Saturday, September 17, 2005

Hydrogenaudio Forums -> MPC vs VORBIS vs MP3 vs AAC at 180 kbps

I have been playing with music again trying to decide what music encoding is very close to CD quality but still reasonably compressed. I am increasing the sampling rate and thus the compressed size like many people as memory gets cheaper.

I have been doing a bunch of conversions or downloads at MP3 192 kbps VBR which is just above the comparisons in the article sample rate. Ogg Vorbis has a lot to recommend it and I am also considering the Microsoft WMA VBR second best and best quality. The article really likes Ogg Vorbis at around 180 kbps, a highly trained ear could detect no difference in one third of demanding samples. MP3 lame was decent. At a step up in quality I think I wouldn't be able to tell any difference.

All compression formats throw out stuff they don't think matters. The differences are what they throw out and what artifacts they introduce. As you get to the 192 kbps level and above you need a trained ear and good equipment to hear a difference. That is not me or most people.

Here are some approximate sizes of recordings using different formats.

The Song is Green Day - American Idiot.

MP3 LAME VBR 192 kbps (also called standard) 6.70 Megabytes
MP3 LAME CBR 256 kbps 8.94 Mb
MP3 LAME VBR Extreme 7.68 Mb
MP3 LAME CBR Insane 11.17 Mb
WMA9 CBR 2 Pass 192 kbps 6.70 Mb
WMA9 CBR 2 Pass 160 kbps 5.59 Mb
WMA9 VBR Q90 7.33 Mb (Microsoft 2nd best)
WMA9 VBR Q98 11.17 Mb (Microsoft best compressed)
Ogg Vorbis Q6 6.28 Mb
Ogg Vorbis Q7 7.33 Mb
Ogg Vorbis 256 kbps 8.94 Mb
Ogg Vorbis Q9 11.17 Mb
MPEG-4 AAC VBR normal 6.70 Mb
MPEG-4 AAC VBR extreme 7.68 Mb
MPEG-4 AAC VBR audiophile 11.17 Mb
MPC standard 5.59 Mb
MPC xtreme 6.70 Mb
MPC insane 8.38 Mb
-------------------
WMA 9 Lossless 31.42 Mb (Around half the size of original, claims no audible difference.)
PCM Wave 50.27 Mb

I don't know how they get the approximate numbers at the site but I don't think they are very far off.

By the way - this site is the Russian AllofMP3.com and sells the songs at 2 cents per megabyte. That is much less than the 99 cent typical price of US download sites which give you restricted recordings. The first MP3 version list here above would be 13.4 cents. You charge $10.00 and download what you want in the format you want until you need more money. Only a perfect wave copy would be about the same price as it is at most American sites like iTunes.

ITunes generally uses AAC but you can specify the format and quality. Note that both Apple and MicroSoft claim they are much better than mp3 but most of that is marketing and comparisons to older encoders. They are mostly better at working with the RIAA and preventing you from moving music produced or downloaded to their equipment around and/or giving it away.

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