Dolby Digital - Mono? (1 Viewer)

[Robert Woods]

I've found some Region 2 discs marked with the official 'Dolby Digital' logo that are absolutely Mono.
When you read Dolby's stuff at www.dolby.com - this is certainly possible.
But at the same time I see all kinds of menus where Dolby Digital is the alternative to Dolby Surround - yet never says it is 5.1. And I've seen Dolby promos that just say 'Dolby Digital' - and one gets a demo of 5.1/6.1
How did this happen? Dolby Digital 'seems' to now mean 5.1/6.1 - yet it also can just as well be describing Mono?
To make things much 'easier' for the consumer - have you people also noticed that you almost need a MAGNIFYING GLASS when looking at the back of a DVD to find out what sound system has been used? What's the deal with keeping it so 'secret?'
It would seem to me that the system for denoting sound should be:
Dolby Digital 1.0
Dolby Digital 2.0
Dolby Digital 5.1
Dolby Digital 6.1EX

 

[Chuck Kent]

I see your point. But "Dolby Digital" is Dolby's name for what they once called AC-3. IOW, the decoding algorithm used to convert full range audio into a compressed digital state. The terms AC-3 or Dolby Digital never meant 5.1, 6.1, 2.0 or any other number of channels.

Most of the region 1 DVD packages I've bought are marked with the number of channels used for the program inside. Unfortunately, the number of channels can often be very tiny and hard to read. (And, as you noted, sometimes it's not marked at all.)

 

[Michael Reuben]

Dolby Digital 6.1EX

Well, to be precise , this should be "Dolby Digital 5.1EX", since the "sixth" channel is not discrete but is merely EXtracted from the two rear channels.
The only current format that should properly be called "6.1" is DTS-ES Discrete. But the equipment manufacturers are so eager to hype their extra channels that they've make "6.1" common misnomers. (Same thing with "7.1", which should only apply to SDDS-8, a format found only in commerical theaters.)
M.