[mitch stl]

That's the nice thing about this hobby -- to each his own.  I've tried some expensive streamers in my systems and am just as happy with my humble pi. (In fact Bryston and some makers of not-very-inexpensive streamers use Raspberry Pi boards in their products to much acclaim.)

[newzooreview]

Sure thing. I think it's good to try the Pi4 and see how it meshes with the system.

[jpm]

If you're still looking for a solution, a MicroRendu just popped up on USAM

https://www.usaudiomart.com/details/650007432-sonore-microrendu-amp-ifi-ipower/

[Rusty Jefferson]

...Thanks to the suggestion above, I purchased a used Sonore MicroRendu from US AudioMart. It was $275, which is in the price range of the unavailable Allo USB Signature. I will be curious to see how it sounds. I have an Uptone Audio Ultracap power supply on hand, so I should be able to give it very clean power.

Thanks again to everyone for their insight and suggestions.

[GeorgeAb]

I was looking at the Roon Bridge downloads on the Roon website, and as far as I can see they only offer Roon Bridge installations that layer on top of full Windows, Mac, or Linux OS. https://help.roonlabs.com/portal/en/kb/articles/linux-install#Overview

I have used a NUC Rock as a bridge. NUC Rock as server and another NUC Rock as bridge. The second NUC shows up as endpoint. A 7i3 NUC can be had for about the same price as a Pi4 and it provides a spare if anything happens to your server.