High bitrate MP3 vs. Lossless ABX Tests?, Are there any studies...? Options

[Street Samurai]

Hi All,

I've been corrected before on this site for making the statement: "I can tell the difference between an MP3 and lossless". I've never ABX'ed myself but I was wondering if there has been a statistically significant (with regard to population) ABX study done with (say) Lame insane vs. Lossless?

Clearly for myself it makes more sense to do a personal ABX but I was wondering in general about the population.

I searched manually through the posts in this forum (since search seems useless for the term 'mp3') and didn't see anything.

Thanks for help,

ss.

This post has been edited by Street Samurai: Jun 2 2005, 01:02

[Jebus]

To summarize:

a) A "lossless to high-bitrate MP3 ABX" test = a "high-bitrate MP3 ABX" test. No need to specify lossless, all ABX tests are done against a lossless source by definition. A test comparing two codecs (again, against a lossless reference) would be an ABC test.

b) Even the 128kbps tests usually come up with statistically insignificant results because the public just isn't able to distinguish. So the only way you'll ever get interesting results at high-bitrates is to either do it yourself, or read the results of someone who did. Guruboolez is about the best person here for this sort of thing... he can tell the difference on some problem samples, but not must samples.

This post has been edited by Jebus: Jun 2 2005, 21:33

[Zurman]

To summarize:

a) A "lossless to high-bitrate MP3 ABX" test = a "high-bitrate MP3 ABX" test. No need to specify lossless, all ABX tests are done against a lossless source by definition. A test comparing two codecs (again, against a lossless reference) would be an ABC test.

No
mp3 ABX test does mean ABX vs original source (or lossless, it's the same), but nothing prevents you from ABXing mp3 vs mpc, mp3@128 vs mp3@256 and so on...

b) Even the 128kbps tests usually come up with statistically insignificant results because the public just isn't able to distinguish. So the only way you'll ever get interesting results at high-bitrates is to either do it yourself, or read the results of someone who did. Guruboolez is about the best person here for this sort of thing... he can tell the difference on some problem samples, but not must samples.

True.... Even in this forum, which probably is the place where most motivated and skilled people can be found, 128> listening tests don't involve many people, because all codecs are nowadays excellent (I didn't say perfect, or CD quality...) at any bitrate >= 128...

[Jebus]

To summarize:

a) A "lossless to high-bitrate MP3 ABX" test = a "high-bitrate MP3 ABX" test. No need to specify lossless, all ABX tests are done against a lossless source by definition. A test comparing two codecs (again, against a lossless reference) would be an ABC test.

No
mp3 ABX test does mean ABX vs original source (or lossless, it's the same), but nothing prevents you from ABXing mp3 vs mpc, mp3@128 vs mp3@256 and so on...

Okay, fair enough - around here, the ACCEPTIBLE process is to ABX vs the original, since ABXing two different lossy codecs doesn't tell you much of anything, just which one sounds better to you (which could be the OPPOSITE of which one is closer to the source. Some people like the sound of certain codecs).

[stephanV]

Okay, fair enough - around here, the ACCEPTIBLE process is to ABX vs the original, since ABXing two different lossy codecs doesn't tell you much of anything, just which one sounds better to you (which could be the OPPOSITE of which one is closer to the source. Some people like the sound of certain codecs).

No this is not correct... ABX tells you *nothing* about your personal preference. It only tells you can hear a difference between the two files you are ABXing. While you can ABX two lossy files against one another, after doing this you can only show people that you can hear a difference between the two files, not which one you prefer.

[edit] removed some unclarities

This post has been edited by stephanV: Jun 2 2005, 23:31

[Pensive]

I'm new, hi everyone, i want to make a suggestion on this subject.

This is my slant:

In a few years ill be buying either an sacd or dvd-a player depending on the climate, which of course will be a wireless device and send the digital data straight to the amplifier, which will also be wifi connected to my media storage device, containing my music collection, very likely with storage in the realm of terabytes.

When i play my SACDs, and then flip to my mp3 encoded tracks, they are going to sound terrible. Even cds will begin to sound a little lifeless. I'm putting all my CDs on my HD with Flac, and thats that - it makes sense for the future, sooner or later we'll all have media devices instead of dvd players.

Don't spoil your expensive systems you'll buy in the future with a poor substitute for lossless when hard drives are getting so cheap and so big.

Soonish, I'm going to mirror raid myself up a terabyte archive beast (current costs = 8*250 gig HDs - Im waiting till i can run 4*500 gig hds without breaking the bank) and once ive got that there is no excuse for worrying about the space my music collection takes up. Some of you may have enormous collections, which causes a problem, but i still like the idea of wifi music throughout my house at CDDA quality with no cds in sight!!

This applies in this thread because I think these days we should be trying move away from lossy over processed codecs, to take advantage of this cheap storage with the highest quality media. What you pump out to portable devices could very easily be done in realtime, and set to encode different bitrates dependant on the device. So your ipod, your car and your house can sync up the audio library, but in whatever bitrates is best for that device. Maybe, 320kbit in the car, 192 on the ipod, reflecting available storage on media devices.

When this sort of system becomes available, you'll want a good quality source.

Just my perspective, in respect of yours

This post has been edited by Pensive: Jun 3 2005, 00:20