There is a positive review at https://audiophilestyle.com/blogs/entry/812-ecdesigns-powerdac-r-preview/ .The reviewer covers use with headphones. Also a followup at https://audiophilestyle.com/blogs/entry/815-ecdesigns-powerdac-r-wrap-up/ If you go to ECdesigns' website and download the user...

Today received my Mjolnir-modified STAX 006t and began listening to my new Pollinators with it. Very impressed -- I especially like the improvement in orchestral passages where you can hear clear, detailed lines and instruments, rather than an indistinct muddle.