Quote:
Originally Posted by
cel4145 
Go do your own research and find the studies which show that many people can't tell the difference between low compression files vs lossless.
Done it. How do you think I formed my opinion? Oh, perhaps I have an Apple bias? Yea, don't think so. It's not as simple as how many people can't tell the difference between low compression and lossless. It's a question of degree, and how you define low compression.
Interesting that while YOU are the one saying my opinions are wrong, You are also putting the burden of proof on me. Usually, the guy saying the first guy is wrong proves his point, not the other way 'round.
I actually spent some time searching for studies on the perceptual evaluation of codecs. There are many good papers, but most if not all compare a particular codec to audio not so encoded. And most are written to prove the efficacy of a particular codec. I have not found a formal paper that definitively supports the number of people that can or cannot detect a particular codec at a particular bit rate. I did, however, find this somewhat less than academic report - below.
I provide this links with these comments…er…my opinions:
The test sample is a little small, but adequate at 30 people. The tests were presented on headphones only, but IMHO (will that suffice?) the Sony MDR-7506 headphones are quite unforgiving and revealing of audible flaws. The are one of the more musically unforgiving headphones, which makes them great for analytical listening, but not exactly fun. If anything they probably made the testers hyper-sensitive to audible anomalies. AAC was not tested at bit rates higher than 128Kbps, and the Test Results chart therefor shows only three data points for AAC. Oddly, several of the other codecs are also missing data points, so a detailed comparison is not possible. In the chart "How The Formats Compare" we see AAC already at a 4.8 at 128Kbps (5=identical to original CD), with no test data for 256Kbps, much less 320Kbps which I have suggested. We could extrapolate that given higher data rates the AAC codec might have scored a 5, but that would strictly be conjecture.
http://pcworld.about.net/news/Oct022001id64123.htmQuote:
Originally Posted by
cel4145 
As for those that prefer the sound of AAC vs MP3, you can people find people arguing about that all over the web (well, unless you hang out mostly on Apple forums).
The above link isn't on an Apple forum, and does represent at least an attempt at an objective double-blind test, if incomplete.
Quote:
Originally Posted by
cel4145 
If you prefer the best AAC encoding over MP3, then state that as an opinion.
OK, done. But again I doubt that will stop you from arguing with me.
Quote:
Originally Posted by
cel4145 
Don't mislead people to think that just because AAC shows a little less data loss than MP3s (which it does) that it's somehow superior in SQ. More lossy in data loss does not necessarily mean more loss in perceived audio.
I'm not attempting to mislead people into thinking anything. Oh, forgot I'm your bad guy.
The above statement is my opinion. In my opinion, at least.
Here ya go:
http://en.wikipedia.org/wiki/Advanced_Audio_Coding
Did you happen to notice AAC's parentage? Hmmm…lets see now…"AAC was developed with the cooperation and contributions of companies including AT&T Bell Laboratories, Fraunhofer IIS, Dolby Laboratories, Sony Corporation and Nokia. It was officially declared an international standard by the Moving Picture Experts Group in April 1997."
What? No Apple? OMG!
Quote:
Originally Posted by
cel4145 
A prime relevant example is that MP3 VBR V0s are often found to be equal in SQ to 320kbs MP3s. It's the difference in the encoding process. Simply which one has more of the same data left in comparison to the lossless file is not a good measure. And yet, people like you and other Apple advocates, mislead people to believe that AAC is better just because of that reason.
I regret to inform you that you have just voiced your opinion, not stated fact. Please clarify your statements with a disclaimer when they are comprised of your opinion only.
I make no attempt to mislead. I am not strictly an Apple advocate, and the reason you state…that AAC has more of some data left in comparison to the lossless file…is NOT my primary reason for my preference of AAC over .MP3.
Quote:
Originally Posted by
cel4145 
Audio perception is the only factor that matters here.
Agreed, if we change that sentence to "Perception of Audio Quality is the only factor that matters here."
Quote:
Originally Posted by
cel4145 
What's important is what is lost
No, thats not it...
Quote:
Originally Posted by
cel4145 
and how that loss is perceived, not so much how much is lost.
That's it…
I will have to disqualify any VBR file as being inappropriate because of what it does to the ability to fast-forward. VBR files confuse many players because, well, the bit rate is variable. For example I have dozens of .mp3 VBR files that are all 55 minutes in actual length, yet if you grab the play slider and try to go to, say, the 30 minute mark, you can't. You can get about 17 minutes or so in then the player is lost as to where it actually is in the file. I've found this true on all VBR files, on many players - haven't tried them all, so sorry. It seems the common technique is to use the file size and bit rate to derive play head position. A VBR file will simply confuse this calculation. It adds a rather unpredictable inconvenience to the whole mess, though yes, VBR sounds subjectively better for it's average bit rate. But that's the key. You are't always listening to the average bit rate! Joint Stereo has some merits too, though it also has a sonic impact. How's half the file size sound? That's true if the file is mostly mono, but I never…ever… use Joint Stereo.
The above paragraph is my opinion, based in facts collected by my own observations. In my opinion, at least.
Quote:
Originally Posted by
cel4145 
Now perhaps I was too hasty in accusing you of intentionally spinning for Apple. Maybe you don't realize that this is the "spin" over why AAC is better?
Spin…I assume you mean "a particular viewpoint or bias". You do get that this is a forum, right? This is a place where people express opinions. If my opinion (or viewpoint) is biased, that implies a bias in a direction other than what the opinion would be were the one with the opinion be completely truthful.
Yes, I'm biased. Highly so. I'm biased to discover the truth. I have been for my entire career in audio.
I've been listening to bit-rate reduced audio since the early 1980s, long before most current .mp3 listeners were even conceived. I've heard the effects of just about every bit-rate reduction scheme many times, and worked with professional audio software that had the ability to select bit rates, codecs, and all the permutations. I've even studied the effects of sequential re-codeing, passing already bit-rate reduced material through another (different) codec. Yes, done the research, but I don't need to prove it to you since you wouldn't believe me anyway. I've selected 320Kbps AAC as my codec of choice when I must use some form of bit-rate reduced file because,
in my opinion, it's more transparent than .mp3, an opinion not arrived at casually.
But of course, the above paragraph is also just my opinion.
As to being an Apple proponent, let me just give you a perspective on where I'm coming from. I've actively used many OS's:
Unix
Xenix
DOS
CP/M
Apple ][ DOS
Mac OS from System 3 thru current
Windows from 3.11 thru Win 7 - sorry, no Win 8 yet.
When I say "actively used", I mean used on a daily basis to accomplish productive work, not just tried it out recreationally. Administrated networks, designed and constructed audio editing suites, production and broadcast facilities. I've used Windows and Mac OS computers for audio production applications since 1988, in one form or other. I've evaluated audio CODECs in the context of voice and music transmission systems, recording systems, and broadcast systems. I even mounted a brief, but failed campaign for "No Bit-Rate Reduction" at a time when it was just becoming popular. By the way, Bit-rate reduction is technically more correct than "compression", as you can have data compression without data loss, but to change the bit-rate, you have to throw something away. And I first played stereo 15KHz bandwidth audio off a hard drive in 1984.
I doubt this background will improve our adversarial relationship, but I post it to show I've used both Windows and Mac platforms for over 26 years, not just for a few months. I hated them both, loved them both, and felt indifferent too. But over the years I've had to be objective and apply technology to solve problems in the best way possible. I've seen good, bad and ugly solutions on all platforms.
DO you still think I'm "spinning" to Apple? You're right, in the context of this thread I am. And I have my reasons, which would mean nothing to you, and I'm not going to detail them here. Suffice it to say, the preference was not arrived at casually, or with a mere 8 month cursory brush with the OS and software.
Oh, but the above is just my opinion, don't ANY body take anything I say as fact! I could be wrong.
You may, once again, fire at will.