Hiface SPDIF galvanic isolated

[Koenjer]

I have an PC with a M2tech Hiface spdif stick.
This connects with my Rotel processor.

I'm reinstalling the 220v supply to my HIFI stack. And I would like to put the PC on a different phase then my processor and amp.

But there is still the spdif connection between the PC and the processor.
I know there is an transformer on the Hiface side and on the rotel side.

I found this quote on a forum:

"Internally the hiFace uses three DCDC converters to power the Cypress USB controller, the dual oscillators, and the SPDIF converter. Unfortunately the ground of the digital output is connected via 1 kOhm to the USB ground instead of being galvanically isolated which is highly preferable on the S/PDIF output. If the digital input on a listener's DAC is not galvanically isolated either then computer's power supply will be connected to the audio system via the 1 kOhm on the digital input ground pin. This is a very good reason to use a MacBook Pro or different laptop running on battery power eliminating the direct connection to a noisy and cheap switching power supply."

This is the input of the rotel:


How can I make a full galvanic isolation?

[abraxalito]

Use a transformer on the SPDIF output. Bear in mind though that 'full galvanic isolation' does not by any stretch of the imagination guarantee immunity from common-mode noise. A transformer with under a pF of coupling capacitance might get jolly close though, such as some of those from Scientific Conversions.