I'm looking for a small, portable DAC+Amp that can rival my Headroom Micro stack in sound quality. In particular, I am most interested in equivalent levels of separation and sound stage. The particular sound signature is not as much of a concern (I will be using an EQ on the computer) as long as it is not too out of whack. No tubes, stacks, or bulky power supplies (unless to charge re-chargeable batteries). This will be used from a usb laptop output and will drive Sennheiser IE8's and Denon D7000's.
I already have a Headroom BitHead which, while convenient, is not on the same level as the Micro stack.
Price range is <$500 (used okay).
Thanks in advance.