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1/3 of People Can't Tell 48Kbps Audio From 160Kbps
An anonymous reader writes "Results of a blind listening test show that a third of people can't tell the difference between music encoded at 48Kbps and the same music encoded at 160Kbps. The test was conducted by CNet to find out whether streaming music service Spotify sounded better than new rival Sky Songs. Spotify uses 160Kbps OGG compression for its free service, whereas Sky Songs uses 48Kbps AAC+ compression. Over a third of participants thought the lower bit rate sounded better."
Are these the same people who prefer MP3 Sizzle?
Remember RFC 873!
(although not as low as 46kbps) and reached the same conclusion. Most people vastly overestimate their ability to distinguish tracks encoded at different bitrates. And I've seen study after study that backs this up. This includes self-professed audiophiles, the original authors of particular tracks of music, and so forth.
Mr. Wizard... why is this place called the Cave of Hopelessness?
So, 1/3 of people eh? Hardly a damning assessment when your sampling size is 16 people. Besides, most people I know including myself have some sort of hearing damage from the past or don't really know what to listen for when presented with different types of sound.
I would be more impressed if the same encoding format was used. I think both samples should have been ogg or aac and not a mix. If comparing aac at 48 and 160 are the results different? Same goes for ogg at 48 and 160?
Do it with 48kbps AAC vs. 160kbps AAC, or 48kbps OGG vs. 160kbps OGG, and you might have something meaningful.
Or, 48kbps AAC vs. 48kbps OGG, and 160kbps AAC vs. 160kbps OGG, if you want a flamewar...
Village idiot in some extremely smart villages.
You blame the sound, I blame the people.
I think they should see if there is a correlation to the preferred quality, and how much auto-tuned "music" the people listen to.
Self proclaimed typo king, and inventor of the bear destroying coffee table (patent not pending).
In a deaf listening test, 100% couldn't tell the difference between a 160Kbps OGG file and a cannon. Though 3% noted the smell of gunpowder.
If the higher compression audio had simply used this $500 Denon ethernet cable, the results would have been different:
http://www.usa.denon.com/ProductDetails/3429.asp
But seriously, can you make a sweeping statement like "People can't tell 48k audio from 160k" if you're also switching compression technologies? OGG vs. AAC is a whole article on it's own, you just muddy the waters by making this about the compression rate.
This is just a new version of the old megahertz myth of the CPU wars. Two different 2GHZ processors from different manufacturers are not equal, we all finally figured that out for the most part, right? Now we've moved onwards... to the Kbps myth?
Thats strange, I find it trivial to identify differing qualities of compression when listening to my music files.
You look down at the UI, and it tells you what the bitrate is.
(Joking aside, I have advocated 128 kbps for years, not because of sound quality issues, but rather because most people own cheap computer speakers and/or headphones. You only get quality as good as the weakest link in the system.)
HA! I just wasted some of your bandwidth with a frivolous sig!
The summary is quite misleading.
It sounds like 100% of the participants could tell the difference between the two encodings, just 1/3 of the people thought the more simple, clean, highly compressed version sounded better. 2/3 of people thought the high bitrate version sounded better.
When choosing compression, the better way to go is to shoot for transparency versus the uncompressed source, not which audio sounds better to your ears.
That's why ABX is the industry standard for compression comparison, not a simple AB test as in this experiment.
Blessed are the pessimists, for they have made backups.
this summary is misleading. they were asked to choose which they thought sounded better. the listeners DID notice a difference between the two, and for some reason 1/3 of the participants enjoyed the lower bitrate version better. perhaps it had less harsh high tones or something about it was more pleasurable to them... that doesn't mean that the higher bitrate didn't honestly sound more accurate to the source material. Perhaps uncompressed audio should have also been incorporated into the test. If they still choose the lower bitrate over uncompressed, then it's clear that some listeners prefer the song with the changes inherent to compression.
this was a very unscientific study, with a very small sample size, and really shouldn't be front page on slashdot.
frog blast the vent core
I used to sell audio equipment as a teenager and I recall different people had different ideas about what constituted quality audio. Some people liked deep muddy base, other people liked loud midranges, etc.. I think the study's conclusion is all wrong... it's not that people can't tell the difference, it's that people sometimes prefer the lower quality bitrate. Personally, I just want things to sound representative of the real-life equivalent. :)
No, just the headline is massively misleading.
The article actually states that people (a) could hear the difference (b) thought the lower bit rate stuff sounded better.
The key being that the two were encoded with two totally different codecs.
Today's low-bitrate MP3/AAC will be tomorrow's vinyl.
I firmly believe that you prefer what you're accustomed to hearing in the first place. Most kids today have grown up hearing nothing better than highly-compressed FM or low-bitrate MP3 music. They don't know anything better, and given the option of hearing better music, perhaps even uncompressed, with a much larger dynamic range and noise floor, they'll gravitate to what their ears and brain have been trained to appreciate.
Tomorrow's world will have "128Kbps MP3 Afficionado" publications extolling the virtues, "warmth", and "naturalness" of the low-bitrate MP3. And audiophiles will pay top-dollar for crippled hardware and overcompressed, undersampled music tracks.
it said 48Kbps, not kHZ.
Most lossy music formats totally submarine a lot of detail at 48Kbps and I would wager that almost everyone has the auditory acuity to recognize it. They simply don't have the mental acuity to care.
I agree, so much auto-tone (big air quotes) "music" and they hardly notice gross clipping and drastic tone flattening. :-)
I paid to get my TV ISF calibrated. It looks amazing. But if you brought it inside a Best Buy and sat it next to their other TVs your average Joe would think it looks like crap.
The TV manufacturers increase the amount of blue to make things appear brighter. People's faces turn green so they up the amount of Red. Then they over-sharpen which introduces artifacts and over-contrast which creates banding.
Encoding audio in a lossy format no doubtingly does the same thing. They make sure the music still "pop"s to the point where it is exaggerated causing the music to "sound" better.
The people who say that 48Kbps sounds better than 160 would probably say the same thing compared to the original.
Since the 16 subjects were asked "which sounds better" and were not given an alternative "there's no difference" then it's actually possible that 12 of the 16 thought there was no difference, and so they randomly picked A or B. And 6 picked A.
So it's possible that only 25% could tell the difference and selected the higher bit rate.
Great study. Very Scientific.
This 'test' seems rather lacking. It doesn't note if the AAC is HE or LC. That can have a very big impact on quality as HE takes more processing power but delivers much better quality at low bitrates. Each codec would also have it's quirks and 'tricks' that establish it's strong and weak points. Some people will simply like one aspect of a codecs compression methods over another, whether that pertains to filterout out high frequency, chopping out repetitive or white noise that is typically not heard, or whatnot.
The fact that they also only tested 16 people should tell the rest of the story. It's not even remotely a good sampling of users and considering the source, it probably consists of users who are 'in the know' about compression techniques and what to listen for.
I would be very interested in a larger study with a random sampling of the users of these two services, with a much larger study group to see what it shows.
This test isn't a complete experimental fiasco (like some of the Microsoft-sponsored listening tests that deem WMA to sound as good at 64k as MP3 at 128k).
But there are a couple of significant flaws with it, that make the results pretty useless:
If you want to know about some methodologically-better comparisons of audio codec quality, please see the Codec listening test page at Wikipedia. Full disclosure: I wrote most of this article, and have attempted to compile the results of all the carefully-conducted independent tests that I could find.
Finally, none of this is to say that we should all demand 160kbps streaming audio if 48kbps can be made to sound just as good. It's just that this study doesn't establish that, not by a long shot. The headline is also wrong in claiming that 1/3 of the participants couldn't distinguish 48k from 160k audio: in fact, they preferred the 48k audio. And preferring one format is very different from claiming that it is of a high-fidelity: for example, audio with a compressed dynamic range is by definition degraded, and yet it persists in commercial rock recordings because uniformly loud music grabs listeners' attention more easily.
My bicyles
I think a LOT of this has to do with so many of today's kids not KNOWING what good sound reproduction CAN sound like.
I've been building my stereo system ever since I was a kid. I walked into a high end audio shop at about age 12...and first heard Klipschorn's hooked to McIntosh tube amp, and I couldn't believe my ears...
It was right then, that I started building my system so I could have that some day. And, today...after buying piece here..piece there, deal on this..selling it and improving one piece at time (ok, thieves and insurance helped with the speakers at the end), I almost have that set up.
People that come over and hear it...are often amazed how good it sounds....they often exclaim they hear new things and nuances in familiar songs they'd never heard before.
Sure, I like an iPod, I have a couple of them...a shuffle for the gym, and a classic for travel, in the car..etc. I have good earphones for them, Shure 530's I think....but, I do realize that these are for very POOR listening environments. I try to get my music in the best source I can (this means CD's at this time, can't buy lossless online yet), I rip them to flac for home stereo usage..and decently high quality mp3 for portable use.
Unfortunately, somewhere between now and when I was a kid...people stopped buying good home audio systems. I don't quite know what or what happened. Somewhere along the line...ONLY portable players came into vogue...and it is sad that so many are losing out how good sound reproduction can be. I dunno if it is cause or effect....but, so much of todays music is mixed so poorly, overly compressed with no dynamic headroom anymore. So, maybe there isn't much point to getting good gear, if new music is no longer mixed to get the most out of it.
But, as far as good gear goes....you needn't go overboard on the super audiophile non-sense and voodoo that is out there, but, with respect to solid audio gear...to a certain extent, you do get what you pay for...
Light travels faster than sound. This is why some people appear bright until you hear them speak.........
Unfortunately, somewhere between now and when I was a kid...people stopped buying good home audio systems. I don't quite know what or what happened.
Maybe they didnt enjoy it.
Why do you think people enjoy music and songs ? Most likely, not because its reproduced faithfully, or because they care about the nuances.
Almost nobody cares about the nuances, they like beats and bass or dancy tunes, gansta lyrics or love stories, stuff that is accessible and they can relate to.
Sure, some people care about that little uptick from the violin on the 3rd measure of the 6th symphony of whoever that you can only hear with an hi-fi system in a quiet room. But most people just listen to music to either give them some energy for their workout, have fun at parties or concert, or drone the sounds of their miserable commutes, dreary jog run or boring life.
Same reasons people eat fast food instead of fine cuisine I guess.
I grew up in the 80s and early 90s and most people I knew just had off-the-shelf radio/cassette/record-players from Target or wherever. Myself included. And the music always sounded good enough. It still does. I had a couple friends who turned audio hobbyist but I never saw the point. They spent loads of money and seemed to enjoy the music less.
And nowadays, emphasis should really be on enjoying music live, anyway. I might be wrong but I expect distribution will bring less and less money, but not less fame - and fame will bring performances and money.
If I want to carry my favorite artists with me, or listen to them at home, I have bigger things to worry about and spend on than the quality of the audio. Good enough is good enough for that.
Not all bits have equal significance. Example: Suppose I have a perfect-fidelity 30-second recording of a pure 440 Hz sine wave. On a CD this would require 16 bytes/channel * 2 channels/sample * 44,100 samples/second * 30 seconds = 42,336,000 bits.
This same signal can be compressed to the formula "L(t)=R(t)=sin(440*(2*pi)*t)*u(30-t)" (where u(t) is the unit step function { 0, t=0 }). Using string representation, this compressed version requires 25 bytes, or 280 bits. In other words, we eliminated 151,199 of every 151,200 bits—and the compressed version actually has better fidelity than the CD version, since it can be losslessly decoded to an arbitrarily high sampling rate.
This is obviously a contrived example, but it suffices to demonstrate the reducing the bitrate, even drastically, does not have to negatively impact the quality of the audio.
"The state is that great fiction by which everyone tries to live at the expense of everyone else." - Bastiat