Dolby vs 5.1, 7.1, 9.1, 3.2, 6.18, 3.32 ...

[Steinberg]

Guys, one more strange question.

Could You give some light for my thoughts?

I think we all use multichanel audio.
So, if it's not necessary to use compression like Dolby, is there any other reasons to use it?
Is it "fashion" to use Dolby? Paying for sign...?

If my client wish to make multichannel audio track for some video presentation,
I make multichannel (5.1) PCM track - full quality, 24bit, 48kHz...
Those file usually is playing with some portable players or laptop,
no cinema, no tv etc, so there is no necessity to make bitrate lower as possible.
I don't want those audio to be cut out some frequencies & lowering quality.

Once again: Dolby only for make files smaller??? Any other reason?

THX

[lfm]

Isn't Dolby just as much a standard protocol - how to fit the channels together in a stream?
Widely supported by players.

Buying a lot on DVD, and they often have audio as stereo track and 3.2.1 - and stereo may be pcm or Dolby stereo. So I don't think bitrate is the foremost reason using Dolby.

But if you got a player on that laptop that support your format - and client ok with that - just do that. It may also not be widely spread if format is awkward - I mean for your protection of this score.

[BertKoor]

What "Dolby" exactly are you talking about? The Dolby Labs created a lot of technology that found it's way into our homes. I suppose you're talking about Dolby Digital aka AC-3? It's the industry standard for DVDs, it works fine, why discuss it?

A client wants a DVD that simply plays on all devices, and should not care how that's done technically. If uncompressed multi-channel PCM also works and you're comfortable with that, then go ahead.

Here's a small section of a Wiki page revealing a bit why AC3 was chosen instead of MPEG Multichannel:

MPEG Multichannel audio was proposed for use in the ATSC digital TV broadcasting standard, but Dolby Digital (aka. AC-3, A/52) was chosen instead. This is a matter of significant controversy, as it has been revealed that the organizations (The Massachusetts Institute of Technology and Zenith Electronics) behind 2 of the 4 voting board members received tens of millions of dollars of compensation from secret deals with Dolby Laboratories in exchange for their votes.

[Compyfox]

I think we all use multichanel audio.

Not over here - at least not for productions (yet).

So, if it's not necessary to use compression like Dolby, is there any other reasons to use it?
Is it "fashion" to use Dolby? Paying for sign...?

Dolby Digital (or AC3, as mentioned) has it's advantages over RAW PCM. Mainly bandwidth on multi channel audio tracks. Which is the very reason why other "standards" like DTS exist - different CODEC, therefore different "limitations" and reduced bandwidth while playback.

If my client wish to make multichannel audio track for some video presentation,
I make multichannel (5.1) PCM track - full quality, 24bit, 48kHz...
Those file usually is playing with some portable players or laptop,
no cinema, no tv etc, so there is no necessity to make bitrate lower as possible.
I don't want those audio to be cut out some frequencies & lowering quality.

If it's working fine (no dropouts due to the high data bandwidth), and you have the right speaker placement - you can get away with it for the cost of lower picture quality. In turn, you don't pay fees for encoding into AC3/DTS.


Wikipedia (again) has some background info on stream bandwidths for both video and audio on DVD.

On the Steinberg boards are a couple of engineers that roam around this area on a daily basis. They might help you more actually. Same with GearSlutz. Barely seen "surround engineers" here on KVR yet.