growl3rYou could use the 3.5mm stereo output to go into the Darkvoice with an 1/8" to dual RCA cable. However as Chrjz mentioned, that cheap little dock may be a better solution since your E17 output is specifically a headphone out. That dock provides a line out that is more meant to connect to external devices like this. It probably is a fixed volume output since it is meant to connect to another amp, which is good. You would use the same 1/8" to dual RCA cable to go from that dock to this tube amp. You could use this as your interface cable: http://www.monoprice.com/Product?c_id=102&cp_id=10218&cs_id=1021815&p_id=5597&seq=1&format=2