Clockworks???? - Gearspace.com
The No.1 Website for Pro Audio
Old 22nd January 2009
Gear Head
johnnywellas's Avatar
🎧 10 years

Hey there.

I'm kinda lost in time on the matter of clocking digital gear. I'm trying to setup a 32 track recording system - 2x16 track 24/96 A/D > 4xAdat Lightpipe Optical (some 80 feet of cable between FOH and the in-house studio > RME HDSPe Raydat - but I no idea on how to clock it.
I've read some stuff and prosoundweb rec forums by Dan Lavry and Bob Katz, saying that using one of the converters word clock, in series, using non-terminated coaxial cable (except for the ends, i think) introduces less jitter than clocking the gear through a master clock (and it's a lot cheaper to do... heh). What twists my mind is whether the cable distance may compromise the synchronicity of the rig.

Also, and I may have misunderstood it, but supposedly ADAT Lightpipe can carry Word Clock. If it does, could I clock the system just using the optical links i mentioned, or would it require an additional link to do so?

So, summing it up:

- Buying a dedicated master clock or daisy chaining from one of the converters? (or using RME RayDAT's clock?)
- Transmitting the clock signal between FOH and studio by optical or BNC cable?
- Are there any not-so-expensive clocks you can reccommend (in case it's justifiable to use one - of course), like Drawmer's M-Clock Lite, for instance?

Old 22nd January 2009
Gear Nut
🎧 10 years
Hi Johnny,

Careful there - you are not accounting for S/MUX. One HDSPe RayDAT does 32 ch (8 per ADAT port) at 48k or 16 ch (4 per ADAT port) at 96k. Also, ADAT lightpipe is only good for about 10m transmission.

You should look at MADI as a solution, seems perfect for your system: 64 channels at 48k or 32 ch at 96k, uses BNC (std. 75 ohm Word Clock) cable for runs less than 100m or MADI fiber for up to 2000m.

This would require an RME ADI-648 to convert ADAT<>MADI at the AD/DA converters, then run to the MADI card in your PC/Mac. Or you can wait for the new RME converters - M16 or M32 (16 or 32 analog ins direct to MADI & ADAT, same configs available for outputs). This would be reasonably cost effective since you only pay for A/D and you don't seem to need D/A.

Regarding clocking, clock is embedded in ADAT (MADI too), so if you are syncing the converters together you can just set the card to sync to input.

Jeff Petersen
📝 Reply

Similar Threads

Thread / Thread Starter Replies / Views Last Post
replies: 2380 views: 410277
Avatar for didier.brest
didier.brest 3 weeks ago
replies: 1 views: 1658
Avatar for mpdonahue
mpdonahue 2nd December 2011
replies: 30 views: 428
Avatar for Aivaras
Aivaras 30th September 2012
replies: 15 views: 5071
Avatar for budweiser
budweiser 20th February 2018
Post Reply

Welcome to the Gearspace Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and Reverb.com listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.

Slide to join now Processing…

Forum Jump
Forum Jump