How to set up master clock and loop sync in HD3 system

[maximumimpactmedia]

I do have multiple PT systems:

I have PT 8 cs2 with the two 96ios, 2 192ios, and MADI. It also has a Presonus 96k digimax interface with word clock in.

I have a DIGI003 console on a dual boot PC for Da Vinci resolve editing on Win 11 pro since we have a BMD HD8 TV studio video switcher (which accepts MADI) and PT10 on Win 7 with a 192 digital io.

Would you clock these together or just keep these systems separate? If you clock together, how is it done?

[maximumimpactmedia]

Pt automatically made 96 io #1 as the master clock when I changed to internal clock and removed the BLA mk3 as external clock. No need to answer. Thanks

[BScout]

PT always defaults to the first interface for loop sync (unless you have a SyncHD/SyncX in which case that becomes the master.) You have to manually change it to another which is pointless (because it is a loop.)

But it really doesn't matter since loop sync is always 256x base clock speed (that's how many pulses it sends out.) Wordclock is base clock speed up to 4x base clock speed (for 192kHz sessions) It is sample rate dependent unlike loop sync. So loop sync, generally, has more precision

[BScout]

Originally Posted by maximumimpactmedia

Would you clock these together or just keep these systems separate? If you clock together, how is it done?

If the different systems aren't feeding into each other, there is no point to clock them together.

Standalone systems stay separate.

(In post production our systems send digital signal into each other so they have to be clocked together otherwise you get pops/snats)

If you did need to clock something that is sending digital signal into a loop-synced PT system, run a wordclock out from any of the ProTools interfaces to your external device. All the wordclock outs are sending a clocking signal derived from the loop-sync always.

[Darryl Ramm]

^^^ what BScout said, and if I needed a facility wide word clock, (without an Avid Sync HD etc) I would run that via one WC cable into the interface that is the loop master. But only if it was needed for some reason.... thinking the audio might sound better with clock foo magic is not a reason in my book.

If you are buying fancy marketed Canare WC clock cables and looking at running those in fan out style into every interface in a loop you are maybe looking at $50-$100 per cable, plus the cost of the clock box. This seems like a waste of money. If this is not needed you might have been able to purchase a used HD IO for that cost , or just save the money for something you need.

I hope you run setups that are typical and easy to understand for your students. Starting with how loop sync works in a stand alone rig, and how to change clocking say if you have external digital signals coming in. Which might or might not use inbound or outbound WC... all important stuff for a student engineer to learn. I would start that with no external master clocks and no Sync HD boxes, KISS, for the sake of learning. If your students eventually touch video/post then I sure would want them to see a Sync HD box in the stack, but only then.

[JFreak]

^ what Darryl said.

When we had MIX systems before HD systems were launched in 2002, the thing was to have a master clock (Apogee Big Ben was popular) to feed clocking to each interface.

But once HD systems were released, that changed. HD systems need to loop sync the interfaces together. That is rule number one. And by default, loop master is also clock master. And if you NEED to use external clock, you connect that feed to ext.clock input of the loop master.

End of story. It is rather simple once you get the concept.

[maximumimpactmedia]

https://youtu.be/vfOjm6iWzU4?si=A4oocCVonMemBNBd

This video says that you need some HD sync device going into the circular serial clock in port on the card.

Whereas you send master clock to the WordClock in on the loop master.

Please clarify.

[BScout]

Originally Posted by maximumimpactmedia

https://youtu.be/vfOjm6iWzU4?si=A4oocCVonMemBNBd

This video says that you need some HD sync device going into the circular serial clock in port on the card.

Whereas you send master clock to the WordClock in on the loop master.

Please clarify.

You don't.
You don't need a SyncHD or SyncX. And if you use one, you don't need to use a master clock with it. And you don't need either for loop sync.

Hope that clarifies.