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Does Portable Music Have to be Compressed?
FunkeyMonk writes "The Christian Science monitor has an article discussing the gap between music fans and audiophiles when it comes to portable music. Would you pay a few cents more to have lossless downloads from iTunes and other online music retailers? As a classical musician myself, I choose not to download most of my music, but rather rip it myself in lossless format."
I would personally pay a few cents less to get CD Quality music. Often when I buy CDs they are priced anywhere from 7.99 to 13.99. I think that if you average it out, the CD ends up being about the same price as iTunes, possibly a dollar or two more. But for that extra dollar, you get a physical copy, that's lossless, and doesn't contain any DRM. I try not to buy CDs with copy protection, and even for the few I do, I can still easily rip them, by disabling autorun. The only advantages of iTunes and other music services are, the ability to buy one track, and the ability to have it right away. I don't usually buy music from artists who can't fill up a whole CD with good music, and I'm not that impatient that I can't wait for the CD to arrive from Amazon, or wait until the next time I happen to be in the mall. Sometimes, if I know I won't be in the mall for a while, I'll download the cd in MP3 format and then buy it later. So, I could buy off iTunes, but i'd get music that was of inferior quality, and locked by Apple, which means that I couldn't play it on another MP3 player without degrading the quality even further.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
I disagree with what you say! Proof? NEVER!
I'm sure there is a contrived test out there that shows a difference. The trick is, to encode a track at 64, 96, 128, 160 and 192bkit/sec with the high quality setting in LAME. Then sit in front of your stereo, put a blindfold on and listen to the tracks [and the original] in a random order.
Chances are for 99% of your music you can easily tell 64 through 128 from the CD but can't tell the diff between 160 and 192 and the CD, and chances are most of the remaining 1% are indistinguishable from 192kbit.
Why shouldn't they offer lossless encodings at the same price as compressed encodings? Um, this thing called "bandwidth." You should have to pay a premium for your audiophile stupidity so the rest of us don't have to pay for your ignorance.
Tom
Someday, I'll have a real sig.
I though all digital formats were lossy!?! ;-)
What you say is, indeed, true.
I categorize myself as an "audiophile", but not as one who believes in any of the audio-voodoo out there. I've done blind ABX testing to see how low my threshold is, and it really hurts to admit this - But when a track (Using music I normally listen to) is encoded with LAME, I cant hear the difference between 128kbps MP3 and a FLAC. That threshold is around the -V5 LAME preset with problem samples.
However, I firmly insist that music downloads should not only be provided free of DRM, but also losslessly to avoid codec-lock in. What if mp3 suddenly dies and SRGLC* is the new hot thing on portable players, such as iPod? What am I then to do with all my lossy files? Transcode them and lose quality? Yes, with decreasing storage prices, I hope that we will soon all have lossless audio files on our computers, portable media players and other multimedia storage hardware.
* Some Random Generic Lossy Codec.
And I think this is the main reason we won't see lossless audio downloads for a while. Where are people supposed to store all their music? If you have to burn it all to CD to prevent it from clogging up your hard drive, then you might as well have bought the CD in the first place. People wouldn't buy from iTunes if it meant that they'd have to buy a large hard drive. Between 8 MPixel digital Cameras, and lossless audio, as well as Apple now offering video downloads, most people don't have the room to store lossless audio on their computer. Let alone on their MP3 player.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
Not all sound engineers are as dedicated to the art as you suggest. Okay, sure, if one wants to listen to something recorded in a state-of-the-art lab by consummate lovers of both the music itself and clean audio in general, then one should invest in the right conditions.
From my own collection, I'll take the world premiere recording of Boulez's Repons as an example. It was recorded in the projection space at IRCAM, one of the world's foremost music and acoustics research laboratories, and I only listen to it from the CD on my home stereo system, which isn't the most whizbang, but the best I can afford.
Contrast this with Rush's 2002 album Vapor Trails , a musically strong release which was recorded in poor circumstances and remastered in worse. The clipping that plagues every track in the album has long been criticized by fans (see the Amazon reviews for further info). So, since the guys who engineered the album didn't aim for clear audio, I feel no shame in putting this in 160 kbps Ogg Vorbis and listening to it with merely average headphones on my portable MP3 player.
As has already been said in many places in the discussion, lossless is probably going to be a draw mostly for classical (or, in my case, modern-classical) fans.
Now, if you wish to sell stuff to audiophiles, then players supporting lossless compression are excellent - they will buy it (along with anything you claim, on whatever grounds, will improve the playback quality).
If you however want to bring better music quality to the general population - make them get better headphones.
Overuse of headphones has probably damaged your hearing if you can't tell the difference between 192kb/sec MP3 and the original source. MP3 compression at that bit rate produces demonstrable artifacts, especially in the high frequency range (but that's the first part of your hearing to go bad, so maybe that's why you can't tell). Your "audiophile" firend is probably well on his way to The Land of Eternal Silence, too.
:-)
No, I'm not another consumer with an opinion. I have years of professional experience with audio and was the guy responsible for (among other things) evaluating and specifying compression codecs for one of the downloading jukebox companies (the kind of juke you find in taverns, etc.).
Compressed media is OK for casual listening. I have an iPod for our car and record vinyl to Minidisc; both formats are fine for their intended uses. Just don't kid yourself that there's no difference.
I suppose I should envy people like you since I wouldn't "need" such nice speakers if I was half deef.
If you're going down that avenue, then all analogue audio is compressed by the bandwidth of every component it passes through and then by the bit rate of every A/D / D/A converter it subsequently hits. Add to that the fact that no speakers or ears are perfect, then you've got abstract "compression" in that the musician can only act on what she hears from her instrument/amp and the engineer can only mix in relation to what he hears from his monitors. And of course there are the numerous artefacts introduced by even the best digital signal processors.
Given all of the above, I think it's safe to assume that in most cases "lossless" begins after the CD is pressed (or, if you take the "Loudness War" into consideration, before it hits the mastering house).
There was a time when I couldn't hear a bit difference between a redbook CD track and the same song ripped as an MP3 at 192k. Then I went to school to get my BS in audio production. It is amazing how much more detail you can hear in music when you are trained to do so for four years. I would have never believed for a second that my advisor could hear things in music that I couldn't, until two years later when I 'saw the light'. Over time I began to pick out subtleties in music, even if I was hearing the piece for the first time. All of the high end audio products generally have no benifit for the average consumer, but in a studio setting, when trained ears are listening, that expensive gear tends to be more valued. There is an inherent problem with this situation, though. Is it reason enough to justify buying equipment that is significantly more expensive because my collegues and I find it more pleasing to listen to, while the average consumer of the product can tell no difference? I don't have an answer to this, but I know that there is actually a growing market for DVD audio (with 5.1 mixes as well). On a DVD disk we can store music at such high qualities that it rivals the best master analog tape s out there. The bottome line is that your ears are trainable. Listening to music is a learned process, much like wine tasting. At first pass, you may think is all tastes like sour grapes, but over time, with effort, you will discover flavors you never knew existed. For the record, I have been a part of quite a few 'blind' tests juxtaposing certain audio formats, and I can certainly tell the difference between an mp3 at 192/16 and a redbook track. Step than mp3 up to super high quality vbr, and I have some difficulties, unless the music is of the classical genre. Doug
I put lossless content on my iPod sometimes. The main problem is battery life.
Yeah, lossless content can be compressed, but it's not compressed as well as it would be with lossy compression. So, on my iPod, the hard drive spends a lot more time working when I listen to lossless content. The result is a significantly lowered battery life. Go ahead and test this yourself if you have an iPod, or other drive-based MP3 player.
It's not as bad as it is with completely uncompressed content, but it's a good deal worse than it is with AAC and MP3 content.
IMO, lossless is the right choice for media centers and other applications that are able to draw power externally, and lossy is the right choice for battery-powered playback.
That sounds nice and well, but the fact is that your CD has already been distorted -- down to only two channels, only 44khz, only 16bit.
(if only they used a lossy compression scheme for CDs, instead of just truncating the audio to fit, then the same CDs that you have no could have held the same music but at much higher qualit -- maybe with more channels, or more than 16bit.)
Yes, they are based on psychoacoustic modelling. But I believe that it is mostly a few curves that define the hearing threshold for certain frequencies in the presence of a loud masking tone. The rest is trial and error, with lots of fine-tuning of a zillion parameters in the algorithm while listening to compressed music and asking the golden ears at hydrogenaudio to compare different versions of a codec (at least for the OSS ones). There is no algorithm that will give you the degree of transparency of an encoding as a number that realiably matches the results of double-blind trials.
Regarding generative losses of enoding: masking can for example be done by using the fact that a listener doesn't hear pre-echoes before sharp attacks as long as they don't come earlier than X milliseconds before. The encoder uses this fact to get the bitrate of sharp attacks down. But on the second encoding, the pre-echo might become 2X milliseconds rather than X milliseconds, and be audible.
I've seen reports on hydrogenaudio that codecs such as LAME that use complex psya modelling extensively do a worse job as a source for transcoding than fast high-bitrate codecs that have much simpler algorithms for throwing away information.
I suppose you are talking about transcoding to the same bitrate MP3 with the same psychoacoustic model. That could be useful if you want to get rid of DRM by burning to CD and then re-ripping. But the question is whether transcoding to a lower bitrate or even different codec will give audibly different results from encoding directly from the source.
Avantslash: low-bandwidth mobile slashdot.
A typical MP3 is better than the next most common format--FM radio--but I don't remember hearing people bitching about FM radio for the last few decades.
A better question: are audiophiles *ever* happy? I think the answer is "no." Gamers are never happy with how fast their rigs are, hot rodders want better cars, horny teens want more sex, hippies want more wood chips in their granola, etc etc etc. Basically, most people are never happy with what's most important to them.
And this particular question is as dumb as they come. A 6-GB MP3 player held a certain number of 128k MP3s. A 60 GB player today holds the same number of WAVs or AIFFs. So the answer, OBVIOUSLY, is "Yes, you can carry around perfect CD-quality songs." The only question is how many. Not enough? Wait a couple years.
Next?
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And what's more - almost all records were mastered (two generations!) from analog tape, where the magnetic particles and the tape speed physics interact to give you quantized audio with random thermal noise inserted - in short - a fairly lumpy recording environment that in many cases can not reproduce frequencies anywhere near as well as a redbook audio CD, yet the fanatics seem to assume that the resulting vinyl record has infinite bandwidth. Only the direct recording to record disk avoids tape, (but the direct to disk crowd already knew that).
:)
Having said that - it was fun to dig out some old records and play some of the less scratched ones for my teenagers last year - they were very surprised at how good they sound (and I have a cheap consumer grade turnable). They totally expected records to completely suck!
One of the main problems with the "how many bits and what sampling frequency is good enough" debate is that so many people do not understand the point of a Double Blind AB test,
so they blow $800 on new speaker cables with ceramic floor stands and they are very emotionally motivated to prove that they haven't been suckered. The mind is a very poor scientific instrument.
All of this is slightly off topic - the point is the online market (itunes etc) only sells you lossy compressed audio, converted from redbook CD's, so it's of no interest to someone who prefers the best quality source they can get, be it a plain CD audio, or the newer DVD-Audio and SACD formats.
Storage is no longer an issue, but download bandwidth is the problem.
Bavarian Purity Law of Rice Krispie Squares: Rice Krispies, Marshmallows, Butter, Vanilla.
What you will end up with is some set on N systems, which will be large amounts of noise with small amounts of useful sound in them, which when superimposed with each other AND a filter function produce the original sound and which when taken individually are highly compressable. (The noise is simply there to create fake patterns that we can compress. It won't be random noise, because that doesn't compress, but is noise in the sense that it has no meaning or purpose other than to produce nice mathematical functions. The filter is simply something that's used to extract this deliberately injected deluge, so that the output is valid.)
Is this a valid technique? Well, yes - it's not that unusual to add noise to simplify compression, then subtract the noise afterwards. That's fairly standard. Splitting the data up to simplify the noise is merely a variant on the idea, and is used in plenty of compression methods. Compressing individually seems to be the customary method, but computing power is more than adequate these days to use fancier techniques IF justified. (Since you can encode the decoding method at the start of any track, it should be wholly irrelevant as to what method is used, provided the computing power is there to run it in real-time.)
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Though they cannot hear them they can sense their lack. The US army did testing in the late 1980s and 90s that determined that the range of harmonic overtones up to 90+kHz can be sensed though not directly heard by people. A lack of these can lead to sounds 'feeling' artificial. This is one of the reasons why there was a push to 96kHz (40+ kHz effective playback top frequency) when the DVD-A standard was being devised.
Personally even nearing 40 I can still hear frequencies in the 20kHz+ range and also at the low end of the range as well with a great degree of sensitivity.
Quidquid latine dictum sit, altum viditur
Yes, I know there are other players available, and I know that the iPod supports lossless AIFF and with third-party hacks it can even be made to support stuff like FLAC, but that's a pain in the arse, which is the whole point. Firmware hacks and other players are inconvenient, and MP3 files are conveniently small so I can carry my entire library on the device. I normally compress music to 160kbps, as that's a good trade-off between quality and size. I certainly can't tell the difference between that and uncompressed music when I'm using earphones on the bus.
If I ever want them in a lossless format, I can easily re-rip the files from the original CDs.