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Double blind test 128Kbps vs lossless? I'll be amazed if you can tell much difference - Page 10

post #136 of 257

Yep I'm sure the difference is there, I only needed to listen to about 30 secs of each file to hear it. The main difference is the mp3 file lacks a certain airiness and the treble sounds cut off instead of smooth and ending on a light airy note. I did the test using $50 IEM's plugged straight into my Toshiba laptop. So If I can hear the difference using this lackluster setup imagine what it would sound like on my full blown rig :S

post #137 of 257

guess that proves I'm suffering from hearing loss already at my age whoopie doodle doos

post #138 of 257

I'm sure I'll be taken as your typical "audiophile" crackpot because of this, but I'm speaking from my interest and education in neuroscience more so than my interest in audio. I find myself falling on the side of skepticism when it comes to most of the more controversial claims in audio, especially when people claim a difference when no such difference is measurable by more reliable tools than the human ear and nervous system. But in the case of lossy and lossless audio, here we have very measurable differences, and of course then the question then becomes whether or not the human ear and nervous system are capable of perceiving those differences. But we run into a very large obstacle in the ABX testing in that being able to perceive a specific stimulus and being able to translate it into the realm of conscious thought are two very, very different things. In which case, one might have great difficulty being able to say which is which in the context of a test, but if they were to then do all of their listening in a lossy format, they might find that they have just a little more trouble getting into their music. They might not be able to say that they "hear" anything wrong, because the differences wouldn't be significant on a conscious level. But all the same, stimuli which we are not able to bring to conscious attention can have a profound effect on how we experience things. On the other hand, if I were a betting man, I'd have to think that in such a scenario, one might perform better on ABX testing than they would guessing randomly, even if they felt that they truly were guessing. But that's really conjecture, and I wouldn't put much stock in it.

 

And mind you, I'm not saying that this *is* the case, but it is a very real possibility that's been bothering me. I'm also not entirely sure how such a concern could be addressed in an experiment without some pretty pricey equipment (as much as we may love pricey equipment here), and it's just not practical. So... take it as you will, I suppose.

post #139 of 257
Quote:
Originally Posted by T.R.A.N.C.E. View Post

Yep I'm sure the difference is there, I only needed to listen to about 30 secs of each file to hear it. The main difference is the mp3 file lacks a certain airiness and the treble sounds cut off instead of smooth and ending on a light airy note. I did the test using $50 IEM's plugged straight into my Toshiba laptop. So If I can hear the difference using this lackluster setup imagine what it would sound like on my full blown rig :S


What I'm not sure you get is that no matter how sure you are, assuredness is no proof. I bet those differences are real, but we can't just take your word for it. If you want to prove you're right, ABX. If not, that's fine.

 

But since you only listened to one file and gave only one result, even if file 2 proves to be the lossless one, that's not proof that you personally were right. Only that, as a whole, the people who participated were able to beat chance.

post #140 of 257

I don't need to prove anything to anyone, I only took the test to prove to myself that I could tell the difference between lossy and lossless. All I know is that I could definitely hear the difference that I've always heard between lossy and lossless. So I'm quite satisfied.


This thread is essentially pointless, everyone has different hearing. The persons test results are only use full to himself, not others. If I can definitely hear the difference it means that I should use FLAC as I will get the most enjoyment from my audio, for people that can't hear it then they should use MP3 and save some space, make sense? Jeez.


Edited by T.R.A.N.C.E. - 7/14/10 at 9:30pm
post #141 of 257
Quote:
Originally Posted by T.R.A.N.C.E. View Post

 


This thread is essentially pointless, everyone has different hearing.


I could not agree more! For it to be of any real use a panel of people from all age groups who have had their hearing measured by a proffesional and then take the test. Only then could we get a more accurate picture.

All this ABX nonsense listening to an alien track makes me laugh.

 

Surely perception is more accurate when we listen to tracks we know well, I think that is a better test in absence of this test as  for me reading folks who can hear whatever they can hear with tracks that are well known to them is of far more use to me than a bunch of folks listning possibly to a track they have never heard of before. What if some of those people never listen to classical, they simply would have no idea about the subtle nuances in that music.

 

I must admit I dipped my toe back into this thread and will pull it right back out now. It seems a few folks have an adgenda on it being done in a certain way and then arguing that anyone who did it different is a liar!!

post #142 of 257

yeah, I'm wit you ^, pointless. I have forgotten why I am reading this thread.

 

reminder to self: delete subscription

post #143 of 257
Quote:
Originally Posted by Spelaeus View Post

 But we run into a very large obstacle in the ABX testing in that being able to perceive a specific stimulus and being able to translate it into the realm of conscious thought are two very, very different things. In which case, one might have great difficulty being able to say which is which in the context of a test, but if they were to then do all of their listening in a lossy format, they might find that they have just a little more trouble getting into their music. They might not be able to say that they "hear" anything wrong, because the differences wouldn't be significant on a conscious level. But all the same, stimuli which we are not able to bring to conscious attention can have a profound effect on how we experience things. .



That is an interesting question. Tom Nousaine attempted to address the question of if DBT was a problem compared to long term listening. In hs experiment he gave black boxes to audiophiles which they added to their systems, some were straight pass-thrus others injected 2.5% distortion. Of the black box testers the hit rate was exactly 50% i.e random chance. When the test was changed to a DBT with instant swapping the lisiteners were all able to reliably detect the difference, the swictchable DBT was shown in this case to be far more sensitive than long term listening.

post #144 of 257
Quote:
Originally Posted by T.R.A.N.C.E. View Post

I don't need to prove anything to anyone, I only took the test to prove to myself that I could tell the difference between lossy and lossless. All I know is that I could definitely hear the difference that I've always heard between lossy and lossless. So I'm quite satisfied.


This thread is essentially pointless, everyone has different hearing. The persons test results are only use full to himself, not others. If I can definitely hear the difference it means that I should use FLAC as I will get the most enjoyment from my audio, for people that can't hear it then they should use MP3 and save some space, make sense? Jeez.


If you can definitely hear a difference why not do the DBT it really does not take very long, maybe 20 - 30 minutes and then you can be as smug as you like with justification. Some can hear the difference in DBT some cannot, I personally cannot with this sample, though I can DBT other samples, shrug, but the certainty you have is misplaced until you have rigorously tested it yourself.  In Masters and Clark's "Do all amplifiers sound the same" tests the listeners frequently had absolute rock-solid certainty when they knew that A and B were different and they knew which one they were listening to. Once that knowledge was taken away they lost the ability to detect differences.

 

Guessing correctly once or twice is really not great evidence, especially when you already know that A and B are different , getting it right 15/20 times when you have to explicitly compare A and B to an X provides much better credibility.

post #145 of 257



 

Quote:
Originally Posted by ianmedium View Post

 

 

Surely perception is more accurate when we listen to tracks we know well, I think that is a better test in absence of this test as  for me reading folks who can hear whatever they can hear with tracks that are well known to them is of far more use to me than a bunch of folks listning possibly to a track they have never heard of before. What if some of those people never listen to classical, they simply would have no idea about the subtle nuances in that music.

 


Actually there is no evidence to support that assertion, that is just audiophile folk-wisdom not supported by any published data afaik, it is one of those things that seems intuitively right, but the evidence does not support this, for instance hearing distortion in pure tones, something we rarely listen to is far easier than hearing it in music that we are familiar with, similarly hearing the difference between two playback systems is easier when using simple music specifically single voice or single instrument samples, once you have a complex signal the small differences are much harder to pick up (Blech and Yang 2005, Meyer and Moran 2007, Benjamin and Gannon 1998). Given that our audio memory is so poor this is perhaps not surpirsing. So it is not familiarity but the underlying structure of the music that makes most difference, in general.

post #146 of 257

My experience certainly supports the added sensitivity to familiar music.  In blind tests with my own mixes, I can pick out the difference between 16 and 24 bit files.  And that's a much more subtle difference than what this post is about.  After hearing the same mix over and over for hundreds of hours, tiny changes stick out.  But when listening to something for the first time, I'm happy to have mid quality MP3s.

 

When I get home, I'm curious to download the two samples posted here. 

post #147 of 257

It would be good to have a file with 3 lossless and one lossy ,and vice versa - rather than a 50/50 chance.

Then play file one,` which is the lossless track A,B,C or D?` and vice versa for lossy.

post #148 of 257


 

Quote:
Originally Posted by tmars78 View Post




Makes sense to me. And I am trying to ABX 96K and 128K as we speak, and its suffice to say, I can't pick them apart. I am not practically guessing, I am guessing. 


OK, so I went ahead and ripped a few tunes using iTunes and did some testing with The Offspring's "I Want You Bad." I did a double-blind test using Foobar2000 and the ABX plug-in on a 96k file and a 128k file. This was on a Dell Mini 9 netbook using a pair of Sennheiser HD-238 phones. The good news for me was that I was able to distinguish between the two tracks 100% of the time. I did 5 passes and scored 5/5 (3.1% probability of lucky guesses).

 

The bad news for me is that, though I could detect sonic differences between the two tracks, I couldn't tell by listening which of the two was the higher bitrate track. One sounded a bit airier and thinner and the other sounded a bit darker and duller. But I had to really, really pay attention to pick out the differences.

 

The long and the short of it is: I was wrong in thinking I could pick out a 96k track without a frame of reference (a higher bitrate track to compare it to). 96K really is a lot better sounding than I thought.

 

I went ahead and ripped a track in 64k MP3 and 192k AAC (which is what I've got on my iPod). Here, of course, the difference is night and day. On the 64K track the cymbals in the intro simply disappeared. Distinguishing between the 128k MP3 and the 192k AAC was another matter altogether. I didn't run any actual tests, but based upon a quick listen I doubt I'd do much better than chance.

 

So I have to assume that the poorly encoded Led Zeppelin CD I had was encoded at 64K and not 96k.


Edited by dsf3g - 7/16/10 at 1:41am
post #149 of 257

^  

Thx for coming back w/ your experiences.  

post #150 of 257

Highly detailed music (Classical, Shpongle etc) benefit massivley from lossless in my opinion.

 

I could never listen to music I love in mp3 format unless I was desperate and had rubbish headphones and no amp.

Its because of the iPod generation that Hi-Fi's in stores are rubbish and modern music is so poorly produced. Becuase they can get away with it an no one can tell on there iPod headphones/MP3s or low quality modern HiFi MIDI sytems. LOL again in my humble opinion.

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