Hi all,
I am looking into an Ethernet-Fibre optic-Ethernet conversion system with my T1 currently configured as a Roon endpoint. I’ve been looking at the following equipment on Amazon;
https://www.amazon.ca/Ethernet-Converter-SFP-Transceiver-Included/dp/B06XPZ3XQK?th=1
I am by no means an IT guy but I’m hoping that this simple system could provide some of the noise/galvanic isolation benefits without breaking the bank cost wise. Will this system work? And is it worth the trouble? All assistance is appreciated as always.
John S
Yep, I've got just this setup, and started as you did, with consumer-level FMCs. It works pretty well, and as you surmise, it provides a very notable reduction in the noise floor due to lowering susceptibility and impact from RFI/EMI getting onto copper Ethernet, and...just as notably, it also prevents the passage of
low- and high-impedance AC leakage currents (more on this below) but there are other solutions available now that provide even better performance.
The most important factor for any digital-to-digital link is the 1) the quality of the clocks in these devices and 2) the quality of the power supplies powering these devices. The key here is to reduce impact from RFI/EMI and prevent the passage of
low- and high-impedance AC leakage currents. The latter is particularly important because it has an impact on jitter and...significantly,
clock phase noise. Clock phase noise is insidious in digital music file streaming because it impacts
timing, and
timing is critcal for music reproduction.
While the Gigafoil is a good product, its kinda pricey. What I've done instead is get the Sonore OpticalModule (OM) fiber media convertor for $249; less than half the cost of the GigaFoil.
https://www.sonore.us/opticalModule.html
This has a significantly better set of clocks than the el cheapo TP-link or Gtek FMCs I originally started out with and you referenced, as well a high-quality RJ45 jack for the copper Ethernet end. As I've found out with all of this,
everything makes a difference, and this includes the quality of the SFPs used. Even the type, number and wiring of the isolation transformers in the RJ45 jacks and the PHY chip in the convertor makes a difference. The OM also has a significantly better clock than these cheap consumer-grade FMCs.
The Sonore uses a high-quality SFP-style optical transceiver and it takes OM-1 specification LC/LC style optical fiber. I've bought Tripp-Lite OM-1 spec LC/LC fiber for my setup. It is also considerably less expeensive than the GigaFoil.
Sonore has done a very good job of defining an optical system specification for use in high-end audio with their SystemOptique specification.
https://www.sonore.us/systemoptique.html
The other key part of the setup is to use quality linear power supplies. The Switch-Mode power supplies that are provided with generic FMCs are the worst, because they cause low-impedance and high-impedance AC leakage currents on the DC signal voltage that is the analog signal on your Ethernet cables, and as I've mentioned above, these cause jitter and strongly impact clock phase noise.
My recommendation is to follow this specification for best performance and use the components they recommend. The only difference in my system is I am using a 7M run of Tripp-Lite fiber instead of a 1M run, and I am using a generic FMC at my upstream end.
My current setup is Mac Mini Roon Core >Pace Router which has Ethernet ports>upstream TP-link LC FMC with System Optique certified SFP optical transceiver powered by Jameco Reliapro LPS>TrippLite LC/LC OM-1 fiber to downstream Sonore OM FMC powered by Uptone Audio LPS-1.2 linear power supply. The LPS-1.2 will not pass either low-impedance and high-impedance AC leakage currents and brings a considerable improvement in audio quality.
The other component in the chain that makes a considerable difference is the Ethernet cable, and I've found the Shunyata Ethernet cables to be better than anything else I've evaluated by far. Even the "entry-level" Shunyata Venom Ethernet cable absolutely trounced all the other "audiophile-grade" Ethernet cables I evaluated. The best I've tried and am using are the Shunyata Sigma Ethernet cables, so if you need to use an Ethernet cable, I can recommend these. The common-mode noise filter on these and the Shunyata Alpha really lowers the noise floor from common-mode devices (e.g. your smart phone, tablets, WiFi sources, etc., etc.)
Last but not least, the power cord powering your devices also matters as these can
make a significant impact, and I'm using the new Shunyata Venom 14 Digital power cable to power my Mac Mini, the Meanwell transformer brick for the OM, and the Keces P3 power supply that powers my network bridge. You can see a video of the impact these have on the noise on AC mains here:
https://youtu.be/42hmSXhiblc
