Sunday, September 04, 2005

Archiving & Comparing: A Quick Look At Ogg Vorbis

I have finally gotten around to archiving our CD collection to HDD. Last night I ripped about a third of our discs to Ogg with CDex1. At some point in the process I noticed that the codec dlls being utilized by CDex 1.5.1 were about three years old. I wondered what I was missing in quality & performance by not employing newer versions of the Ogg codecs. Long story short(er), you can find drop in replacements of the dll files for CDex at the following location:

You might as well take a look around the Rarewares Ogg page while your at it, there might be something else of interest there for you.

Anyway, unzip the into your CDex directory and you are ready to go. (I copied the old dlls into another directory just in case I wanted to go back to them for reference or otherwise...)

Honestly, on initial testing I cannot hear a difference between the old and new versions (encoded with the same settings in CDex). However, I can definitely see some differences in the output when I look at the waveforms in Audacity. I am going to take a guess here and say, the newer version of the codec probably does a better job preserving the audio quality of the original. You think?

A Totally Unscientific Encoding Format Comparison

The sample used is from Tom Petty, Full Moon Fever, Running Down A Dream (1989)


Ogg Old

Ogg New


Image Legend











Xiph.Org libVorbis I 20020717

Xiph.Org libVorbis I 20050304

Lame MP3 Encoder (v. 1.30, engine 3.92 MMX)

Nominal Bitrate




Avg Bitrate




It looks to me like both the Ogg codecs compare fairly favorably to the original (WAV). The MP3 sample, less so. But to answer the question, which of the Ogg codecs is more accurate in staying true to the original, obviously this little snippet cannot answer that definitively. However, I think it does provide a small window into the overall accuracy picture. As I looked through the one minute sample in Audacity it appeared clear to me that both Ogg codecs samples are superior in staying true to the original over the MP3 encoding (at similar bitrates). This is not news or even surprising of course. What did surprise me however, is the older OGG codec appears to stay truer to the original waveform then the newer version. Hmm...

In the end though, the only thing that really counts is what it sounds like. Music encoded as ~128kbp MP3 files sound terrible to me. The high end is always a wash. Ogg encoded music files at (nominal) 120kbp are quite passable, IMHO with either codec I tried.

Oh how subjective (and probably useless) this all is. :-)

1Why not use *nix for this project you ask? Well, I still have the Linspire & SuSE Audio LiveCD torrents seeding on my Win2K partition and I don't want to reboot my main workstation. CDex in Windows works fine...

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