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MacBytes
Jul 5, 2004, 03:01 PM
Category: News and Press Releases
Link: iTunes \'not CD-quality\' (http://www.macbytes.com/link.php?sid=20040705160152)
Posted on MacBytes.com (http://www.macbytes.com)

Approved by Mudbug

The Cheat
Jul 5, 2004, 03:07 PM
Well, thank you Captain Obvious.

jholzner
Jul 5, 2004, 03:22 PM
Well, thank you Captain Obvious.

LOL...you beat me to it :cool:

GaelDesign
Jul 5, 2004, 03:25 PM
What is this? The Boss Zone in Dilbert?
Compressed audio isn't fully CD-quality. Um, duh. And double duh. Talk about stating the obvious.

Frankly, AAC at 128Kbps created by a good encoder is close enough to the original CD-quality audio that most people wouldn't notice unless they did careful A-B tests on a really high-quality stereo. I'm a pro audio engineer, yet I buy AAC tracks on iTunes and listen to them on my iPod because CD-quality audio in that situation isn't noticeably any better. And iTunes is damn convenient.

Move along folks, nothing to see here...

Jared

Neuro
Jul 5, 2004, 03:29 PM
Heh, like duh. He could have redeemed himself by saying 128Kbit AAC sounds better than other commercial codecs at the same bit rate.

macridah
Jul 5, 2004, 03:52 PM
How does wma or sony whatever format compare to aac? itunes never claimed cd-quality, they always said near cd quality music. I do notice that aac sound better than anything i rip from my cd or downloaded from any p2p. The guy that wrote the article must be a hater. itunes rock on.

0 and A ai
Jul 5, 2004, 04:05 PM
How does wma or sony whatever format compare to aac? itunes never claimed cd-quality, they always said near cd quality music. I do notice that aac sound better than anything i rip from my cd or downloaded from any p2p. The guy that wrote the article must be a hater. itunes rock on.

Yeah he must be a hater.

matthew24
Jul 5, 2004, 04:18 PM
I agree with the author, Apple should move to at least, to 192Kbit.

I did once encode a CD to 128Kbit and decoded it again, the difference between the original and the encoded/decoded copy was just too big.
Apple should do better for a dollar a song. At this moment I do rate the quality they offer at 60/70ct for each track. So I am still going for CD's.

crenz
Jul 5, 2004, 04:27 PM
Hopefully more people will criticize them for that, and also for the DRM. I will continue to buy mostly CDs (instead of downloads) until I can get losslessly compressed audio at least at CD-Quality (48Khz/24 Bit would be nice, though) and without DRM as a digital download.

nuckinfutz
Jul 5, 2004, 04:28 PM
LOL "CD Quality" as if there's some sort of certification process that sets a baseline of CD quality. I've 300 CDs and I can tell you...no show you CDs that sound like crap and some that sound magnificent. AAC is definitely better than CD Quality because no such "magical mark" exists.

yamabushi
Jul 5, 2004, 04:34 PM
Rather than increase the bit rate significantly I think Apple should offer CD-quality (or better) versions of songs as downloads in addition to standard 128bit AAC. They should also sell CDs by mail bundled with the same album as AAC for download.

Sayer
Jul 5, 2004, 04:34 PM
In other news, the Earth revolves around the Sun and the Sun is not the center of the known universe.

nuckinfutz
Jul 5, 2004, 04:35 PM
Hopefully more people will criticize them for that, and also for the DRM. I will continue to buy mostly CDs (instead of downloads) until I can get losslessly compressed audio at least at CD-Quality (48Khz/24 Bit would be nice, though) and without DRM as a digital download.

Prepare to wait. Your great great great grandchildren are going to love those features :P

Oh yeah and why do I hear consumers bragging about 24bit/96k soundblasters cards. ROFLMAO....come'on people you don't actually think you're hearing 24bit audio do you? Haven't these people ever looked and said "geez why does an Apogee 24bit converter cost $3500 when I got my 24bit Audigy for $150?"

Now we have the same consumer pontificating about the merits of 128k AAC files being played on the crappiest of headphones or speakers. Please wake up from lala land. Yes I believe you can tell a difference on some songs. Perceptual encoders offer varying performance depending on musical content but the end result is pretty damn good. After all the typical consumer seems to place a priority on high quality video over audio. How many times have you seen a nice big screen TV with a cheap "home theater in a box" setup. I've seen it far too much.

nuckinfutz
Jul 5, 2004, 04:37 PM
Rather than increase the bit rate significantly I think Apple should offer CD-quality (or better) versions of songs as downloads in addition to standard 128bit AAC.

Folks that no go. The RIAA is not going to license lossless music. AAC offers us low cost access to music that does sound better than CDs did just 5 years ago but if you want the pinnacle in soung you have to buy the CD.

King Cobra
Jul 5, 2004, 04:46 PM
From the article
The New York Times advises: "Love the iPod, but don't jump too hastily to fill it with thousands of dollars of iTunes. The tracks are not carbon copies of the CD originals, but compressed versions.
To the New York Times: Don't fill your iPod will completely uncompressed versions of the songs. You will drain your iPod's battery.


Also from the article
In order to create a small file, Apple uses "an extreme form of compression that takes a sample of the sound at intervals," explains the report.
Wrong. 128Kbps isn't an extreme. The lowest you can encode from iTunes is 16Kbps, so 128Kbps hardly sounds like an extreme. And with LAME encoders, I think you can do less than that. Also, Sony uses a form of compression, as well. And then there's mp3, MPEG-2.5 audio, etc.

Now this proceeded to piss me off:

Also from the article
"The bit rate for iTunes, 128, is so low that when played side by side against the original, the difference is audible not only to audio enthusiasts, but also to mortals with ordinary hearing," reporter Randall Stross claims.
What the hell do you define as a mortal? Point one out to me! Besides, Sony's format, ATARTC-3 (or whatever it is) is way worse than AAC at 128Kbps, because the Sony format recompresses already compressed music into 48Kbps, I think. Hey, Stross, that would sound so bad in the same side by side test against the original -- or even the first compression, OR 128Kbps AAC -- that it would make mortals cringe in their sleep. Take that, you damn PC zealot. http://www.thetechpub.com/phpBB2/images/smiles/icon_twisted.gif http://www.thetechpub.com/phpBB2/images/smiles/new_snipersmilie.gif

Note to self: Never trust a report from Randall Stross again.

nuckinfutz
Jul 5, 2004, 05:21 PM
I didn't even bother to click the link. Why in the world would I take audio advice from a writer for the NY times? They need to stick to spouting their liberal crap and leave the technical stuff to others.

In order to create a small file, Apple uses "an extreme form of compression that takes a sample of the sound at intervals," explains the report.

What a dumbass. That's "Sampling Rate" you doofus. AAC compression analyzes the music and decides what data can be stripped because the ear is unlikely to hear sounds that are masked. That's a crude explanation but at least it is in the ballpark unlike this guy.

fraeone
Jul 5, 2004, 05:33 PM
Crap on NYT, crap on the writer, or whatever, but COME ON. What's wrong with asking for better quality. The difference between a 128kbps AAC rip and a real CD should be audible to anybody. At least give us a choice between 192 or 256 and 128. I'm not of the opinion that lossless is worthwhile (yet).

jbembe
Jul 5, 2004, 06:22 PM
Hmmm, let's see. Apple starts offering lossless music.

Whine&Complain Gallery: Beware, downloads take over an hour, so iTMS sucks.

File this under caveat emptor to people who don't really know what a MP3's are. For the rest of us, this guy at NYT appears to need a new vocation.

bertagert
Jul 5, 2004, 06:54 PM
So, lets see, all the millions of AAC & MP3 files people download from itunes and P2P networks are no good? I'm not saying that original CD quality isn't better than MP3, AAC or WMA. I'm saying, people aren't caring about the quality so much. They like the convience of getting these compressed files and how nicely all of them can fit in the palm of their hand. Writers like this guy really need to investigate the story so they can give the over all picture. A report like this one should be targeted to audio files as they are the ones that care.

On a side note: Haters of iPods don't get it when they write stories like this. Even though they're blasting Apple, they're actually advertising the ipod.

dashiel
Jul 5, 2004, 07:01 PM
just because a 'mortal listener' can tell the difference between 128k compressed audio and uncompressed, does not necessarily mean they can tell which one sounds better.

audio compression is a lot like wine. sure i can tell there is a difference between a $5, $50 and $500 bottle of wine, but in a blind taste test i could probably tell you that the $50 was better than the $5, but that's about it. after wine gets above $10 i just don't have the experience or knowledge to determine what is a better wine. i'd be willing to bet 90% of the population is the same way and that the same holds true for audio.

put on an AAC encoded track, an MP3 and an unencoded on the average persons stereo, in the average listening environment and i'd bet dollars to donuts they wouldn't be able to tell you definitively which was which.

apple and the average consumers doesn't care that you can hear minute differences in audio quality when you listen through a linn hifi with ribbon speakers and $30 a foot monster cable.

Keynoteuser
Jul 5, 2004, 07:06 PM
I want Apple to add a REAL music store to the system, and let you pay a few bucks extra to download NOW and also get the CD mailed to you. I'd pay $12 or $13 to get the songs now at 128 and also get a CD in a week or two. Heck, they could join up with Amazon to provide the fufilment system. I think this would be the ultimate music store.

ITR 81
Jul 5, 2004, 07:29 PM
For folks that want higher bitrate or lossless all I can say:

You'll have to wait until over 60% of US gets boardband if not more.

I want broadband but all I can get is Dish Broadband for around $60 a month.

yamabushi
Jul 5, 2004, 09:36 PM
I want Apple to add a REAL music store to the system, and let you pay a few bucks extra to download NOW and also get the CD mailed to you. I'd pay $12 or $13 to get the songs now at 128 and also get a CD in a week or two. Heck, they could join up with Amazon to provide the fufilment system. I think this would be the ultimate music store.

That is precisely what I was suggesting. :) Actually, this would probably be an adequate solution for audiophiles as well since they would then be able to rip the CD later at higher quality settings.

SiliconAddict
Jul 5, 2004, 11:16 PM
For folks that want higher bitrate or lossless all I can say:

You'll have to wait until over 60% of US gets boardband if not more.


We are already over 50% and I think that report came out last spring/summer.

nagromme
Jul 5, 2004, 11:37 PM
From my own experience, I believe that almost all the problems people hear with iTunes (and some of this may apply to iPods) is NOT the fault of the AAC, but rather is Apple's fault in the way effects are applied--and you can fix that!

iTunes has several effects that can boost the amplitude of music: Soundcheck, Sound Enhancer, and Equalizers. All three cause problems. The first two can be turned off in iTunes Prefs. Equalizer settings you can fix yourself: just lower the pre-amp slider below 0, just as far as the highest equalizer slider is above 0.

The problem with all three, in my experience (with some educated guesswork)--is that digital audio maxes out or "clips" (which can sound like crackling) when raised too high before conversion to analog (a.k.a. in the computer before your line-out). Apple should be smarter: they should always LOWER and never RAISE amplitudes. The effects would then give you less volume but without the clipping. No problem then--just turn your speakers up.

I have tested all three individually, and ANY of the three effects can cause crackling. Do yourself a favor and turn them off, or use the pre-amp in the case of equalizers. (iPod's built-in equalizer may or may not share this clipping issue... Anyone know? I hope not, since you can't use custom equalizer settings with current iPod software.)

BTW, Crossfades don't raise levels--so that's harmless. (And would be another nice addition to the iPod before I buy mine :) )

Given all that, yes of course there is also SOME difference between AAC/MP4 compression and lossless compression--that's why Apple Lossless exists. But can you really hear it when testing blind?

I'd have to have really good hearing, special training, top-end speakers properly connected to a high-quality amplifier, and be paying close attention in a silent listening environment to actually notice these issues, much less care. And I STILL probably wouldn't notice UNLESS I heard both versions side-by-side. My actual music listening is generally in FAR from ideal circumstances, though, and even listening in silence with headphones, my ears haven't been able to tell AAC from CD. I notice defects from the speakers, noise outside, even problems in the original CD recording itself--but I notice nothing different from the original CD vs. the AAC. I think that's true of most people. (I sometimes hear a defect and want to blame AAC... then I pop the CD in and invariably I hear the same defect--I'd just never noticed before.)

I do dislike the "idea" of compression, on principle. It bugs me, the way getting a JPEG from a client instead of a TIFF bugs me--even if I can't spot any defects. For my favorite groups, I often choose the CD for that vague reason. But generally I can get over the "on principle" discomfort for the sake of fitting more music into less space, downloading it faster, and playing it with less battery drain. Thus, even my CDs are ripped to 128 AAC, and I'm more than happy using my PowerBook as my home stereo.

I suspect a lot of people's objection to compression is like mine--it's "on principle" rather than genuinely sounding bad to them. So they're psychologically predisposed to make themselves hear defects.

Try a BLIND comparison with the above iTunes-settings factors eliminated. VERY seldom do people do a blind test, not knowing which they are listening to. I think if they did, almost nobody would complain.

FYI, some links to AAC compared to other formats:
http://www6.tomshardware.com/consumer/20020712/2u4u-05.html
(AAC shown to be a more faithful reproduction than WMA--and MUCH better than MP3.)
And:
http://www.rjamorim.com/test/aac128v2/results.html
http://www.rjamorim.com/test/multiformat128/results.html
From those listening tests, even 132kbps ATRAC3 is poor quality--to say nothing of the 48kbps Sony sells via "Sony Connect!"

In closing, one more factor: even if you're the rare person who can tell the difference, that doesn't mean you are hearing a "problem" or a "defect." You'll hear a difference from one speaker to another, one stereo to another, one room to another, one format to another... different frequencies emphasized, etc. You may like one sound better than another. You may like AAC better than the raw CD--I've read that blind tests DO often come out that way! It's largely personal taste--and the difference is utterly swamped by your own setup's variations anyway--things like the equalizer on your stereo.

So the "defects" that expert audiophiles may hear between CD and really good compression like 128AAC/MP4 aren't generally crackling or something totally missing. It's something emphasized or de-emphasized differently from the original. Another case where I wouldn't like that "on principle," but in actual practice it's trivial. Zero effect on my music enjoyment.

(And if I COULD tell a defect, I still wouldn't want the time/hassle/bother of buying a whole CD for the one good song :) )

Victoriatus
Jul 6, 2004, 08:10 AM
I did once encode a CD to 128Kbit and decoded it again, the difference between the original and the encoded/decoded copy was just too big.

Classical music might do that, but especially with mainstream music you really can't hear the difference. Also iTunes has done better in AAC ripping as it has matured. The new versions do an astonishing job compared to the older ones with AAC. The same goes for MP3 too. I once did an a/b/c test in MacCentral forums, and I'll post it here again. Feel free to take it if you have time and bandwidth. I took the test myself with a $10000 audio setup with both speakers and headphones, and I couldn't tell the difference, except that with just a couple of files with the lowest bitrates.

---

I've made available three sets of 20 second long audio clips. The second of these sets includes three files: a, b and c. One of the files is an original AIFF as ripped by iTunes. One of the files is this AIFF converted to 192 kbps MP3 by iTunes, and then saved back to AIFF in order to disguise it. One of the files is the AIFF converted to 128 kbps AAC, then saved back to AIFF.

The first and third sets include six files: a, b, c, d, e and f. One of the files is an original AIFF as ripped by iTunes. One of the files is this AIFF converted to 192 kbps MP3 by iTunes. One is an 80 kbps VBR MP3. One of the files is an AIFF converted to 128 kbps AAC. One is a 96 kbps AAC, and one is a 64 kbps AAC.

All the ripping and lossy conversion was done in iTunes, the test should demonstrate a basic setup. No fancy special software. (I'd say Apple's iTMS 128 kbps AACs should sound better than iTunes's 128 kbps AACs.) Because iTunes conversions change the length of the clips, I cropped them back to almost the same lenght to make it impossible to see MP3s and AACs by looking at the file size or clip length. Editing and saving in AIFF was done in Peak LE.

Set 1 is "Niobe" by Dargaard
Set 2 is "Neurasthenic Cellar Diva" by Servovalve
Set 3 is "What a Wonderful World" by Nick Cave & The Bad Seeds (feat. Shane MacGowan)

The files can be found in http://www.ee.oulu.fi/~mercury/soundtest/ . 10 MB per set of three and 20 MB per set of six. Option-click in Safari to download. Drag into iTunes to listen. Or any other way.

There's no need to test all sets. Post your guesses below. Example:

2-a : AIFF
2-b : AAC 128
2-c : MP3 192

...or...

3-a : AAC 128
3-b : MP3 80
3-c : AIFF
3-d : AAC 96
3-e : MP3 192
3-f : AAC 64

...or just name the one(s) that sound very lossy and the one(s) that sound "CD quality".

If you can't hear any differencies or the ones you hear don't bother you, there's nothing wrong with you. Even the 64 kbps AACs sound excellent and are very hard to distinguish.

In case of interest, here are Apple Lossless compression ratios for the full songs in question:

Set 1: "Niobe" down from 1411 (AIFF) to 739 kbps (52% of uncompressed size)
Set 2: "Neurasthenic Cellar Diva" down to 660 kbps (47%)
Set 3: "What a Wonderful World" down to 794 kbps (56%)

Victoriatus
Jul 6, 2004, 08:19 AM
We are already over 50% and I think that report came out last spring/summer.

That is the percentage of people who can use broadband either at home or work. The home broadband penetration in US is one of the lowest in the world, counting the western countries where broadband is widely available, but the work broadband penetration is excellent. Holland, on the other hand, has the highest home broadband penetration.

So, unless people generally shop for iTMS songs at work in US, there's not a very large market for higher bitrate or lossless downloads.

themadchemist
Jul 6, 2004, 08:39 AM
I want Apple to add a REAL music store to the system, and let you pay a few bucks extra to download NOW and also get the CD mailed to you. I'd pay $12 or $13 to get the songs now at 128 and also get a CD in a week or two. Heck, they could join up with Amazon to provide the fufilment system. I think this would be the ultimate music store.

That would come WAAAAY too close to violating their settlement with Apple Records. At least, close enough for Apple Records to sue again. "It's one thing to sell music in a digital format, but actually selling CDs? Come on guys, time to sue Apple Comp. again!"

shamino
Jul 6, 2004, 11:48 AM
I did once encode a CD to 128Kbit and decoded it again, the difference between the original and the encoded/decoded copy was just too big.
With what codec?

128K AAC sounds a lot better than 128K MP3. And an AAC encoded by Apple (sold via ITMS) sounds better than an AAC I rip myself in iTunes.

Sure, nothing compressed will sounds as good as the original, but simply stating a bitrate without mentioning the codec (and the software/site that did the encoding) is not very useful. What codec and what software did you use to generate your 128K bit encoding that you had to redo?

shamino
Jul 6, 2004, 11:55 AM
I want Apple to add a REAL music store to the system, and let you pay a few bucks extra to download NOW and also get the CD mailed to you. I'd pay $12 or $13 to get the songs now at 128 and also get a CD in a week or two. Heck, they could join up with Amazon to provide the fufilment system. I think this would be the ultimate music store.
Why not just buy the CDs in stores for the same $12-13 and eliminate the middleman? :rolleyes:

shamino
Jul 6, 2004, 12:15 PM
Given all that, yes of course there is also SOME difference between AAC/MP4 compression and lossless compression--that's why Apple Lossless exists. But can you really hear it when testing blind?
Or more to the point, can you reliably tell which is which and do you always prefer the uncompressed version? Most people (other than those that are completely tone-deaf) can tell that there is a difference. But I know of very few that can categorically say which sounds "better" or know which is uncompressed. I know some people that think the compressed audio sounds better (they obviously don't care much for the kinds of sounds that the codec is dropping :) )
I do dislike the "idea" of compression, on principle. It bugs me, the way getting a JPEG from a client instead of a TIFF bugs me--even if I can't spot any defects. For my favorite groups, I often choose the CD for that vague reason. But generally I can get over the "on principle" discomfort for the sake of fitting more music into less space, downloading it faster, and playing it with less battery drain. Thus, even my CDs are ripped to 128 AAC, and I'm more than happy using my PowerBook as my home stereo.
I completely agree. I would definitely prefer lossless, but my music collection (at 128K AAC) is 34GB. At lossless, it would grow to about 180GB. I would have to start considering the purchase of another 250G drive, and making backups (onto the 33G tapes I use now) would become a nightmare. I can't possibly imagine the difference in sound quality being enough to make me feel that the benefits outweigh the problems.
In closing, one more factor: even if you're the rare person who can tell the difference, that doesn't mean you are hearing a "problem" or a "defect." You'll hear a difference from one speaker to another, one stereo to another, one room to another, one format to another... different frequencies emphasized, etc. You may like one sound better than another. You may like AAC better than the raw CD--I've read that blind tests DO often come out that way! It's largely personal taste--and the difference is utterly swamped by your own setup's variations anyway--things like the equalizer on your stereo.
Heck, the furnature in the room can affect sound quality at least as much as a compression algorithm. Hardwood floors vs. carpeting vs. tiles will have a huge impact. Brick/cement walls vs. sheetrock vs. plaster will affect sound. The presence of wall hangings (paintings, photographs, tapestries, other stuff). Bookshelves and the stuff on them. Windows and curtains. Whether the door is open.

In my own living room, I get a huge change in the sound if my curtains are all closed or if they are all open (exposing a large picture window). If I open the front door, exposing the storm-door, that also has a huge change on the sound.

IMO, if you're not the kind of person who cares how the sound changes when the curtains are opened or closed, you're not going to care about the small changes introduced by a good quality codec like AAC at 128K.

nagromme
Jul 6, 2004, 01:11 PM
Add the direction and positioning of the speakers. I once moved a speaker 6 inches, and somehow, the way things were arranged in the room, the bass was magnified massively. I had to put it back, even though there was nothing right near the speaker in either position, and floor underneath was unchanged.

shamino
Jul 6, 2004, 02:03 PM
Add the direction and positioning of the speakers. I once moved a speaker 6 inches, and somehow, the way things were arranged in the room, the bass was magnified massively. I had to put it back, even though there was nothing right near the speaker in either position, and floor underneath was unchanged.
Sounds like standing waves. Sound reflects off of a smooth surface at just the right distance from the speaker so that the reflection is in-phase with sound coming off of the speaker. The constructive interference amplifies the sound. Sound-absorbant materials (curtains, tapestries, carpeting, accoustic tile, etc.) in the right place on the surface in question will dampen the reflection and eliminate the effect.

The hard part is finding the surface in question and figuring out what to put there that will dampen the reflection and still look good in the room.

Changing the shape/texture of the surface also works, but that's a much bigger job than just hanging a curtain or putting down a throw-rug.

Or you can just move the speaker back where it was :)

nagromme
Jul 6, 2004, 02:10 PM
Actually, I moved to a new city entirely :)

It was weird because the speaker was on carpet, about 2.5 feet out from an empty corner, both walls had floor-to-ceiling cloth tapestries, and the nearest furniture was textured fabric too. No openings in the back of the speaker facing the corner, either. All I did was move the speaker back to 1.5 feet from the corner so it was more out of the way. I'd expect that even a fabric-covered corner would have SOME effect. Just not the magnitude it did. Things were just right I guess! I don't play music loud, but after that, I started the music again and had to run for the Mute because the neighbor's wall was shaking...

yamabushi
Jul 7, 2004, 07:10 AM
Why not just buy the CDs in stores for the same $12-13 and eliminate the middleman? :rolleyes:
That certainly wouldn't help Apple at all. It is also an inconvenience for the consumer.

yamabushi
Jul 11, 2004, 06:36 AM
After some consideration, I have changed my mind about the bit rate. Since there are some songs that sound poor at 128Kb AAC perhaps Apple should bump up the default bit rate just a smidge in the future. Perhaps 160Kb would be good enough. Certain songs in the iTMS library could have a higher priority to receive the upgrade. Many songs could stay at 128Kb if the perceived increase in quality would not be very noticeable for that particular song.

If Apple were to increase the capacity of the next generation of iPods by about 25% then they could increase the bit rate by about 25% and maintain approximately the same song capacity with improved quality. Actually some of the iPods will probably increase capacity more than 25% so both song capacity and quality would increase for those models. This would provide Apple with improved selling points for both iTMS and iPods - quality and capacity.