Stereo V Joint stereo Again!

[Anonymous5394]

I am well aware of the debate as you probably annoyingly are regarding "joint stereo killing surround signals at bitrates lower than 192kb/s." There was an excellent article here showing that.

https://forum.videohelp.com/threads/80513-Does-joint-stereo-destroy-Dolby-Surround-Sound-(rewritten)

My question then is why do programs like AutoGK, old version of Handbrake etc always mix 128Kb/s to default joint stereo?

Even when I set Lame to stereo in my system(codec pack installed) these programs use their built in own switches from install folder so waste of time there. Unless Im doing it wrongly? No doubt though that Joint stereo does produce good quality stereo. What do you guys think on usage of low bitrate or does 44.1hz 128 stereo give a much better option qualitywise?

An old debate at this Forum below has some saying Lame preserve surround using joint, though no bitrate is mentioned:

http://forum.doom9.org/archive/index.php/t-11042.html

[jagabo]

My question then is why do programs like AutoGK, old version of Handbrake etc always mix 128Kb/s to default joint stereo?

Because 128 Kb stereo MP3 sounds even worse.

[Anonymous5394]

Interesting! I read joint stereo gives the better quality allround using lower bitrate, but would have thought it was more practical to use stereo at lower bitrates to preserve surround signals. A compromise, but I never assumed stereo was worse quality at 128kb/s!

[jagabo]

The idea behind joint stereo is that much of the sound in a stereo track is the same on both channels. So you use part of the bitrate to encode that common data and a little more to encode the differences between the channels. If you encode both channels as separate streams you have only 64 kbps for each channel and some of it will be wasted encoding sounds that are common to both channels. And remember MP3 is based on the peculiarities of human hearing, not matrix encoding of extra channels. So don't expect to get accurate decoding of those extra channels -- especially at low bitrates.

[Anonymous5394]

I see, some also say that intensity stereo(another form of joint stereo) is beneficial for lower bitrates though in itself quite a lossy form. I encoded some mp3's to 112kb/s at 44.1Hz using intensity type(usually done at bitrates of 96kb/s and below) and the results were very good. They sounded much better/sharper than m/s joint stereo: Lame encoded at 112kb/s 48Hz, in tests. I used the Fraunhofer codec.

Magix Audio Cleaning Lab 16 gives you the option to encode at Joint and Intensity stereo. Whether the result incorporates both or just uses the one more suitable to the source after analysis, I do not really know.

http://wiki.hydrogenaudio.org/index.php?title=Intensity_stereo#Intensity_Stereo

That said intensity sounded pretty good to my ears!