Take a look at this

Mix magazine. issue: september 1991

Look at what it says starting from page 54 about 70mm CDS and T2 sound mixing

https://www.worldradiohistory.com/Archiv...991-09.pdf

excerpted from the pdf

Gary Rydsrtom commented on the mixing stage

he say

...was mixed in a THX monitoring environment, and no surround sound was laid on the masters. " Surround is what we call magic surround," Summers says. " The out-of- phase component will automatically go to surround. Now when I'm making the 70mm master, we have our 18 channels in the board—music, dialog and effects separate. I take the left-center- right of the music and send that to left-centerright of the 70mm master. But I also teed it into the DS-1. and I bring that up in the console and add it in as a discrete surround. "We were mixing in a discrete, splitsurround 70mm format, -he continues. "and in the monitor mix, I was listening to that magic surround comp( ment. I was hearing the whole time what was going to happen, although none was going clown on tape. It's a little bit complicated, but it worked out real well, and it gave me free tracks on the recorder.

It is a good idea to create a backup copy

>>https://www.worldradiohistory.com/Archive-All-Audio/Mix-Magazine/90s/91/Mix-1991-09.pdf<<

That article is a great find, but what does it prove exactly

I read that as they made a stereo mix with out of phase stuff going to surround, and a discrete mix for 70mm, digital or otherwise, with deliberate things put into those surrounds.

Fascinating stuff!

And underneath all this nerdy tech talk, what is proven exactly? Does it say that the CDS mix and the 70mm 6-track were totally different and thus made separately? Or on the contrary, does it say they both derive from the same work and were then adjusted in separate workflows, analog and digital, to correspond to both formats limitations and capabilities?

(2026-09-03, 05:18 AM)Beber Wrote: And underneath all this nerdy tech talk, what is proven exactly? Does it say that the CDS mix and the 70mm 6-track were totally different and thus made separately? Or on the contrary, does it say they both derive from the same work and were then adjusted in separate workflows, analog and digital, to correspond to both formats limitations and capabilities?

Exactly what we knew already

Which is? Cause we only had assumptions and educated guesses. So which is it? The same 5.1 mix spreaded to 2 workflows: one digital and one analog, resulting in both sounding virtually the same? Or 2 complete different mixes and Rydstrom did his work twice for some reason?

(2026-09-03, 03:35 AM)borisanddoris Wrote: I read that as they made a stereo mix with out of phase stuff going to surround, and a discrete mix for 70mm, digital or otherwise, with deliberate things put into those surrounds.

Fascinating stuff!

Yes, the out of phase technique was very logical, and all the mixes created during the mixing stage (including the CDS 5.1 and 70mm 6-track Spektral Recording i.e. the DVD AC3 mix) were designed to easily manipulate and adapt the three main channels for the surround channels.

The out of phase technique indicates that certain primary sounds were diverted from the front channels to create the rear channels; this confirms that a separate master was produced for 70mm screenings utilizing the similar out of phase technique (with the exception of theatrical CDS) observed in the LFE channel of the Live DVD's AC3 mix. This is a type of downmix process at the mixing stage.

Yeah it's obvious they mixed the film, and doctored the output according to the tech for each medium.

What mix is on the D-VHS?