CP650 CAT 773 upside-down?

[Gordon Lupien]

I received a CP650 and expected to see the CAT 773 and CAT 790 options installed, but all I saw was the CAT 790. I didn't even know that was a valid configuration!?

So, I opened it up and found the CAT 773 board mounted upside-down in its position, obviously not connected. I flipped it over and installed it. Now, it registers as installed.

Any ideas why someone would do this?

[Steve Guttag]

They were making a CP650DC (Digital Cinema only). Odds are to avoid having the Dolby Digital options as well as to not age the card. Those are my guesses.

[Josh Jones]

I did this with the digital crossover card in mine. It keeps the card in the processor, but disables it.

[Gordon Lupien]

The question I have is, what features can you access if all you have installed is the CAT 790. I believe the manual states you need the 773 installed to process EX, unless the main board has SRD capability on some later CP650's? If it's one of those later models, why would it have a CAT 773 in it at all...

Thanks for your comments. It is a cool way to keep the option boards safe and with the unit!

[Tj Hopland]

I'm not looking up the numbers but the original 'EX' board just had one AES input pair which wasn't really used by a typical cinema, I think it was more of a studio thing. If they bought this board it was to get the EX decoding for SRD/EX prints. You did see some processors this way because EX was still possibly a thing you could have wanted especially in your big rooms. In the build up to SW EP1 there were implications that if you didn't have EX you were not going to get it on the break and EX was going to be the next big thing in sound, both turned out to not be true for the most part.

When D cinema came along there was a new version of the board that had the 4xAES that you needed for D cinema. There was also a rare version that was 4 in 4 out aes with the footnote of if that board was installed you got no analog output from the rest of the processor. Note that installing any of these boards moves all the surround outputs to the other connector, the one that also has the AES ins on it. Odyssey made various boards to make using these options easier.

One reason to remove the SRD card if you were D cinema only was that allowed you to re assign more buttons. With it installed it locks many of them into the film formats. Where I ran into running out of buttons was if you added 7.1.

[Leo Enticknap]

Note that installing any of these boards moves all the surround outputs to the other connector, the one that also has the AES ins on it. Odyssey made various boards to make using these options easier.

And that arrangement has given me hours of fun in the past when setting up CP650s to output to Q-Sys in arthouse and college theater setups in which the main audio, alternative content video, and control system is based on a Q-Sys core, but a CP650 is retained purely to process 35mm film audio. If a cat790 card is not present in the CP650, all six of the regular 5.1 channels go out of the DB25 master analog output, with the pinouts indicated in the main instruction manual. But if the cat790 is installed, only the stage channels do: all four surrounds (if the CP650 is configured for EX 7.1) come out of the option I/O jack, with the result that it's necessary to make up two DB25 to Q-Sys 4 x Phoenix breakout cables: one for the stage channels, and the other for the surrounds.

There was also a rare version that was 4 in 4 out aes with the footnote of if that board was installed you got no analog output from the rest of the processor.

That was the cat778. I've only ever encountered one CP650 that had it, which sent AES3 out into a Meyer active speaker processor. I simply diverted it into an AES3 input card in a Q-Sys IOFrame for that install.