I recall reading a while back (3-4 years maybe) that the latest (then) iPad blew everything away for DACing. You might try to find some reviews of those iPads (I remember term "audiophile" used). Like other Apple gear, iPads go cheap after the new models come out, and audio is a walk in the park for just about ANY processor, and power is from a battery (DC), and you should be able to bolt it right up to an iTunes library over WiFi, and ...