Blind Test: mp3 vs. 24bit

Hello Audiogon Members~
PMA magazine is conducting a study to see if we can hear which is better between an mp3 and a 24/96 file in a side-by-side comparison. So far, the results are surprising. If we all participate, we’ll know the truth. It’s also a fun test. Please go to the page below to participate:

(1) the build quality and matched resolution capabilities of your audio system  will be a key decisive factor in weeding out the winning contender from the pretender (.Its not just the dac ...its the whole shebang  including cables). I recently upgraded the ICs from the dac to the amp to a CARDAS CLEAR model and the improvements were graphic:. ( stop the sibilents and that digital "raw edge". an improved soundstage , more slam,  punch and dynamics. )

2) the quality of the recording and skill of the recording engineer in mastering the digital recording is a key factor across all versions.
(3) no need for me  to go to a 3rd party blurb ... I have an assortment of  of the same digital recordings in various bit rates to give me the direct shoot-out test results. [  (i) mp3, (ii) 16/44, (iii) 24/96 and (iv) 24/192 ]. 

My take: Not even close...In any case the audio performance improvements are progressive:in lockstep with the bit rates.
- The better the bit rate recording played on a high-end system  the better the  audio resolution and performance.
- At the extremes it is graphic.  
I downloaded the files and they are all identical WAV files none of them are MP3s so there is no test to take.
"So far, the results are surprising"

I’m not surprised.

Although many people apparently find 128kps indistinguishable from CD, for me once I get past 192kbps it becomes extremely difficult to tell any difference.

Not to say it also defeats the purpose of
enjoying the music.

Listening to music should never be about straining to hear minute differences, should it?

It’s quite a large file (190mb), so I might have a go later on my PC.

Ok, done the test on headphones and in all 3 cases (Black Sabbath, Patricia Barber, Anne Akiko Meyer/Vivaldi) I marginally preferred sample a over sample b.

Let's hope the findings are better than a 50/50 or 60/40 result.
Way better.
I emailed Rob Schryer who nicely responded obviously I'm not a huge computer guy and the MP3s are disguised as WAV files duh. Some slight differences on my crappy laptop speakers but uploading them to my NAS to listen on the big rig.
Close but the discussed mp3's are not quite as good on my system. I'm curious, what's your point of this comparison? 

Hello everyone! The results are out. The 24-bit was chosen correctly about 53% of the time, which means 47% of the answers were wrong. This is coin-toss territory. You can read the full summary here: 


Wow, that’s close.

When you consider the fact that the MP3 versions were between 220~260kbps, and not the highest available, 320kbps, then you can see the disparagement of MP3 for what it’s worth.

As I said 12 months ago, it would appear that once you get above 192kbps it becomes very difficult to distinguish MP3 from anything higher.

Even all the way up to 24/96!

I find these A/B tests futile. The real test, at least for me, is to listen to a familiar song/album at the higher resolution, then the same at the mp3 (or whatever). Your ears will tell you which is the lesser quality - the song won't sound "right", maybe a little fuzzy or maybe missing some detail. This approach also works with streaming - stream a familiar song and I can hear a subtle difference vs a cd, etc, although equipment may play a bigger role in this than the actual resolution. just my 2 cents.

I did get all three choices correct, but even on my home system the differences were close. Focusing on a specific voice or instrument was how I decided on the difference between the tracks. My impression is that the recording quality has usually been a more significant factor for sound quality than the resolution of the file.

Also, one difference that seems more apparent to me when comparing hi-res files vs MP3 files are spatial cues and "air" around voices and instruments. These are more audible to me when listening via speakers and less so via headphones.