Wavpack lossy, do I need -j1 or -s1 ?

2003-05-11 08:19:42

Hi,
After readibg many posts, this or this for instance, I find contradictions when it comes to use Wavpack lossy.

What are the right settings ?
some guys say "better use -j1 it imrproves the quality" and
some others "stereo is better if the bitrate is high"...
and what about -s1 ?

I'm using  -b384 -h -s1, is it safe enough ?

thanks for advance.
sincerely,
Nick

Wavpack lossy, do I need -j1 or -s1 ?

Reply #1 – 2003-05-11 20:35:48

Hi,

The question of whether or not to use joint stereo is not an easy one (which is why I changed the default early on). Joint stereo usually produces better results, but when it doesn't the results may be more obvious. At least that's what I thought before, but now I've found a few samples (furious) in which true stereo is obviously worse. If you are patient, you could use the -n option and choose the mode that results in lower noise for a given sample. If you're not so patient you could use joint stereo for most things and use true stereo for material with a lot of stereo separation (i.e. early Beatles). Both modes will generally give good results, especially at 384 kbps. The difference between joint stereo and true stereo in WavPack lossy mode is not nearly as great as it is with MP3 encoding (although I don't know why this should be).

However, I definitely do not recommend noise shaping (-s) unless you are using very high sampling rates (i.e. 96k). I am interested to find out what Den thinks of the this mode, but I definitely find it more "hissy".

I sometimes encode at the minimum bitrate (265 for 16/44) to make comparing the various options easier. At this low bitrate the audible degradation starts to become easier to spot; at 384 I can't ever hear a difference.

Hope this clears it up... 

Wavpack lossy, do I need -j1 or -s1 ?

Reply #2 – 2003-05-19 08:13:46

Back from 2 weeks of holidays without an internet connection, and I'm frantically catching up with a million emails, and countless unread posts on HA!   

I haven't forgotten about checking out the noise shaping David, and will hopefully get a chance to have a play with it late this week.

I certainly concur that in general the joint stereo is worth leaving on. I'm now regularly using joint stereo for 320 kbit lossy with contemporary music (pop/rock), without any problems. I would be surprised if at 384 kbit there were any issues with joint stereo except in some really unusual instances with hard panned left or right speaker samples when listening through headphones at extremely high volumes.

I also agree that if you want to try out the different switches, they are easier to pick at 265 kbits, in case you want to "train" your ears to hear the diffierence.

Den.