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Are iTMS's 128kbps Songs Worth Collecting?
pinchhazard writes "Randall Stross of the New York Times offers his opinion on iTunes Music Store's decision to offer downloads at only 128 kbps, and that decision's potential to affect collectibility of the songs. The article says that Apple makes the claim on its web site that "you'll get the full quality of uncompressed CD audio using about half the storage space."
Rhapsody, which offers encoding at 192 kbps, is compared."
The "Half the size" bit is about Apple Lossless
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Apple's site uses the "you'll get the full quality of uncompressed CD audio using about half the storage space" in reference to the Apple Lossless codec, not the 128 kbps compression in iTMS songs.
Just check out CDs from the Library and rip them with abcde to flac and archive the .flacs on DVD-R (you can fit about 11 "CDs" per DVD), then make .ogg copies or whatever for your devices.
Yes, unquestionably. Actually, the poor overall quality of low-bitrate lossy encoding is what deters me from iTunes et al.
It should be noted that the defects of inferior recordings become increasingly apparent with better playback hardware. Limitations of consumer-grade hardware is a key limiting factor to the widespread adoption of higher quality audio recording formats (both physical media and encoding schemes).
You can redownload any iTunes song, just open up Tools > Check for Purchased Music.
By summer it was all gone...now shesmovedon. --
First of all, "320kbps variable bitrate" isn't a real bitrate. The MP3 spec goes up to 320kbps so you can't have meant "320kbps average bitrate (vbr)" either. I'm guessing you use constant bitrate.
Secondly, who knows- Apple has the originals, and might offer, once bandwidth gets cheaper, downloads of the music you've bought, at lossless quality.
Of course, the original recording and mastering probably risk more quality loss than the difference between a well-done VBR encoding and the original. Lossless downloads are a bit pointless.
RD
There's a vast amount of music out there that was never mastered at 48khz, so if Apple are indeed making all of the compressed files at that rate we'll be hearing the bad effects of sample rate conversion on top of the aac compression.
-- oldthinkers unbellyfeel ingsoc
It's good to see that as dumbed down as this article was, they got the Rhapsody definitions correct.
ITMS uses 128kbps AAC, wrapped with Apple DRM
Real Music Store uses 192kbps AAC, wrapped with Helix/Real DRM
As of a year ago, Rhapsody used 128kbps WMA, which is only streamed to you in a protected format, so that it is only cached and not in a saveable format. I doubt this has changed much.
The underlying idea behind Rhapsody is kinda cool. Think of the entire ITMS minus the exclusives, and then think of that being streamed to you at $10/month. That's basically what you have. It's an awesome service for discovering new music (just like any CD store, who's going to put down a lot of money on music that sucks? Just use the subscription service to give it a try before buying the CD-quality, well, CD).
Of course, the giant and huge drawback of Rhapsody is that you don't to keep any of the music if you cancel your subscription. In this respect, it's a bit like cable TV or the premium movie channels.
A few points:
1. The Nyquist Theorem states the maximum possible encoded frequency in a digitized waveform. It says nothing about how the waveform may or may not suffer aliasing as the frequency approaches half the sample rate. I.e. a rate of 44.1khz is necessary (but may not be sufficient) to encode a 22.05khz tone. I'm not sure this was clear in your reply.
2. "Human ears listen up to about 16kHz." Leaving aside the variance between ears (which is huge- some can hear above 20khz), nigh-subconscious overtones depend on these frequencies. Even if you can't hear these high frequencies alone very well, they do (measurably, and meaningfully) add something to music. Just crop everything above 16khz on a song and listen critically.
3. "A CD delivers audio at 1411.2kbps. The CD audio format was created to conform to what is the best that human ears need." Yes, based on 1980s research. We've come a long way in audio theory, though. Also, all bits are not created equal- I guarantee you that a DVD-A stream compressed into 1411.2kbps would sound better than a CD.
I think my points still stand.
Best,
RD
The difference between 48khz and 44.1khz in the terms of a piano is only 3 notes (black and white). Its amazing that the amount of even musicians don't get this.
The big difference in what 44.1 and the differences between others are that the higher the frequency of the device recording it, the higher the filtering and aliasing can start. If you start the filter slope in the range of human hearing, you WILL hear the difference. While the Nyquest theorem is correct on paper, it isn't quite as correct in practice.
How do you combat this? Buy rather high end components that are all matched from the beginning of the signal path to the end. most consumer level crap isn't. Most prosumer stuff isn't much better. Ignorant motherfuckers that come to my studio generally make two comments if they know anything about gear:
A) I spend way too much on my gear.
B) I should really invest in something modern that can do 96khz (and soon 192khz).
Because of their ignorance of the world, they believe that the fact that I've spent a hell of a lot more for my old skool shit that can do only 48khz, I'm an idiot myself. The fact is, even outputting 44.1khz, my gear sounds better than theirs because it is fully matched components internally and running from synchronized word clocks meaning that the output is far better than the shit they are listening to on their Digishit 192 HD shytstems. I don't even believe in crap like Monster cable, but generally my clients are believers.
But all in all, the only people that can hear the difference are folks that are paid to let their clients think they can hear the difference. I've had these same persons tell me that a dithered 44.1khz stream that I upsized to 192khz sounded a LOT better than the 96khz version that was originally recorded. All because they knew what rate the device was outputting. You are very right about blind tests...generally the blind tests between the bigger companies include a walkman with 44.1 and a fully matched system in 7.2 on 192. I think they purposely select folks that don't know how to do psychoacoustic studies to do these...
Then again, what am I saying.../. truely believes Ogg sounds better than AAC or even MP3. I'd say equivelent to MP3 at the same bit rate, but inferior to AAC. There are some colorization that makes OOG sound different that shouldn't be happening (none of the compressors should color the sound), that might make folks that are use to the sound more likely to accept it. Unfortunately, I still haven't even seen a true unbiased test of this from folks that are average users not coming from any of the camps that have been studied yet. I've done informal tests, but nothing I'd even report on as fact because I know it was informal, even though more formal in application than the last Oog test I heard a few month back that every slashbitch was touting. Idiots...seriously, take a stats class as well as a research methods course before ever attempting to prove you are smarter than the experts...
Whatever your opinions on AAC vs. MP3 vs. Ogg and so on, anybody reading this article should know that Randall Stross has an extreme bias against Steve Jobs. Stross is the author of "Steve Jobs and the Next Big Thing", a historical piece on NeXT Computer. You can't go two pages in that book without running across Stross editorializing (negatively) about Jobs' personality or intelligence. Not very professional for somebody calling himself a "historian".
So, aside from the fact that Stross is a completely non-technical writer, take his views on Apple strategy and products with a grain of salt the size of Gibraltar.
It's Advanced > Check for Purchased Music
and
It only works if you haven't already downloaded that song before (meaning you purchased it and didn't download it). Go ahead and try it, it'll say all the music for that account has been downloaded. I even tried it on my other machine to see if it mean't that all the music that you own is already in your library but nope, still the same message.
Better back up your own files.
Well, if you want to do illegal, at least do it the right way and get Acquisition, Shareaza or the likes.
allofmp3.com songs are *not* legal under European or American terms, just under Russian terms.
This is true mostly if you have very good headphones or are in a very quiet room. If you are in a room with other random noises, cars passing, people chattering, yourself typing, it probably matters less. Even so, you start to suffer the waterfall effect. You stop listening for the waterfall, but for the sound you want to hear.
And by using records or tapes, you invited using a technology that would and did go away.. well.. not totally.. but you get the gist. you hav eto jump in sometime.
You do make backups of your data, right?
CDs are bulky. Hard drives are not so much. Copying from one hd to another every now and then is NOT that hard. 2 hd's takes up less space than 6 cd's in their jewels. They take up less space than maybe 20 cds out of them.
Which you read once. I'm not buying the cover art, i'm buying the music.
Tell me. Can you, in isolation, take a cd, dvd, 8 track, and decode the information by hand? No? If you don't like AAC, use MP3, it's a solved problem that has opensource versions out there.
The worth of something is dependent on the individual. No one is forcing YOU to like mp3 or aac. Thus, you probably see mp3's and the likes as low worth, while myself, have really high worth for them. I can mix and match months of music via a few keyboard commands. I don't need a bulky juke box to try and do as good as a job as itunes or other software, with 200 cd's.
Your opinions are sound. You don't seem ignorant to the facts. The only thing that's wrong is pushing them on everyone else.
-
ping -f 255.255.255.255 # if only
1. The Nyquist Theorem states the maximum possible encoded frequency in a digitized waveform. It says nothing about how the waveform may or may not suffer aliasing as the frequency approaches half the sample rate. I.e. a rate of 44.1khz is necessary (but may not be sufficient) to encode a 22.05khz tone. I'm not sure this was clear in your reply.
Sorry, this is simply not true. The Nyquist theorem states that you can completely reproduce a band-limited signal if you evenly sample at twice the bandwidth of the signal. If the signal is not band-limited, the content at frequencies above the half-Nyquist rate will be aliased back into the lower frequency spectrum.
A tone, by definition, is a sinusoid and has no higher harmonic content. Therefore, by your example, a 22.05kHz tone (i.e. a sinusoid) can be reproduced with no aliasing by a 44.1kHz sampling rate. However, when your signal is very near the half-Nyquist rate, the phase of the signal becomes important. In practical terms, that is why you usually slightly over-sample your band-limited signal if phase information (i.e. exact reproduction of the signal) is important. For CD audio, the goal was to accurately reproduce 20kHz signals, therefore, the slight oversampling to 44.1kHz (Note: low-pass filter responses also contributed to the need to slightly oversample).
Bottom line, the aliasing in your example comes about because you are not talking about a band-limited signal since you have a non-sinusoidal waveform with its fundamental at 22.05kHz but higher harmonic content at integer multiples of 22.05kHz.
No, it's a slightly different story. AAC beats MP3 in listening tests, but only by a little bit. (And Ogg Vorbis beats AAC, again by a little bit).
Being the skeptical type, when iTMS was launched, and having not been impressed w/ 128k mp3s I did my own quick A/B test of 128k AAC / AIFF from the CD. First, Rip a song (preferably one w/ a significant dynamic range to 128k AAC in itunes. Then select the song and choose "Show song file" from the file menu. Right/Control click (thats either right -or- control, yes, you _can_ use a multi-button mouse w/ a mac.) and choose "Open With" then select Quicktime Player from the submenu that appears. Open the song track from the CD in a similar manner. Now you have the original and your 128k AAC both open in QT Player. Then select "Play all Movies" from the Movie menu. both will start simultaneously. Now you can option-tab to switch between which as focus (and thus which is heard) and do a real-time AB test. It put me at ease. Once you have your hand in place you can close your eyes and randomly switch back and forth a bit to loose track, then try to guess which you're listening to.
MSRP - Tax, Title & Licence Extra Your Milage May Vary
I'm more than happy with 128kbps AAC encoded rips of my CDs
You are aware, are you not, that in blind listening tests AAC 128Kbps now lags behind Vorbis and MPC?
Da Blog
You don't get transparancy with any codec at 128 kbps. Not even AAC! Most people can hear the difference, perhaps not with all music but definetely with some.
It's not a /. contributor that really misleads, but the column (and Stross, it's author) itself.
Well, the grandparent is half right. Apple encodes from whatever the original recording was encoded at. However, the AAC files themselves are encoded in 44.1kHz regardless of what the original encoding was. So it all depends on the difference between standard Red Book encoding and Apple's encoding, to see which one sounds better during any downsampling that may occur in the process.
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Downloading the actual songs (for me) gets about 50KB/s, but you can have multiple transfers at that rate at the same time. I got up to 16 connections when I was at college, which meant I got an album of 192 Ogg in about 3 minutes. YMMV.
Karma: Contrapositive
The scary thing is that to the uninitiated you will sound like you know what you are talking about even though you haven't the slightest clue.
First you say that 320 kbps is lossless because the waveform is "pretty much the same". Then you demonstrate your extreme ignorance of the very process you try to sound knowledgeable about by implying that all 256 kbps compression does is filter frequencies above 20Khz. This is wrong. Completely wrong. Not even close to how it works.
Your assertions about what people can hear or not hear are just that: assertions. It's totally meaningless. Just because audiophiles have not bothered to produce some kind of test to your satisfaction that proves beyond any doubt whatsoever that they can hear the difference does not mean that they cannot hear the difference.
I have done so called abx testing of my own using the software from hydrogenaudio, and I was not only able to correctly distinguish which tracks were compressed, but also which tracks were encoded with which codec (although not as accurately).
I am confident that I could personally pass any legitimate test you could come up with comparing 256 kbps material with the CDs. I will admit that 320 kbps would be more difficult, but given a sufficient amount of time and high enough quality source material, I could blindly identify those as well. So much for your 320 kbps is lossless theory.
There is one codec that I am not completely confident I can identify though: MPC. At a high vbr this codec tends to sound really good, even to me. The author of that proggy really did his homework when it came to psycho-acoustic compression. I haven't done a lot of testing with it. Maybe it really is transparent. I don't know.
I am poor and I can assure you that I do not buy CDs out of the goodness of my heart or because I feel sorry for the rich record company executives and "artists". I buy CDs because I can hear a very significant (varies based on source quality and bitrate) difference.
Quite an experience to live in fear, isn't it? That's what it is to be a slave.
You don't want to be hooking the headphone socket of your iPod to your stereo. Use the dock instead, which has a real line-level output.
There's no short answer, unfortunately. But, if there was, it would be "yes". Why? Because the microfone membrane has mass and it has elasticity. It doesn't matter if it's a "dynamic" (that is, voice-coil type) or piezoelectric or electrostatic or electret or ribbon type. If you do the math, you'll find that mass is the mechanical equivalent of an electric capacitance and elasticity is the mechanical equivalent of an electric indutance. Therefore, the simple fact that every microphone has some kind of membrane to detect the vibrations in the air creates a low-pass filter. The same is true for your eardrum. Small children, even young adults up to 25 or so, may be able to hear some very loud sounds at 20 kHz. I know because I tested it myself when I was 17, I could hear up to 22 kHz, if it was loud enough.
I have never seen any specs for a studio mic rated at 20 kHz. Usually, voice mics start falling at 12 kHz, max. Well, maybe they will print a spectrum up to 20 kHz, but if you look closer you'll see it's at least 10 dB down at that frequqncy.
Here's a CNET article about the closing: http://news.com.com/2100-1017-991480.html.
The official date now is October 14th. They originally wanted to close it July 13th, but a lot of Half.com sellers complained about their plans for selling textbooks on the site before it shut down, so eBay switched the date to October 14th. On that date, Half.com will no longer exist and sales will be done using eBay's auction format or by eBay Stores for those sellers who can justify the cost.
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That experiment has already been debunked. They used faulty equipment that generated harmonics in the audiable range. It's even clear from some of their own graphs.
"as we obviously were with LPs and cassettes since they had infinite information storage capabilities" Ah, so that's why everyone still backs up to tape. Come on, do you seriously believe that an LP or a tape has an infinite information storage capability? Perhaps in a theoretical sense, positing an ideal world free of noise and vibration and with records made out of some perfect continuum substance. But in the real world your signal is limited by noise, both in recording and playback. You can't record or hear any detail finer than the random jiggling of the needle due to heat, trucks outside, earthquakes in China, not to mention electrical noise in the recording circuit. Even if you could eliminate all that (e.g. do it all at absolute zero in orbit around the earth), you'll come down against the granularity of matter which will dictate the maximum smoothness of the groove. And you'd still need to find a perfectly stable electrical source to drive the turntable at constant speed. Put against this the impossibiliyu of losslessly compressing an analogue signal and you'll find that a DVD has far more effective storage capacity of an LP. After all, if vinyl is such a high-density storage medium, where are the vinyl videodiscs with 6-track sound?
The author of this post asserts his moral rights.
Expensive studio mics reproduce the full range 20-20,000 Hz and leave it to the sound engineer to filter out high frequencies if necessary. Here's a real studio mic, a Neumann U89, -4 dB at 20 kHz (see PDFs under "Documents"). Good for about $3000. Or, an order of magnitude cheaper, Audio-Technica AT853a.
I sometimes use the latter type for making live recordings of chorus performances on minidisc and apparently, the white-noise background also extends to 20 kHz. It seems that the Atrac-compression (350 kbit/sec) has a hard time with the noise because you don't need golden ears to hear the compression artifacts.
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This article was published not in the arts section but in the new "SundayBusiness" section.
What's new about it, you say? Well, it recently was re-christened (from "Money & Business") and given a new editor from Fortune magazine, with the intention of expanding its influence and audience.
There's a definite new voice and ideological bias in the section -- something very much more "Wall Street Journal" than "New York Times". If you see the entire section, you'll see that bias in other articles, like a pro-Halliburton article they published a few weeks ago or an anti-Kerry article in this week's "SundayBusiness" as well.
My feeling is that the entire section should be avoided on Sundays; it seems especially corrupt now.
Certainly Real has paid someone for that article.