Can’t believe how good these little amps are. I can’t quantify or measure it, but I feel there’s more punch with these. So funny, these little boxes are powering my huge Klipsch Forte 4s
I would rather use the Ultra as the master volume with a remote control rather than having to walk across the room to change the volume on the Vibelink
I'm using the Fosi V3 mono amps with a WiiM Ultra with my Klipsch Forte IV. The V3's have a tight and controlled bass as compared to an older Marantz PM-15 I was using.
So if there is no remote included, then to use an Ultra as the preamp, I would use the analog outputs on the Ultra and use the variable output on the Ultra with the VIbelink volume at max.