What movie soundtracks look like

[Jon P. Inghram]

If you ever wondered where the sound comes from when you're watching a movie, here ya go.

Starting from the left, there's the DTS time code that is used to syncronize the DTS CD-ROM with the movie. Next is the analog tracks. Then, between the sprocket holes, is the Dolby Digital data. And finally on both edges of the film there's the SDDS track. The picture was taken with a Nikon Coolpix 4300.

[Jammrock]

Did you take that pic yourself at a local cinema?

I never knew all four types of theater sound were on a single reel. Very cool info.

Jammrock

[dZeus]

'only' 3 of the 4

I've once hooked up my DVD player to a beamer that was placed next to the flim projector in a cinema, and it was impossible to interface the digital audio output to the sound system.. they used rs232 connectors from what I remember for the sound or something like that.

[KvHagedorn]

When it was analog surround I think there were actually 5 or 6 discreet tracks you could see.

[Jon P. Inghram]

I took it at home, my brother's a projectionist and has a few scraps of ruined film in a drawer. That one was from the very end of a movie, someone probably left a piece of tape on the tail of the movie when they moved it from another platter and forgot to remove it when they started showing it. When it got to the end of the movie it jammed and this is what happened:

[Jammrock]

Originally posted by dZeus
'only' 3 of the 4

In the US there are only 3 digital surround standards for theaters: DTS, Dolby Digital, and SDDS. At least that I know of, but I haven't seen a lot of movies in the theaters lately.

Jammrock

[DGhost]

mmmmhmmmm. we always liked SDDS the best. the sound processors we had at the theater i used to work at were equiped to handle 6 channel output, but could be upgraded to handle 8 channel with an additional daughter board. the SDDS sound processor does have an RS232 port on it, but it is for tweaking/adjusting settings on it. good stuff. not positive what we used for sound output, but i know it wasn't RS232. far heavier duty.

of course, each of those audio streams requires a different reader on the projector, which then have to be synced so that they output the audio at the same time as the frame hits the screen...

[dZeus]

Originally posted by Jammrock
In the US there are only 3 digital surround standards for theaters: DTS, Dolby Digital, and SDDS. At least that I know of, but I haven't seen a lot of movies in the theaters lately.

Jammrock

DTS sound isn't on the reel, so there's 'only' 3 of the 4 standards mentioned on the reel (still impressive).

[Jammrock]

Yes, but the reel still contains information for DTS.

[Jon P. Inghram]

It's just the DTS time code, all the audio data is on a couple CD-ROM's.

[Jammrock]

But that's still information.