I have a line 6 pod hd 500 which requires cans of 100 ohm impedance or higher . I bought the beyerdynamic Dt 770 pro 250 ohm version . It sounds brilliant . Using an Ibanez Rg guitar > pod hd 500 > Dt 770 = good sound. I then added a headphone amp/dac into the mix which brought out more depth and detail to the sound , especially with effects like delays and pitch shifters , but didn't make the overall distortion sound that much better it just coloured it in my opinion. So...