Eric -
Basics of what you are referring to (charged caps) is in Analog Devices MT-0156: "Basic DAC Architectures 2" by Walt Kester
I have no opinion on their sound. Not nearly enough experience, yet.
For the record, some very old DACs, with a new digital front end (USB, clock, processing - spit out to DAC) can be superb. I refer to mine as "franken DACs" for short.