes no sense, but there's a (dying) industry built on it.

    But then if someone wants to spend a lot of money on a hi-fi system because that is what they enjoy why shouldn't they? :confused:
  • [Deleted User][Deleted User] Posts: 237
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    If I may add my two pence worth?

    I firmly believe that I can hear the difference between 320kbps MP3 and CD. Having said that, I'd be a little nervous to take a double-blind test in case I was proved wrong, as this would show that my hearing/music appreciation is not as good as I thought it was!

    I guess it's a bit like driving - I know I can drive pretty well, but I'd still be nervous doing another driving test in case it showed otherwise.
  • emptyboxemptybox Posts: 13,917
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    flagpole wrote: »
    I did this http://nigelcoldwell.co.uk/audio/

    a while back to compare the quality of different codecs and bitrates.

    there is a blind test too. if you dare.

    I did quite well on the blind test. Only got one file in the wrong order. (I put the 128Kb/s one higher than it should be)
    :feels quite smug: :D
  • 2Bdecided2Bdecided Posts: 4,416
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    Landis wrote: »
    But you seem to have dismissed the possibility that they are not the same, and do not provide the same experience (Audiofools etc...). Am I being fair to you?
    Not really. I have already said that there are circumstances where they are audibly different (people can pass a blind test). Also, there are uses which will reveal the lossy-ness of the signal only too well: vocal cut filters, stereo "enhancing", surround sound decoding etc will all totally break the assumption that the encoded stereo signal would be heard as-is, and let you hear the noise added by the mp3 encoder quite easily.

    I also know people who are far better at detecting minor faults than average.

    However, I also have results from people who claim, well, the things claimed in this thread: "320kbps mp3 sounds worse than CD to me" - who, in a fair test, couldn't tell a 320kbps mp3 apart from a CD if their life depended on it.

    So I spread scepticism accordingly - most people who think they can hear a difference are imagining in.

    But then if someone wants to spend a lot of money on a hi-fi system because that is what they enjoy why shouldn't they? :confused:
    Some parts of a hi-fi system, and the listening room, and the recording itself, create easily audible improvements. Even where we are talking about "differences", rather than what are certainly "improvements", someone may prefer them. Spend all you can afford. I would.

    However, it's a shame to spend (limited?) funds on things that make no difference to the sound, if your aim is to get the best sound. If you're buying it because it looks nice, or is well made, or for the same joy of ownership that you might get from a classic car or a nice watch (knowing full well that a watch at 1/100th of the price is still more than accurate enough for any practical use), then that's fine too. (In a consumer society at least - we'll leave the balancing of that against feeding starving children in Africa for another day).


    The problems come when people spend money on imagined improvements and neglect real ones. They'll soon enough get the urge to "upgrade", and sometimes make the same placebo induced mistakes ever year. This then feeds an industry that works harder on generating placebo (e.g. pretty products, expensive and hard to use tweaks), and gives up trying to deliver the best sound at a given price. You can forget enjoying the music when you get stuck on that treadmill.

    Cheers,
    David.
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