OPINION: There’s a story over at CNN this morning about how everyone is seemingly all-of-a-sudden upset with the quality of audio coming from iTunes.
The solution? Apparently, 16-bit audio isn’t good enough, we have to have 24-bit.
Apart from the fact that the majority of the world’s portable audio devices use digital-to-analog conversion (DAC) processes that only support 16-bit audio, changing from 16-bit to 24-bit simply ignores the one huge factor that overrides audio quality.
And that’s compression.
If record companies and online music retailers are serious about improving audio quality, you can’t keep flogging 128Kbps AAC or even 256Kbps MP3 compressed audio.
The beauty of the audio CD is that it offers users uncompressed pulse-coded modulated (PCM) audio. You basically get all of the nuances that were recorded during the actual session of recording – well, at least far more than you do with AAC or MP3 audio.
AAC, MP3 and other “lossy” compression formats use acoustic modelling and throw away anything the codecs decide isn’t necessary in order to get the bitrate down. So in fact, what you’re listening to is only an approximation of the real thing.
The more bitrate AAC and MP3 throw at the audio track, the more accurate it will be but the fact remains that in order to get 1411Kbps PCM stereo audio down to a 256Kbps MP3 track, five out of every six bits of audio data have to be thrown away.
Changing from 16-bit to 24-bit does nothing to fix that.
If Apple, Sony and the rest of the music vendors are serious about audio quality, it’s time to offer lossless audio compression – whether it’s AAC, WMA or even FLAC.
Giving people 24-bit audio when it’s being shoved through lossy compression algorithms is nothing more than a con.
EDIT: But even if Apple does offer lossless compression, should we have to pay a premium for it? If we haven’t go there yet, surely it’s simpler (and most likely cheaper) to just buy the audio CD and rip the thing yourself.
I’d far rather listen to 16-bit uncompressed PCM audio than 24-bit audio flogged through lossy compression.
#1 by Rob B. on February 25, 2011 - 12:40 pm
“The beauty of the audio CD is that it offers users uncompressed pulse-coded modulated (PCM) audio. You basically get all of the nuances that were recorded during the actual session of recording”
Wrong !!!, virtually all music recorded today in a digital format is captured as 24-bit audio. In order to convert it to 16-bit CD audio, it must go through a dithering process, which has the undesired effect of losing a portion of the original program. The ‘loss’ is simply occurring in a different place.
The best solution would be to keep the music in the 24-bit format it was originally recorded in and move to a true lossless encoding format such as BWAV (WAV) or AIFF. I agree, it is time to scrap MP3 etc, but lets go all the way and start distributing music in the same format that it is being recorded in in the first place. So what if the files are much larger, disk space gets cheaper every year and broadband is pretty much ubiquitous. Granted, you wouldn’t be able to cram your entire 5,000 song iTunes library onto your iPod all at once, (admittedly, your storage capacity would be considerably less), but what is there would sound a lot better.
If the industry can take that step, then perhaps they can start working on solving the other major problem with music production today, specifically the lack of any dynamic range in contemporary recordings. This is not a technical issue but rather a human one, everyone wants the ‘hottest’ recording and this put enormous pressure on Producers and Mastering Engineers to put out product at levels as close to 0 dbfs as possible, (maximum digital signal level). We were actually better off in the days of vinyl. It’s ironic that recorded music way back then exhibited more dynamic range than most of what is produced today, and of all the distribution formats ever created, vinyl suffers from having one of the narrowest dynamic ranges available. Compare vinyl’s average dynamic range (softest to loudest sound that could be reproduced) of 65db to the the theoretical range available in today’s 24 bit digital to analog converters, of just over 135db !! I don’t think you can find any parallels in any other technologies, where the quality of the consumer product has declined as much as it has field of recorded music. Speaking as a musician, an audiophile and as your average music consumer, MP3 was the biggest single backwards step ever experienced in the field of recorded music.
#2 by Darren Yates on February 25, 2011 - 3:00 pm
Rob, what I actually said was…
The beauty of the audio CD is that it offers users uncompressed pulse-coded modulated (PCM) audio. You basically get all of the nuances that were recorded during the actual session of recording – well, at least far more than you do with AAC or MP3 audio.
Yes, 24-bit does go through a dithering process to get to 16-bit so some quality is lost – but it’s a drop in the bucket compared to what is lost through lossy compression. But as I alluded to before, it would require all-new hardware to handle 24-bit audio, at least as far as portable gear goes. I’d be surprised if that would be enough of a marketing reason for most people to jump to a new player.
But I agree with you on MP3 – great for hardware makers and the internet, a backward step for the recorded music industry.
#3 by Rafa H on February 25, 2011 - 10:47 pm
I have not the aptitude to your level of knowledge of the music recording industry or hardware, but I have been very fascinated by the points the two of you have raised.
I actually found this as I am in the process of arranging my music collection, and desired to complete some research on the topic so as to maintaining a somewhat duplicate ‘digital’ version on computer.
As with digital devices, so many variations of the same song in different compressed formats, I like only to feed my ears the best.
Everything is becoming virtual these days, I do wonder when will a time come where we can all hear it the way it was made. . . the technology is there, we just need a standard, 1 standard, the way it is!
I agree with both of you, great discussion guys…