Matrix Audio SI-1 Network Isolator

A recent discussion on the value of network switches by @fire_water  rekindled my curiosity about revisiting optical isolation. As someone who leans toward minimalism, a single-box optical isolator was the prime draw and to see if newer devices offering further improvements over my existing optical isolator. 

For context, my front end is built around 3 chassis Merging Technologies +PLAYER / Merging Technologies +CLOCK / Merging Technologies +POWER which is already extremely low noise, highly resolving, and very “studio honest,” reflecting its roots in professional high-resolution recording and editing. It doesn’t gloss over upstream shortcomings—if anything, it exposes them. As a result, any change ahead of it is easy to evaluate.

To be fair, my existing Telegärtner OPTO BRIDGE 1000M already performs very well—delivering a cleaner background, lower noise, and solid isolation. No complaints there except it is powered by an external LHY linear power supply…extra cables plus more real estate :-) 

So how does the SI-1 compare?

In my system, the SI-1 builds on Opto Bridge foundation with:

• A further reduction in noise floor
• Greater image density and depth
• Improved microdynamics and sense of flow
• A more natural tonal presentation without sacrificing resolution

The biggest difference?
With the Telegärtner, the presentation was clean and relaxed.
With the SI-1, it becomes more organic, fluid, and musically coherent.

My take:
Telegärtner = excellent isolation
SI-1 = isolation plus signal refinement (regeneration) by breaking ground noise and eliminating EMI/RFI riding on Ethernet. 

In a highly resolving system, that extra layer makes a meaningful difference.

Here’s the rub guys, not every system truly benefits from an audiophile Ethernet switch or an overbuilt router. That’s been my experience after introducing optical isolation into the chain. Once I did, even a high-quality switch like the Telegärtner M12 Gold Switch became redundant.

IMHO, optical isolation is essential for any serious streaming setup. The SI-1 doesn’t feel like a tweak, it comes across as a final-stage refinement, allowing your streamer to perform at its full potential and reveal what it’s genuinely capable of.

Here is my signal chain, 

Apple Router →  SI-1 → Streamer (Merging stack) using a pair of FTA Métis LAN cables. 

https://www.matrix-digi.com/product/125/SI-1