[vorbis] Ogg too good?

[John Morton]

On Wednesday 06 March 2002 16:05, Colin Dooley wrote:
> I'm just encoding some files with the latest ogg and it's
> too good. I tried encoding things at q1 just to see what
> happened and I couldn't hear the differencee between the
> ogg and the original files.

I find that I can't tell the difference past 4 a Stereolink 2000,
Marantz SR4000 and either Sennheiser HD270's or B&W 603 s2 speakers.
It's definitely fairly easy to tell the difference between some of the hard 
samples (applause.wav, et.al.) below 3, and definitely in the 0-1 range.
A certain amount of that comes from training, though, just listening to 
samples for particular problems that they're supposed to have until
I could make the distinction. You might not want to actually do that,
however :-)

> Maybe it was the type of music I was encoding or limitations
> in my listening equipment or something but it seems pointless
> to have a scale from one to ten and have most of it unused.

It's a scale from 0.00 to 10.00 as it happens.

> Seriously... this is a real problem. What if I *want* mediocre
> quality, eg. for downloads where I don't want people to have
> the full quality version of a song?

Encode at something less than three. It _will_ sound lacking to people who 
care. Additionally, you can do plenty of quality wrecking to the tune
before you feed it to oggenc, such as downsampling to 22100hz, or applying 
some low and high pass filters.

> Also, I think MP3 people will feel cheated if they never need
> use a higher quality level than two or three.

Why does this matter? If they use 3 and it sounds just as good, they end up 
getting a file that's about 20kbps smaller and still win. 

> So please, please, let's have worse quality. It's psychological
> and maybe silly, but I think q1 should sound a *little* bit bad.

Try 0; it's the "oh hell, we'll just throw away bits" mode, and sounds 
somewhat worse. Also, try listening on better equipment. 

Personally, I use 4.99 so as to hedge my bets - it comes out to ~128kbps, but
it's quite a bit higher than than the threshold of quality that I can detect a
difference for. I use that just in case, 1) my equipment improves later on, 
and becomes more revealing and 2) to reduce the likelihood that I run into an 
anomalous track that doesn't sound right at what I think my current 
transparency threshold is.

John

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