• PhiWi
  • New member
  • Offline
  • Registered: 2024-08-26
  • Posts: 3

Topic: External Clock useful with two 12Mics?

Hi friends,

this is the situation:

Room 1:
Two 12Mics connected via Madi (BNC) go to -->

Room 2:
Fireface UFX III via Madi (BNC)

Now, does it make more sense to clock both 12Mics with an external clock (Apoggee Big Ben) or would it be equally good to just use the first 12Mic as Master?
The Fireface UFX III has to be clocked by Madi in this setup. So the question is really, does it make more sense to clock both 12Mics with an external clock or is this unnecessarily.

I know that it usually is best to use an external clock, if you use let's say more than two digital devices. But other factors here are RMEs reliable internal clock and also the Fireface has to be clocked by MADI in this setup. So the external clock could only be applied to both 12Mics.

Thank you!

2 Reply by ramses (edited by ramses 2024-08-26 12:06:34)

  • ramses
  • DAW Mastermind
  • Offline
  • From: UTC+1
  • Registered: 2012-10-14
  • Posts: 13,194

Re: External Clock useful with two 12Mics?

I don't believe that there are any issues connecting even more devices to each other

With RME you have already an excellent FS clock and SteadyClock FS technology removes any potential clock jitter to a high degree. So the clock signal is being refreshed by every SteadyClock FS device in the chain from master over several slaves.

So both devices, UFX III and 12Mic are perfect clock slaves in every environment by SteadyClock FS.

I would optimize the setup by using fiber optic cable, then you have full galvanic isolation between all devices.
And why not making UFX III clock master? Then the main interface gets the clock from the application via the driver
and all slaves can follow the clock of the master. Configure MADI 96k frames if you want to switch between single/double speed.

UFX III------MADI(o)--------------12Mic----------------MADI(o)------------------12Mic
    |                                                                                                              |
    +----------------------------------------<---------------------------------------------+


WC is not needed, clock via MADI input. WC doesn't provide any better clock quality.

See also my blog article about clock synchronization.
https://www.tonstudio-forum.de/blog/ent … ios-en-de/

BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub14
  • PhiWi
  • New member
  • Offline
  • Registered: 2024-08-26
  • Posts: 3

Re: External Clock useful with two 12Mics?

Thanks! Your answer already clarified a lot.

The situation in the studio is a bit more tricky. We just updated the complete recording system including interface, preamps and computer. Before the computer and interface were in the same room as the preamps and now preamps and interface / computer are  separated in different rooms. The issue is that it would be very complicated to add cables between the rooms, so we were forced to find a solution with the wiring that already exists between the two rooms. Unfortunately there only exist one BNC-Cable and several XLR-Cables connecting both rooms.

I could use a optical fiber cable between the two 12Mics (instead of BNC). Would that make sense? I also ask myself, if it would make sene to use a BNC / XLR - Adapter in order to send a WC - signal from the interface via XLR to the other room with both 12mics. Would that make any sense? It would indeed be cool to setup the clock just from the application.

4 Reply by ramses (edited by ramses 2024-08-26 17:43:42)

  • ramses
  • DAW Mastermind
  • Offline
  • From: UTC+1
  • Registered: 2012-10-14
  • Posts: 13,194

Re: External Clock useful with two 12Mics?

Word clock and BNC bring you no benefits.
The best is to use optical fiber between the devices which gives you galvanic isolation on top.

OM4 cables can be bought ready with the correct plugs (SC or LC) as patch cable up to 30 or on request even 50m or longer.

The multimode fiber cables with LC plug have only a small diameter. If you cannot bring it through the hole through the wands as a duplex cable, then open the plastic mounts and make 2 simplex cables out of it, which are even easier to move through a hole.

Clock synchronization via MADI is possible and no issue, see my drawing in my 1st post.

Adding additional LAN cabling to the two 12Mic units provides a significant advantage. This allows you to integrate the 12Mic into RME's remote control application via IP, offering enhanced metering capabilities. When connected over IP, the remote control benefits from greater bandwidth, enabling both peak and RMS metering to be displayed. In contrast, using MIDI over MADI only utilizes free bits in the MADI protocol header, which offers limited bandwidth. As a result, remote control via MIDI over MADI only allows for peak level monitoring, without the ability to display RMS levels.

See: https://forum.rme-audio.de/viewtopic.ph … 94#p212494

You need different OM4 cables and two RME transceivers for the two 12Mics.

PC                                                     LAN                                             LAN
|                                                         |                                                  |
UFX III (cm)---SC------OM4------LC---12Mic (cs)---LC------OM4------LC---12Mic (cs)
       |                                                                                                       |
       +----------SC-------------------------OM4------------------------------LC----+

cm=clock master, cs=clock slave
The two 12Mics get clock from UFX III via MADI.

See pictures of my setup in my blog article here:
https://www.tonstudio-forum.de/blog/ent … iii-en-de/

Its so easy to build it up via MADI.

And here some views of
- MADIface driver settings
- RME connector and
- remote administration via browser.

https://www.dropbox.com/scl/fi/lr51s2khhmf4bkw612v0j/2024-08-26-MADIface-Driver-Settings-clock-synch-via-MADI.jpg?rlkey=91s9t003n3w6jgk3ry0zcw6jd&amp;dl=1

https://www.dropbox.com/scl/fi/j083uvt6cce3xdqvk6h98/2024-08-26-RME-connector-clock-synch-via-MADI.jpg?rlkey=njx3dn9k5417yulehzpairqwy&amp;dl=1

https://www.dropbox.com/scl/fi/u4k9yamobdv9c683fg19v/2024-08-26-12Mic-remote-control-via-browswer.jpg?rlkey=d24ss2zltxlnohkr9e2p3v2ve&amp;dl=1

BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub14
  • PhiWi
  • New member
  • Offline
  • Registered: 2024-08-26
  • Posts: 3

Re: External Clock useful with two 12Mics?

Thanks!

It's really not possible to add a optical fiber cable between the rooms, as the cables are going through a small tunnel in the floor. Rooms are also not next to each other. Therefore we have to stick with one BNC cable for the MADI connection between both rooms.
But I'll try to connect at least both 12Mics with an optical fibre cable instead of BNC.

However, there are actually LAN cables between both rooms and with that we could establish a USB connection. Therefore remote control via browser is possible.

  • ramses
  • DAW Mastermind
  • Offline
  • From: UTC+1
  • Registered: 2012-10-14
  • Posts: 13,194

Re: External Clock useful with two 12Mics?

PhiWi wrote:

Thanks!

However, there are actually LAN cables between both rooms and with that we could establish a USB connection. Therefore remote control via browser is possible.

You want what? Establish an USB connection via LAN cable?
No, you only need to plug the LAN cable (preferably Gigabit) into the primary LAN port of each 12Mic.

BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub14