Hey folks, been haunting a bit on this and similar threads around here... wondering if anybody's put together a reference on how much battery life we're getting using usb out of a phone to a dac/amp? - esp. without using a battery pack? I mean, I know there must be a difference between the e18 and others like the hifimidy android dac, the uha-4 or dzero... but I can't seem to find much in terms of numbers. thx!