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Sibelius
8th October 2009, 02:45 PM
Hi there,

I'm just ripping some CDs in iTunes 9, and I've noticed that under "custom" settings in the AAC import settings there's a new option: "Use high efficiency encoding".

What is "high efficiency encoding" and should I use it? What does it do?

I would describe myself as "almost-but-not-quite-an-audiophile" ... I usually listen using good quality speakers and headphones, and have started ripping at iTunes Plus quality (256kbps). So sound quality is more important to me than file size.

Any enlightenment would be greatly appreciated!

decryption
8th October 2009, 02:46 PM
Checkit: High-Efficiency Advanced Audio Coding - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/High-Efficiency_Advanced_Audio_Coding)

It's like a more modern/better version of AAC, which is technically, a more modern/better version of MP3. MP3 is ollldddd.

Sibelius
8th October 2009, 03:02 PM
Thanks ... interesting article ... but a bit over my head in parts for a luddite like me!

So it seems that high efficiency AAC encoding is designed for low-bitrate uses, such as streaming. I still would like to know whether it's best for ripping when it comes to high-bitrate uses.

In other words, what sounds better: a track ripped at 256kpbs AAC with the "Use high encoding" checkbox marked, or not marked?

decryption
8th October 2009, 03:13 PM
I don't know to be honest. Best way to find out is to encode the same song twice - once with it ticked, another without and let your ears be the judge :p

~Coxy
8th October 2009, 04:21 PM
HE is generally designed for ultra-low bandwidth uses like you thought. I wouldn't use it when ripping music for normal use, but for something like playing on a phone with limited space and shitty earbuds it could be a good idea. Streaming music over the internet is also a good use for the HE option.

bullrout
8th October 2009, 04:54 PM
So sound quality is more important to me than file size.



Use Apple Lossless and then you donít need to worry about what lossy encoding is best.:)

Sibelius
8th October 2009, 08:25 PM
Use Apple Lossless and then you donít need to worry about what lossy encoding is best.:)

I said that sound quality was MORE important -- I didn't say that file size was NOT important!

I know that Apple Lossless is an option, but if I encoded the 16000 tracks on my iTunes playlist in Apple Lossless then they wouldn't fit onto my hard disk, let alone onto my iPod!

256kbps or 320kbps is a good compromise for me -- with my equipment, I can't hear the difference between that and lossless anyway.

marc
8th October 2009, 08:52 PM
256kbps or 320kbps is a good compromise for me -- with my equipment, I can't hear the difference between that and lossless anyway.
+1

I'm listening on some very nice speakers too.

bullrout
8th October 2009, 08:56 PM
I like lossless because I donít have to worry about re-encoding ever again (or about how good the latest lossy format is).

Sibelius
9th October 2009, 01:39 AM
Here's what may be an answer:

The Wikipedia article cited by Decryption contains a link (http://www.ebu.ch/en/technical/trev/trev_305-moser.pdf) to another article, which contains a diagram (figure 12) which shows that HE-AAC provides much better sound quality for bitrates below 128kbps, but no improvement for bitrates above 128kbps.

So it's not worth using HE encoding when ripping at 128kbps or more.

simonm
19th October 2009, 04:01 PM
iTunes 9 won't let you encode in HE above 80 kbps anyway! Clearly it's designed for things like ripping audio books or ultra-low bandwidth streaming.