Feb 23, 2012
[Edit: Some people have miss-quoted what I'm saying in this video, using it to suggest that the whole idea of "Mastered for iTunes" is bogus. It's not - the full story is far more complicated and interesting than that. For all the details and my latest comments on this topic, click here.]
So, the “Mastered for iTunes” concept has been getting a lot of press in the last couple of days, and there’s a claim that’s being made that bugs me.
Specifically, it’s being said that the “specially Mastered for iTunes” versions, or so-called adaptive mastering, ‘sound closer to the CD’.
Test-ably not true.
Don’t believe me ? Watch the video. It proves this claim is untrue, by using a technique know as ‘null testing’ to highlight the sonic differences.
As I say in the video, people may well prefer the specially “Mastered for iTunes” versions, and there’s absolutely no reason not to make a specific master for a particular release format – but to say that it sounds ‘closer to the CD’ is just wrong.
Let me know what you think in the comments !
Just to be clear, it’s the specific mastering processing that’s supposed to be “optimised for iTunes” that I’m calling out here – the sonic choices made by the mastering engineer.
Apple have release an excellent set of guidelines on Mastering for iTunes, and I’m delighted to see a clear discussion of issues like the loudness wars, sample rate conversion, dither and clipping.
BUT the fact that the new Apple encoders can correctly handle high sample rates, and should make a better job on the conversion, STILL doesn’t mean that the files will sound ‘closer to CD’.
In fact, since at the end of the day we’re still getting a lossy encode, it’s my opinion that the advantages of higher bit-depths and sample rates will be completely outweighed by the AAC encoding.
If Apple really care about giving us high-quality audio, they should offer lossless formats… but that’s a whole other blog post !
A few people have asked me where the claim that “Mastered for iTunes” masters sound “closer to the CD” comes from.
To be clear, this isn’t something that Apple themselves have said, to my knowledge.
The phrase originally came from Scott Hull’s comment on the first post I wrote about Mastering for iTunes, discussing the RHCP release:
September 2, 2011 at 4:14 am:
“The goal of the unique AAC master of the Chili Peppers album was to make it sound as close to the CD as possible. The ears involved in the process felt it was a success. Pick up the CD and compare to the AAC file with your ears. It’s really damn close. Keep in mind, I’m not addressing whether or not you like the sound of the CD. It was RR’s goal to make the Itunes file as true to the sound of the CD as possible despite the data reduction. A lot of time, effort and careful listening went into this project. This was not just media hype.”
And, here’s Rick Rubin saying that AAC encoding needs to be compensated for:
The video in this post was was prompted by the Ars Technica article recently:
- which included quotes like
“The problem? The AAC compression algorithm is “quite quirky.” Without compressing a song, and carefully listening to it, then comparing to the uncompressed master, there’s no way to predict how the sound will change. Vlado Meller, another engineer at Masterdisk, described mastering for iTunes “like polishing your Bentley in total darkness, then turning on the lights to see where you missed.”
“There are no accurate real-time tools to help you hear what the algorithm will do,” VanDette said. “It was not uncommon to revise tracks three, four, even five times until I got something that compared well with the CD.”
Slightly different words, but the same spin. And still not true.
If you found this post interesting, you might like to check out my recent eBook,
“The Essential Production Advice” – it has all the best content from this site site to help you start improving your recording, mixing and production skills today. For more information, click here.