I contacted Gary,the owner of Electric Avenue,and had many,many questions for him,as I am new to head-fi,and using headphones . He guided me through all I should need to know,and answered all my questions promptly.  One of the forum members suggested I get the Fiio e-10,which I did,,as it also has a dac feature,and a bass switch.....I still use it occasionally,when I/m listening to the internet radio.   The  main amp though, is the PA2v2..it just seems to have a sound quality ,that is a little warmer,and stronger. If anyone is considering a...