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That depends on what you're listening to. For all my progressive/power metal, 128 just sounds terrible and empty. I'm not very well versed in the terminology, s

That depends on what you're listening to. For all my progressive/power metal, 128 just sounds terrible and empty. I'm not very well versed in the terminology, so I don't know how better to describe it. On the contrary, 320 sounds full. My two cents.

cageface 15y ago
People make a lot of those kinds of qualitative statements about sound quality, but when they actually do a rigorous A/B test they usually can't tell the difference. I've done quite a bit of A/B testing on metal at ~128 kbits and it's very difficult to spot differences on most tracks. Modern lossy audio encoders are very, very good.
- Shenglong 15y ago
  Maybe it's a technology difference, but that's the general feel I have across most tracks I've listened to. I'm not A/B testing specifically, but I was complaining about 128 kbit tracks and asking why they sounded empty, even before I knew about bit rates. Systematic Chaos, on 320 for example, sounds amazing. I'll do some specific testing before I say anything else. :)
  - cageface 15y ago
    Audio perception is highly subject to placeo effect. If you're curious the community at http://www.hydrogenaudio.org/forums/ http://www.hydrogenaudio.org/forums/ has worked very hard to make this a more rigorous scientific process. It's pretty remarkable how good modern lossy encoders are really. I consider it one of the more impressive feats of software engineering of the last decade.
- lloeki 15y ago
  Most tracks is not enough. I don't want to lose time fiddling with optimal quality/size ratio per song. 256kbps AAC, clickety click, fits anything and makes a nice, small rip for zero overhead.
- shazow 15y ago
  Using decent in-ear headphones (I like the Etymotic HF2), listening to Justice, I can definitely without a doubt tell the difference between 128 kbit and +256 kbit. Or more specifically, 128 kbit and lower for specific music makes me feel nauseous. I'm guessing this type of music simply doesn't compress as well as say... Red Hot Chili Peppers. I'm not performing a rigorous A/B test, and I can believe that I would fail said A/B test given other conditions (other speakers, other music, etc). I would love for this to be true for all conditions and save all that storage space. Unfortunately, in my personal real-life conditions, better quality does make for a better listening experience.
  - baddox 15y ago
    Are you doing the encoding and performing A/B tests yourself? There are all kinds of things that can hurt audio fidelity a lot worse than bitrate. Some MP3's are poorly encoded by some crappy shareware application. Some are transcoded from an already-lossy source. Some productions will compress better than others (supposedly, some producers actually mix and master with inevitable compression in mind).
    - shazow 15y ago
      My original source was pirated music at 128kbits. Since then, I bought it and have the 320kbit version which immediately sounded incredibly better. Occasionally I'll hear it on 128kibts or 192kbits on Pandora and such, and the difference is very noticeable to me. My data is purely anecdotal but I feel strongly about it and would be willing to put money where my mouth is if someone wants to call me on it.
lloeki 15y ago
Harmonics probably get cut off early. At 128Kbps (Even VBR) I have numerous songs which end up being simply distorted and blocky. 160kbps MP3 is a minimum for those. There's simply too much information to pack in certain areas.
- cageface 15y ago
  Most mp3 encoders do lowpass filter at those bitrates, but only at frequencies outside the hearing range of most people.
  - mattgreenrocks 15y ago
    > only at frequencies outside the hearing range of most people. That is the idea, but the reality is that past a certain bitrate, songs begin sounding weak/metallic. That bitrate is dependent upon the listener, the equipment, the song, and the codec. I cannot give you any nice, objective numbers here since sound quality is heavily subjective. But you cannot discount subjective experience here simply because a study found that x% of the general population cannot discern the difference between 128kbps MP3s and 320kbps MP3s. My own experience is that many songs suffer with 128kbps MP3s, particularly classical. I've used at least 192kbps MP3s since I started storing my music collection on a computer. Also consider the fact that if bitrate was irrelevant, why are the content providers tending toward higher bitrates? We can safely assume they'd prefer to act in their own interests and keep bandwidth as low as possible.
    - cageface 15y ago
      Go to http://www.hydrogenaudio.org/forums/ http://www.hydrogenaudio.org/forums/ and you can find all the nice objective numbers you want. The reality is that they now do listening tests at <96kbits because the encoders are too good above that threshold. Subjective is no more useful here than it is any other quantifiable, scientific application. Providers push higher bitrates because customers think they're better and demand them.
    - ugh 15y ago
      Did you do a well controlled blind test is? That’s, I guess, the relevant question. I don’t think you can trust your ears if you know what you are listening to. I do actually recommend doing just that. It doesn’t matter who can and cannot hear what, what matters is whether you can hear the difference in a blind test. I did just that before I started buying compressed music. (I didn’t try 128kbps MP3s. I consequently don’t know whether I can hear the difference. I tried 256kbps AAC files – those were the ones I was planning on buying – and I most certainly couldn’t hear the difference.) MP3 certainly is limited, it even has some problems that are inherent to it, not even a higher bitrate can fix those. Short, sharp sounds (think castanets), for example, are a problem. Because of the way human hearing works, loud sounds mask quiet sounds. MP3 (and other lossy compression algorithms) use this mask to hide noise (the noise that results from compressing the audio). In order to be able to do that the algorithm has to figure out where the mask is and there is, of course, a time dimension to that mask. MP3 can’t have arbitrarily short masks, it is consequently possible that the noise that’s supposed to be hidden under a loud sound spills over to sections where everything is actually quiet. This happens when there is a short loud sound followed by silence. You know, castanets. No high bitrate can solve that problem (it can only reduce the overall noise that has to be hidden) but newer compression algorithms (like, for example, AAC) are more flexible with their masks and don’t necessarily have the same problem.
shrikant 15y ago
To my [untrained] ears, the difference between lossless and lossy compression on Ravel's Bolero is remarkably stark. The delta between 128/160 and 320 is not as clear as above, but still noticeable. In sum, I suppose this would depend on the nature of the music being listened to.
rmc 15y ago
Do you notice this difference on a music track if you don't know the bitrate? If you know that something is 128, then many people think it's worse.

cageface 15y ago

People make a lot of those kinds of qualitative statements about sound quality, but when they actually do a rigorous A/B test they usually can't tell the difference. I've done quite a bit of A/B testing on metal at ~128 kbits and it's very difficult to spot differences on most tracks. Modern lossy audio encoders are very, very good.

Shenglong 15y ago
Maybe it's a technology difference, but that's the general feel I have across most tracks I've listened to. I'm not A/B testing specifically, but I was complaining about 128 kbit tracks and asking why they sounded empty, even before I knew about bit rates. Systematic Chaos, on 320 for example, sounds amazing. I'll do some specific testing before I say anything else. :)
- cageface 15y ago
  Audio perception is highly subject to placeo effect. If you're curious the community at http://www.hydrogenaudio.org/forums/ http://www.hydrogenaudio.org/forums/ has worked very hard to make this a more rigorous scientific process. It's pretty remarkable how good modern lossy encoders are really. I consider it one of the more impressive feats of software engineering of the last decade.
lloeki 15y ago
Most tracks is not enough. I don't want to lose time fiddling with optimal quality/size ratio per song. 256kbps AAC, clickety click, fits anything and makes a nice, small rip for zero overhead.
shazow 15y ago
Using decent in-ear headphones (I like the Etymotic HF2), listening to Justice, I can definitely without a doubt tell the difference between 128 kbit and +256 kbit. Or more specifically, 128 kbit and lower for specific music makes me feel nauseous. I'm guessing this type of music simply doesn't compress as well as say... Red Hot Chili Peppers. I'm not performing a rigorous A/B test, and I can believe that I would fail said A/B test given other conditions (other speakers, other music, etc). I would love for this to be true for all conditions and save all that storage space. Unfortunately, in my personal real-life conditions, better quality does make for a better listening experience.
- baddox 15y ago
  Are you doing the encoding and performing A/B tests yourself? There are all kinds of things that can hurt audio fidelity a lot worse than bitrate. Some MP3's are poorly encoded by some crappy shareware application. Some are transcoded from an already-lossy source. Some productions will compress better than others (supposedly, some producers actually mix and master with inevitable compression in mind).
  - shazow 15y ago
    My original source was pirated music at 128kbits. Since then, I bought it and have the 320kbit version which immediately sounded incredibly better. Occasionally I'll hear it on 128kibts or 192kbits on Pandora and such, and the difference is very noticeable to me. My data is purely anecdotal but I feel strongly about it and would be willing to put money where my mouth is if someone wants to call me on it.

lloeki 15y ago

Harmonics probably get cut off early. At 128Kbps (Even VBR) I have numerous songs which end up being simply distorted and blocky. 160kbps MP3 is a minimum for those. There's simply too much information to pack in certain areas.

cageface 15y ago
Most mp3 encoders do lowpass filter at those bitrates, but only at frequencies outside the hearing range of most people.
- mattgreenrocks 15y ago
  > only at frequencies outside the hearing range of most people. That is the idea, but the reality is that past a certain bitrate, songs begin sounding weak/metallic. That bitrate is dependent upon the listener, the equipment, the song, and the codec. I cannot give you any nice, objective numbers here since sound quality is heavily subjective. But you cannot discount subjective experience here simply because a study found that x% of the general population cannot discern the difference between 128kbps MP3s and 320kbps MP3s. My own experience is that many songs suffer with 128kbps MP3s, particularly classical. I've used at least 192kbps MP3s since I started storing my music collection on a computer. Also consider the fact that if bitrate was irrelevant, why are the content providers tending toward higher bitrates? We can safely assume they'd prefer to act in their own interests and keep bandwidth as low as possible.
  - cageface 15y ago
    Go to http://www.hydrogenaudio.org/forums/ http://www.hydrogenaudio.org/forums/ and you can find all the nice objective numbers you want. The reality is that they now do listening tests at <96kbits because the encoders are too good above that threshold. Subjective is no more useful here than it is any other quantifiable, scientific application. Providers push higher bitrates because customers think they're better and demand them.
  - ugh 15y ago
    Did you do a well controlled blind test is? That’s, I guess, the relevant question. I don’t think you can trust your ears if you know what you are listening to. I do actually recommend doing just that. It doesn’t matter who can and cannot hear what, what matters is whether you can hear the difference in a blind test. I did just that before I started buying compressed music. (I didn’t try 128kbps MP3s. I consequently don’t know whether I can hear the difference. I tried 256kbps AAC files – those were the ones I was planning on buying – and I most certainly couldn’t hear the difference.) MP3 certainly is limited, it even has some problems that are inherent to it, not even a higher bitrate can fix those. Short, sharp sounds (think castanets), for example, are a problem. Because of the way human hearing works, loud sounds mask quiet sounds. MP3 (and other lossy compression algorithms) use this mask to hide noise (the noise that results from compressing the audio). In order to be able to do that the algorithm has to figure out where the mask is and there is, of course, a time dimension to that mask. MP3 can’t have arbitrarily short masks, it is consequently possible that the noise that’s supposed to be hidden under a loud sound spills over to sections where everything is actually quiet. This happens when there is a short loud sound followed by silence. You know, castanets. No high bitrate can solve that problem (it can only reduce the overall noise that has to be hidden) but newer compression algorithms (like, for example, AAC) are more flexible with their masks and don’t necessarily have the same problem.

shrikant 15y ago

To my [untrained] ears, the difference between lossless and lossy compression on Ravel's Bolero is remarkably stark. The delta between 128/160 and 320 is not as clear as above, but still noticeable. In sum, I suppose this would depend on the nature of the music being listened to.

rmc 15y ago

Do you notice this difference on a music track if you don't know the bitrate? If you know that something is 128, then many people think it's worse.