This is an offshoot of the discussion on the thread about Liquorice Pizza, where the topic of playing back 70mm film with a DTS track on non-DTS hardware was discussed, initially from the comment that the hardware currently being used for 70mm DTS playback is ageing (and could be 28 years old now!) and although Datasat still have a page on their site about it, I would imagine the servicing and replacement options are limited these days. And then I was wondering if anyone's ever played Atmos alongside 70mm (which if so I'd love to see!), and how that might be technically possible.
Continuing on from the thread...

Originally posted by Bobby Henderson
Using SMPTE or MIDI time code would only work for NEW film prints. What about all the existing 35mm and 70mm prints with DTS time code? You can't convert time code that has already been written onto film prints. It should be just as easy to update the firmware in a d-cinema processor to be able to understand DTS time code data when it is read off a film print. On release prints DTS time code is the most common kind of time code data out there. There is no good reason to replace it with another standard such as SMPTE or MIDI. The DTS stuff can pretty much be open-sourced at this point.
Apologies, I may have not been clear enough in what I was trying to say. I'm not proposing replacing the timecode on the print - as you say there is no reason to do that. I'm saying you want to convert the signal/data coming out of the DTS timecode reader into a modern and well used timecode format, like SMPTE or MIDI (probably using USB). So it goes DTS Reader ---> Converter Box ---> Computer, and then the computer can read the modern timecode easily, and play back audio to it (using software that's already available). That way you can continue using the existing timecode readers (which are really just an LED and a sensor built round some rollers, so I don't anticipate any hard to fix failures).

As I said, this isn't theoretical, before I got my XD10 I used my computer to play back the audio according to the timecode from the print. It wasn't perfect (only two channels, and occasional audio jitters), but for an afternoon's trial and error, and only using free software, I was pretty pleased.

Now the real trick would be getting a digital projector to sync a DCP to the timecode, which would allow Atmos to be played for a 70mm print. I seem to recall that some of the early 3d systems involved two projectors - I assume that was timecode based?