What is Dolby supposed to do?

[jujufactory]

I don't get it. In the old days one would encode Dolby to reduce analog hiss. In the digital world there is no analog hiss, so why the hell is Dolby still used? The reason I'm asking is because we are currently looking for a mixing studio for a feature we made. They keep asking us if we want to encode Dolby and I keep asking them what for and I don't seem to have gotten a satisfactory aswer. Does anybody here know why anybody would need Dolby to mix a movie in the digital age? Thank you.

[Herb]

I would imagine they are talking about surround sound i.e. Dolby 5.1 etc.

[fakir_cz]

Today, the "Dolby" doesn't stand for those legendary noise reduction system anymore, especially in the film industry. When they ask you, if you want to encode to Dolby, they mean the Doby SR-D (aka Dolby Digital) digital multichannel audio format, needed when the film is going to printed on a 35 mm copies. The analog Dolby SR LtRt format (which has actually much more to do with noise reduction than the SR-D) is created too during the process and serves as a backup in case the digital data drops out or the film copy is played back in a theater that doesn't have the SR-D reader equipment.

You need (sort of) to encode to Dolby even if you want to make a 5.1 DVD - then it's the Dolby Digital AC-3 multichannel format. There are alternatives - the audio can be encoded for example as a DTS multichannel stream (which I personally find sonically superior to the AC-3), however in most cases the AC-3 stream is also included for compatibility reasons.

I hope I didn't miss your point...

Tom

[jujufactory]

Does that mean Dolby only comes into play for a 5.1 mix? If I do a stereo mix, do I even need to worry about Dolby?

[Whitecat]

Dolby is also in the loudness metering business, which matters most if you're doing post (mainly TV).

'Dialnorm' specs require Dolby measuring hardware or software.

[bernileimbrock]

if You`re doing a feature film for cinema You'll Need a Dolby License To Put your mix to A MOD Disk, or if you`re doing it direct to DVD you can either put uncompressed LPCM Audio Data on the DVD but in Most Cases you Put an AC3 Stream on the DVD Which is also licensed by Dolby

[Whitecat]

Or you can do an LtRt (Dolby Pro Logic II) without the need for a license. This is still a good option if festival distribution is as far as you're going for now. Obviously it has some sonic compromise but it's fully stereo compatible.

[fakir_cz]

Originally Posted by jujufactory

Does that mean Dolby only comes into play for a 5.1 mix? If I do a stereo mix, do I even need to worry about Dolby?

If we are talking about 2-channel stereo for TV/DVD (because the "genuine" cinematic Dolby Stereo is 4-channel L C R S) then no, you don't need to worry about Dolby, apart from loudness metering (as whitecat said), but that's a job for a re-recording mixer anyway.

We could tell you much better what to worry about () if you told us the exact specification of your movie.

Tom

[jujufactory]

The movie is 2 hours long, cut on Premiere CS3. We did the effects and foley in house and are left with a timeline with 30 Wav tracks. Now I have to go to a mixing place to mix this down to something where we can show it at festivals etc. They keep asking us if we want Dolby. I just don't know where Dolby comes into this as all festivals can handle non-film support. The final print will be an HDCAM tape or won't it? So I don't see where Dolby comes into this.

[bernileimbrock]

Dolby E for example but there is really no need for You to do that we only do that for German Television

if you only want to put a stereo Audio mix to A HDCAM there really is no need for any dolby product. Just record it directly to tape

[DaVogi]

Originally Posted by jujufactory

The movie is 2 hours long, cut on Premiere CS3. We did the effects and foley in house and are left with a timeline with 30 Wav tracks. Now I have to go to a mixing place to mix this down to something where we can show it at festivals etc. They keep asking us if we want Dolby. I just don't know where Dolby comes into this as all festivals can handle non-film support. The final print will be an HDCAM tape or won't it? So I don't see where Dolby comes into this.

how the hell should we know what YOU or your production company exactly need?

stereo mix, 5.1 discrete, lt/rt, loudness normalisation, dolby e...

there are hundreds of possibilities and a lot of them include specific dolby encoding methods. nobody means noise reduction in todays post world if he talks about dolby... so please don't blame the mixing stages that they can't give you a clear answer if you don't know the basics of the business you're dealing in.

[sailor]

You need to get a document from the producer that specifically states what the final delivery format has to be. The festival staff (or perhaps the distributor) should have published one. This will specify what kind of tape/disc they will need, what audio format they want, etc. If there's any need for Dolby processing (Dolby Digital encoding, Dolby E encoding, Dolby ProLogic) on the final delivery master, this document will specify it.

Producers and directors frequently don't know the technical specifics of the final deliverables -- and they have their attention on many other things at this time in the process, so it's definitely not the first thing on their mind. So you may have to press them to help you get the info you need. What you don't want is to find out, late in the mix process, that you need to accommodate a set of deliverables that nobody told you about ahead of time.

There's lots of info on Dolby processing for film and TV in the Post Production forum here. As has been mentioned, it's not about the old noise reduction processes, it's digital encoding processes for transmission and playback of multichannel (surround) soundtracks, and new methods for measuring audio levels when mixing. (Dolby also is involved in setting technical standards and acoustic specifications for film mixing theaters, but this doesn't necessarily apply in your case.)

Get that deliverables document, and then at least you'll know what's required. If you need more explanation after that, the staff at the mix place can help you, or people here on the Post forum can help too.

[jujufactory]

Thank you sailor.

[character]

We used to use a superior technology called Dubly.

[Gamelan]

Originally Posted by character

We used to use a superior technology called Dubly.

That's right. How many albums tanked just because they weren't recorded in Dubly? Now it's movies and we're surrounded with Dubly. Times change.

[jujufactory]

Talking about Dubly, by the way, I never have a second cup of coffee at home.