I have never heard any hiss or EMI from the E17 if it was not reciving power from the USB, but when it does its very easy to notice on the HE-400.
Anyone know how much more or less of HIss and EMI has E17 in direct comparison to E12?
So in order of preferences:
2. arround 1 watt
3. Batt life over 8 hours
4. dosent overheat too much
I have called from one cellphone to another (both less than 50sm away from E12 working on a battery) - no audible effect.
I'm guessing E12 V1 was the one with EMI issues.
E12 pairs really good with HE-400, don't think you can find a cheaper option that will drive them that well.
Edited by BenF - 5/20/13 at 10:31am