Which is th optimum bitrate for vorbis 5.1 ch audio?

[NeD tHe OnE]

I want to convert AC3 6CH Audio 448 kbps to ... ogg vorbis 6ch audio @ low bitrate say around 200 or less.. what should i do?

thx

[Blue_MiSfit]

vorbis isn't a very good choice for multichannel. It's great for 2ch or mono, but AAC is much more suited to 5.1. I can usually get a 2:1 reduction compared to the AC3 and have it sound great.

[NeD tHe OnE]

I know that ..

AAC has channel coupling support... so it has advantage over vorbis @ 5.1 audio ..

But my question is . I WANT to convert to OGG VORBIS 6CH ONLY . So which bitrate should I use??

[check]

I'm not sure what your question is. You've been here long enough to know you can't ask about the 'best' (which you seem to be asking about), and you have said you don't want to go above 200kbits. The obvious answer is simply 'try yourself'. Out of interest, what encoder & decoder pair do you use and why do you want multichannel vorbis?
As blue said, vorbis is NOT good for encoding to multichannel audio with, because there are big problems decoding it as 5.1, let alone decoding with the correct channel mapping and so on.

[NeD tHe OnE]

hahaha...

No more of the "best" questions..

well .. i converted ac3 6ch 448 kbps file to ogg vorbis 6ch .. nominal bitrate 156 kbps.. which encoded to 127 kbps original bitratev ... an the same to aac 6ch .. which gave 157 kbps..

AAC sounded better than vorbis .. but it was more like stereo .. not much surround effect..

but vorbis decoded by core vorbis sounded cool . but but lower quality .. anway i can improve the quality with vorbis???

[NeD tHe OnE]

Listen i dony have any problem with decoding ... All i want is more information about encoding multi channel vorbis . And @ 220 kbps 6ch ofcourse .. I've got presumably the same quality as original Ac3 .. but i am asking for around 150 - 180 kbits...

thx

[gameplaya15143]

You will be lucky to if you can even stay below 200kbps at -q -1 @48khz 6ch.

From what you said before, it sounds like you are downmixing to 2ch (surround2 or something). :confused:

[Zero1]

I've barely ever work with Vorbis, but bearing in mind that people say the channel coupling sucks, I would work on 40kbps per channel, or something in that region.

Only way you will improve the quality is increasing the bitrate.

Why is it so important you use Vorbis? It's lower quality at a given bitrate, and correct me if I'm wrong, but it's not like there are any hardware player supporting 6ch Vorbis?