Lossless vs 128kbps mp3 vs 320kbps mp3 blind test
Nov 30, 2015 at 1:36 AM Post #151 of 169
there is nothing wrong with trying to succeed with the proper files, the proper headphone, and taking all the time needed to train and get used to whatever it is that can be heard. maybe that will end up working great, maybe not. as an experiment I see no problem with this.
now as a representation of reality, of course it's total nonsense. what matters to me as an individual is to know if while I'm on a train or walking on the street with my IEMs that rolls off after 12khz, I would ever notice that the music is "wrong" because it's 320kbps mp3? and I believe I've answered that question for myself years ago.
wink_face.gif

 
when at home on the computer, with a relatively silent room and speakers giving me more trebles than I can hear, I fail my ABX tests. so while walking on the street it would be real misplaced pride to pretend like 320mp3 ruined my sound.
now at home again(just when I thought I was out, they pull me back in), I tend to listen to flac, because storage is not an issue so why not? but TBH I often don't pay attention and end up playing mp3 too. never killed me.
 
IMO increasing sound quality comes from kicking the butt of whoever ordered the sound engineers to mess up records for the sake of being loud. or from finding the signature that is neutral to us, or getting rid of channel imbalance and audible hiss. not so much from worrying about what happens 60 or 70db below the loudest sound of a song. or that one instrument I don't have in 99.9% of my music that's apparently messed up in mp3 at a frequency I can't hear anymore.
 
mp3 and AAC are practical codecs, and for all intended (space saving) uses, they do a fine job IMO.
 
Nov 30, 2015 at 1:00 PM Post #152 of 169
   
It does matter, because that 50% is not whether people *can* detect a difference (yes or no, 50% probability - right?), it's whether they can identify the "better" quality given they say they detect a difference. If a person isn't familiar with the music, there is no baseline to say which is better quality - which makes that 50% number quite explainable. See my previous post for reasoning. Thus a test where the listener does not know the piece as it's supposed to sound is heavily biased in my view.
 
And of course, it's BS to use musical pieces where encoding has negligible effect to "prove" bitrate doesn't matter/can't be detected. Not all music is equally affected


This is why an ABX test is better than a "which is better" style blind test. If you are given two reference samples, A and B, and then you have to match your unknown sample to one of them, you don't have to know whether A or B is the better one, and therefore you don't need to have any particular familiarity with the piece. Just listen to A and B until you're confident you know what to listen for to tell the two apart, then listen to X vs both of them and see which it matches.
 
Nov 30, 2015 at 1:41 PM Post #153 of 169
When I ABX now, I make a 96kbps mp3 to compare with a lossless version first.  I find where a specific artifact can be identified, and then I try and listen for that same artifact at the resolution that I typically use.  I just waste my time scouring a track for any differences, otherwise.
 
 I'm assuming that any problems would be amplified at a lower bit rate, but my understanding of the encoding process is vague at best.  I say this as I was able to increase the bit rate in steps and the anomaly I was hearing at 96kbps could still be identified in an ABX test up to 160kbps, at 192kbps it was not statistically valid, but the results suggested I probably was not guessing, and at 320kbps I could not hear any differences in that particular section of the song.
 
When trying to ABX 2 very good files, I just want to focus on a few seconds of a track that I know have problems at a lower bit rate.  
 
Jan 1, 2016 at 10:14 PM Post #154 of 169
My take on group 1:
 
1_A: 320 kpbs. Sounded very good, but not quite as good as 1_B. Sounded slightly more "flat" when compared with 1_B, to my ears.
1_B: Lossless. The instrument seperation seemed much cleared to me on this file. Strum quality was quite clear and natural sounding.
1_C: 128 kbps. Sounded more flat, with degradation of the highs when there were multiple instruments playing at the same time (most noticeable at 0:16-0:20)
 
Jan 2, 2016 at 2:54 PM Post #155 of 169
Which MP3 codec was used and which options were selected when making the two files?
 
Jan 2, 2016 at 4:06 PM Post #156 of 169
  Which MP3 codec was used and which options were selected when making the two files?

 
Here are the details:
 
Quote:
http://www.head-fi.org/t/646411/lossless-vs-128kbps-mp3-vs-320kbps-mp3-blind-test/75#post_9362033
 
I used the most recent release of LAME. 3.99 I believe, as it hasn't been updated since October 2011. I can double check to make sure when I get home but I didn't install the software until about a month or so before the test so I'm 99% sure here.
 
It was set to slow speed, high quality. Full stereo. Basically I didn't change anything from default other than the quality slider.

 
dBPoweramp was the application, but I didn't see which version was used.
 
Jan 2, 2016 at 4:35 PM Post #157 of 169
   
dBPoweramp was the application, but I didn't see which version was used.

 
Did you use any of the LAME presets (e.g. V0, V2, etc) or did you just set it all by hand?
 
Oct 30, 2016 at 7:41 PM Post #158 of 169
Nov 3, 2016 at 4:46 AM Post #164 of 169
Depends on the ripped source though.

For example I've used Spotify on max (320kbps ogg) for years.

On a trial right now of Tidal lossless, and there appears to be a massive difference

 
Probably different masters being used.
 

Users who are viewing this thread

Back
Top