I have been comparing Jitterbug and isilencer for some time . First of all Jitterbug,I think takes more power so is not detected by some mobiles phones and tabs. So isilencer has edge in that sense. After extensive listening, i felt jitterbug makes the sound slightly warmer but does not improve the seperation . Ifi isilencer instantly feels as if vocals have more focus without any addition of noise and soundstage is tighter and well defined as compared to jitterbug or without anything in between. I also use ifi idefender with 5v, 4xAA NiMH batteries ( output at full charge is slightly more than 5v but works ok ) surprisingly using idefender after isilencer feels slightly better instead of using idefender before isilencer, I don't know why. May be isilencer is treating already clean battery power and adding very very small noise to battery power in the process of ANC. I did all listening with very revealing HMS+Hugo 2 combo. In fact using foobar asio with a good usb cable like oyaide pcocc A , A class or S class with isilencer and idefender ( idefender fed by 5v battery pack, no expensive linear supply can better battery power ) is all you need for a great transport. no more uber expensive usb decrapifier/ reclocker are needed, believe me.