Hi John

A word of caution: the Finisar AOC has worked very well for others, but it was a disaster for me. It could have been a faulty cable, I just discarded it in disgust! I reverted to the trusty HP SFPs and ipolex single mode fibre that I was using before, which are the best fibre link I've yet created among many that I've tried. Some others like the Finisar SFPs that AfterDark sell at a high cost.

Whatever you choose, the optical link really does work to reduce noise and improve audio quality, just approach with caution and be prepared to try different configurations.

Related to this is a tale I recently heard from friend in Belgium who has some very hi-end kit (Grimm MU1 amongst).

I was recanting a story about my experiences of using an ethernet optical bridge.

He was not using one into the MU1.
Another hifi friend of his was saying, you must try it..
He tried. Could not hear any improvement.

He did know the Grimm has Galvanic isolation, they make quite a big thing about it he said.

He contacted Grimm and asked what they use / demo their system very hi-end systems with, what router, router power, lan cable etc?

They said they use a standard router and PSU, and Cat5 standard cable.
That's it.
The MU1 does the rest.
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.
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On the home front the Gustard U18 has galvanic Isolation I understand.

I spent some time switching between a lan cable straight from my router and one that has the optical link in..

With the Gustard U18 in, I could not really hear any difference!
Both sounded absolutely excellent.

Perhaps perception bias was leading me to hear the optic sounding slightly better / comfortable with how it has been the last week or two, I don't know?

With either the Irritating noise (experienced before) was not there.

As control I plumbed the Ultrarendu feeding USB into WaveIO, and it giving SPdif to Najda.
With this setup I could tell the difference and preferred the optic link.

Gustard U18 and Optic Ethernet is doing good things!

One day I might try optic all the way from the main house router to the kit directly .. quite cheap to buy a run of optic cable lead it through the property just to try.
Not impossible to then drill and plumb the cable in physically hidden.

Would still need the secondary router in the music loft for WiFi though.

Perhaps "A bridge too far"😂

I still have a brand new 5m Finisar AOC in a sealed packet.

After my experience with the first one, I have shied away from trying it, but it remains there looking at me and I shall give it a go sometime when I've psych'd myself up for another failure

You're right, and I will.

However, I'm hardly in a hurry as the HP SFPs and ipolex single-mode fibre are doing a superb job.

The Cisco is a cracker: smooth yet detailed and with stunning bass.

With the Finisars and HPs I found the compatibles sounded nowhere near as good.

You want an original Cisco SFP-10G-AOC5M (or other length) with the logo on one of the SFPs.

Initially I had a 1mt Finisar AOC Cisco compatible. I liked the outcome. Then I ordered a genuine Cisco 1mt AOC as suggested above. It was noticeably better than the compatible. Does any one have any comments as to why the genuine is better than the compatible? I asked this question on another forum and did not receive a response. I am curious.
John

With both SFPs and AOCs, the compatibles are all about making the specification with nothing to spare at the lowest possible cost.

The branded products are made at a higher quality and sell at a premium price.

I doubt that either Finisar or Cisco are even aware of, let alone give a rat's arse about, the tiny number selling into audio applications. For us it's pot luck as to which products work best. So far, for me, the genuine HP, Finisar and Cisco products sound the best.