Mini Review
It's good.
I received my DO100 a few days and I could instantly tell an improvement in my audio quality. My configuration is optical output from my PC and connecting the DAC into the main power amplifier input of my AVR, bypassing the AVR's DAC & pre-amp. The AVRs DAC is an ancient AK4324. Audio output is 2 channel PCM mode, 48khz, and DPLL1.
This DAC improved the clarity of the audio. The mid bass is more clear, less muddy. So the audio sounds more transparent and less fatiguing. I did A/B tests and it is noticeable.
The only con is it runs warm to the touch. With that said, SMSL is using high quality UCC ¿KMG? 105C caps so they are rated for high temp and the temperature here is only warm to the touch, not blazing hot.
Overall I'm happy with this unit.