Fiber Optic AOC - Active Optical Cables

Audio Gear Talk
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I see plenty of discussions arounds using fiber in the ‘last mile’ to the Holo Dac via a media converter.

Completely understand the desire for optical isolation in the chain but I’ve always wondered about the latency and overhead of fiber optic: Transceiver > physical optical coupling > fiber > physical optical coupling > Transceiver.
That’s a bunch of work and heat being produced!
It also introduces potential issues about mixing and matching transceivers and optical cable types.

I run 10Gb at home (very affordable now!) and recently converted over to Direct Attached Cables (DAC) for all the SFP connections (fixed length copper cables from SFP to SFP port).
Result: Simplicity, lower latency & lower Bit Error Ratio (BER) and no heat.

The BER ratio is interesting. With optical, something as simple as forgetting to clean the end of the fiber or inadvertantly stepping on the cable could introduce bit errors. The issue I have with BER is that I have no way to test/measure for it. The connection LED is lit @ 1Gb but perhaps throughput is suffering do to some unknown error - I would have no clue if there was a BER problem.

So what about using an Active Optical Cable (AOC)? AOC’s come in fixed lengths with the cable optics actually embedded in the transceiver. They have lower BER error ratios than physical transceiver/optical setups, lower heat, are vastly simpler and still give all the optical isolation.

Sure, I don’t have a bunch of transceivers & cables to play with any more which isn’t as much fun.
But I do assurance that the connection is optimized the first time and there is no second guessing on whether I did it all right.

Would love to hear any experiences out there regarding using DAC or AOC cables with the Holo.

Thanks!

Decent AOC information link: Active Optical Cable (AOC) Explained in Details ! – Fosco Connect

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2 Likes
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Hi @J-in-TO

If you can get AOC products that are:

  • Single mode
  • Grade B connectors
  • Bend Insensitive

than it would be just fine.

As I don’t need 10G or higher, AOC has never been an option for me.

Torben

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The best quality in digital audio delivery you will get, when you remove all this unnecessary devices from your chain. Each of these additional devices introduces a new source for problems that need to be fixed with the next fancy gadget. Remove them all and you will have a lot lesser problems and no decline in sound quality - it is digital data transmission and this simply works, otherwise you would not be able to read this text without problems. And no, audio is not something else, regarding digital transmission, even if some manfuctures want to tell you something else to get your money.

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(previous post deleted in error)

Thanks for the feedback.
I note a previous topic debating single vs multimode fiber :wink:
Also, a note: Both DAC & AOC SFP+ cables support data rates of 1 Gb/s to 10 Gb/s.

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With you on that one - elegant simplicity is often the most performant but often difficult path to follow.
There are cases though where simplicity means using purpose built components. For USB I used a dedicated USB PC Card with a Holo Titanis and love it.