Electrical Isolation: Fiber Media Converter vs Copper RJ-45 Transceiver Modules

What exactly is your question and how does it relate to the sound of your system?

Whether a digital signal goes through copper or through fiber, it cares not.  

On 6/1/2019 at 1:08 PM, zelbir said:

Question: Do these transceiver modules offer more, less, or equivalent electrical isolation relative to fiber media converters?  Whatever your answer is...why is that the answer?

I *suspect* its equivalent because the copper/fiber transition is merely happening within the transceiver module instead of the FMC.  But, that is speculation on my part...and have not found anything in my research (so far) that answers the question.

Not recommended for audio, according to @Superdad:

Quote

"What I wrote was correct about RJ45 SFP modules containing an Ethernet PHY, tiny cheap clock, and cheap voltage regs. (Avoid those!)"

On 6/1/2019 at 10:08 AM, zelbir said:

I *suspect* its equivalent because the copper/fiber transition is merely happening within the transceiver module instead of the FMC.

There are not any optical fiber elements contained in the type of RJ45 SFP transceiver module you linked to.  Those simply take the 1000Base-X (fiber mode) SGMII differential pairs—at the back of the SFP cage coming from the switch chip—and run them through a PHY chip to produce the UTP for the transformers and RJ45 jack. But since the signal from the cage does not include a clock and all PHYs require one, those modules also have to have a 25MHz clock—as well as multiple voltage regulators to take the 3.3V feed and supply other voltages to the PHY and clock (usually just a cheap crystal).  It is all far from ideal to have all that stuff crammed into an SFP form factor.  And while Finisar is a quality brand, there are still a lot of compromises to build at low cost.

sorry it is redundant, my post deleted