Portable DACs that have a similar sound signature to the Directstream DAC for headphones

I know this is tall order, but after using the DirectStream DAC at home for both my home speakers and through my headphone amp (DROP AAA 789), the work computer audio experience is just not doing it for me. There are so many small form factor, portable, USB DACs to choose from, any recommendations? This will be used strictly for earphones, no over ear headphones for me at work.