I started using the WiiM Amp USB out for all my home office listening about six weeks ago.
In the home office (a small room with hardwood floors and a high ceiling) I use a Fosi Audio DS2 DAC connected with coaxial cables to an early 1990s Yamaha RX-385 receiver (45W per channel). The Fosi S2 sounds great and came out near the top of DACs tested on Audio Science Review.
The Yamaha Bass/Treble/Loudness controls are not used. All EQ is done with the WiiM.
I made the switch because:
The Yamaha has more power and I perceive the sound to be warmer.
I can use the Yamaha headphone jack with a wired connection to my Bowers & Wilkins Px7 S2e headphones. This provides a lossless listening experience when I need to use headphones.
The speakers are Polk S4 book-shelf speakers (8 ohm, 91 dB efficiency) from the same time period as the Yamaha. These were always well matched. My subwoofer supports direct wiring to the Yamaha speaker terminals.
In our family room I use a Yamaha RX-V581 home theatre receiver in Direct mode (2.1, no DSP). Fortunately the RX-V581 is an AirPlay 1 device which means lossless streams are supported over AirPlay. However, my WiiM amp does not support Airplay transmission, so I use iOS or iPadOS devices. Unfortunately I EQ with the Yamaha though I much prefer the WiiM EQ system.
