Sounds like a great idea but I wonder how necessary the refined SQ of dCS would be in practice in a situation such as driving, flying or train travel?
I use an AQ Dragonfly Red which I do not feel much need to improve upon given the environment where it is being used. Listening to e.g Vivaldi ( composer not equipment) on a plane with engine noise and baby screaming throughout. On a train with people sitting down next to me and carrying on a conversation loudly. Driving but where having sound loud enough to drown out both engine noise and that of other traffic involves a hazard risk unless you are only a passenger.
Of course one could go for noise cancelling headphones but then you get into a whole other world of sonic compromise and the advantage or even need for a high quality portable DAC is negated.
So a great idea but maybe only ideal for use in hotel rooms or in a quiet office?