Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Joseph D. Macry]

This week's task is to find a way to transmit a single audio channel over multimode optical fiber.

The application is sending one audio channel around a football field (~1500 ft), to feed DSP/amp rack on Visitor's side. Currently this is fed by baluns which send/receive analog over Cat5e. Client wants it replaced with fiber to eliminate chance of lightning-induced voltage spikes into DSP units. (One Nexia SP has already died from this.)

The existing fiber data installation has two spare MM fibers terminated in the data rooms (MDFs) on each side. Alternately (if they don't want us to use these spares), I have a subcontractor who can run new 6-strand through existing underground conduit.

The audio processor output is balanced mono analog line-level audio. I need to convert this to multimode optical fiber, then patch into fiber patch panels, then do the opposite on the other side.

I have seen Extron's FOX TX/RX AV, which does standard video plus stereo audio, but the dealer price is excessive.
I also found VOSCOM-0100FT/R, which is perfect for the application, but not available in US.
Any other ideas for converters?

[Chris Clark]

Before we switched from MM to SM we did exactly this - single channel of balanced audio in one end and out the other. Unfortunately the name of the old MM equipment we used escapes me, maybe FibreOptions? (It was old though, don't know if it is still made anymore) - it was actually set up as a rack-card system, a primary power source and card-holding frame went into a standard rack and would hold/power up to like 10 cards I think. I also can't think of the name of the new SM equipment we're using now (I presume they would make MM equip too)

[TonyWilliams]

I've installed both the Extron and CSI fibrer boxes before. Looking at Markertek's website, there seems to be a 4 channel balanced audio to MM fiber transmitter and receiver that are around $750 each.


- Tony Williams
Sent from my iPhone using Tapatalk

[Philip Roberts]

I've worked with a bunch of different FiberOptions boxes that do Video + Audio over fiber.

It also might be worth checking out Blackmagic SDI <-> Fiber boxes. You would have to use external gear to audio in and out of SDI. Not sure how their Audio to SDI box would respond with out a video input.

Philip

[Mac Kerr]

I've worked with a bunch of different FiberOptions boxes that do Video + Audio over fiber.

It also might be worth checking out Blackmagic SDI <-> Fiber boxes. You would have to use external gear to audio in and out of SDI. Not sure how their Audio to SDI box would respond with out a video input.

Philip

I doubt it would work without video, SDI uses embedded audio. No video means nowhere to embed the audio.

Mac

[Pete Erskine]

If you can send AES digital audio, Riedel makes a simple box designed to do bidirectional aes on separate pairs.
http://www.riedel.net/LinkClick.aspx?link=Downloads%2fData_Sheets%2fRiedel_FBI%2bCIA_EN.pdf&portalid=0&mid=0&language=en-US&forcedownload=true

[Greg Bellotte]

It also might be worth checking out Blackmagic SDI <-> Fiber boxes. You would have to use external gear to audio in and out of SDI. Not sure how their Audio to SDI box would respond with out a video input.

I have many of the BMD Optical Fiber and SDI Audio units. The audio embedding DOES work without a video signal present. HOWEVER, when connecting a video signal the audio mutes for a very brief instant while the system re-clocks.

[Steve Kennedy-Williams]

Talk to Telecast Fiber Systems.

They make The 5142 for their Viper II frames (also available as a throwdown unit) that sends 4 channels of balanced audio and composite video over MM or SM fiber.

http://www.telecast-fiber.com/Portals/42770/docs/viper%20ii%205142.pdf

We have and use an older model of this card.

[Brandon Yenser]

Look into Fiberplex Technologies, www.fiberplex.com.  They have a ton of appliances that put virtually any communication protocol over fiber.

Additionally, they have an [affordable] active wave-division multiplexer, that will essentially turn a single pair of SM fiber into 16 pairs.  It may be much cheaper to use an extra pair instead of having a contractor put in a bunch more fibers.

[David Garbutt]

This week's task is to find a way to transmit a single audio channel over multimode optical fiber.

The application is sending one audio channel around a football field (~1500 ft), to feed DSP/amp rack on Visitor's side. Currently this is fed by baluns which send/receive analog over Cat5e. Client wants it replaced with fiber to eliminate chance of lightning-induced voltage spikes into DSP units. (One Nexia SP has already died from this.)

The existing fiber data installation has two spare MM fibers terminated in the data rooms (MDFs) on each side. Alternately (if they don't want us to use these spares), I have a subcontractor who can run new 6-strand through existing underground conduit.

The audio processor output is balanced mono analog line-level audio. I need to convert this to multimode optical fiber, then patch into fiber patch panels, then do the opposite on the other side.

I have seen Extron's FOX TX/RX AV, which does standard video plus stereo audio, but the dealer price is excessive.
I also found VOSCOM-0100FT/R, which is perfect for the application, but not available in US.
Any other ideas for converters?

I'm late to this discussion and apologize if I'm replying incorrectly. What was the outcome of this project? I've used American Fibertek for something similar and recently purchased a 4 channel bi directional unit from Voscom (China) It arrived in three days and works great.

[ProSoundWeb Community]