atdavidThis is just a Class-D amp with an inbuilt dac that can take digital input, these also usually have analog inputs as well if you don’t want to use it’s dac or have a better one.
A class-D amplifier with digital input would be more akin to a power-DAC.
Similar to the Technics SE-R1 (except it doesn’t have spdif input they put it on their pre, they use their own L&R link in from their own digital preamp with dac to the SE-R1, and have A to D and D to A in the pre)
https://www.technics.com/content/products/r1/images/se-r1-img-product2-ex.png
https://www.technics.com/content/products/r1/images/su-r1-img-product2-ex.png
Here are a couple of links explaining all the Classes of amplification.
https://circuitdigest.com/tutorial/classes-of-power-amplifier-explained
https://www.electronics-tutorials.ws/amplifier/amplifier-classes.html
Cheers George