1 Topic by christian.haag (edited by christian.haag 2015-10-12 10:11:10)

  • Registered: 2014-12-15
  • Posts: 2

Topic: MADI over ethernet cable

Our larger live room is two floors lower than the control room.

When we use this live room, we let a 30m optical MADI cable run through the hallway. It's done in 5 minutes and way easer than working with a multicore. There is a MadiFace XT in the control room and an Octamic XTC in the live room.

The building we are in is an office building and it is fully equipped with Ethernet cables. There are at least 6 jacks in each room, a central patch bay and everything is Cat 6.

Is it possible to use the existing Ethernet cables to transport MADI?

Making a permanent installation of optical MADI cable would mean quite some effort including drilling holes through the walls. The ethernet cables are already there.

I was thinking of a media coverter like this: http://www.tp-link.us/products/details/ … 210CS.html

Those converters are designed for the opposite: to connect two copper networks over a long distance using optical cable. In theory I see no issues using them the way we need them, except the protocol.

Does that work? Has someone already make experiences with that?

Christian

2 Reply by MC

  • MC
  • MC
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  • From: Germany/Thailand
  • Registered: 2007-04-06
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Re: MADI over ethernet cable

The TP-Link will not work, because MADI is not Ethernet, and this device is active, so does not understand the different input signal. I am not aware of a simple or cost efficient MADI to 'Ethernet' format converter.

Regards
Matthias Carstens
RME

MC's Website

  • Registered: 2014-12-15
  • Posts: 2

Re: MADI over ethernet cable

Thanks Matthias. I believe we will drill...

  • Hugh
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  • Registered: 2007-05-02
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Re: MADI over ethernet cable

Hello c.h.,

If you have two things - electrical madi and a serious engineer working there - for 30m you can implement what we have in a few instances, ethernet magnetics.
If you use a good 100baseT ethernet transformer (you need 125Mbs) along with some experimentation you can have decent madi transmission over cat-x cable.  Electrical madi has a nominal transmission impedance of 75r and cat-x has a characteristic impedance of 100r-110r, but with judicious termination choices we've made it work in an environment like yours where we had no choice but cat-x.  Your engineer will need a scope that can see an eye pattern to determine termination and pcb layout.
We've used the Pulse Electronics H1012NL and we made some pcbs that have the connections on one side to fit into a case.  Version 1 was passive and worked fine once we found the correct terminations, version 2 used cable eqs and variable gain differential cable drivers for longer distances along with PoE to power the drivers on the far end.  Works very well, better than over coax, and we still have galvanic isolation between ends like fiber.

Hugh

  • ckl
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  • Registered: 2016-04-06
  • Posts: 8

Re: MADI over ethernet cable

there is a little box from the company sonible out there which converts MADI (opt., coax, TP)
http://www.sonible.com/en/products/mlmio/

Fireface UCX
MADIface USB
Babyface Pro