I have a HD650 cable for mine and how big and upgrade it is I don't know as its all I have ever had but for £20 it ain't bad. Then I have one HD600 grille for them but awaiting a second so can't comment on that. They are £12 each. If you wanted spend more the. I'd reccomend a silver cable. Another way would be to improve you Amps as I was just using my Objective 2 and iMac and by adding a Audioengine D1 DAC it's a world of difference.