Carlsbad2, I used a slug. Next time it will be a jumper, maybe silver. The funny thing is that although their were immediate changes, they were subtle. What really shocked me was that after about two weeks of heavy play, all of a sudden my bass increased pretty dramatically. I didn't purchase fuses because each of my NAD 2600 amps took 6. The cost of the fuses would have exceeded the cost of the unit!
I am now running a Lumin T2 streamer with a Master fuse and a McIntosh 12000 integrated with a purple fuse. The Master fuse in the Lumin really helped the soundstage expand. The purple.... not so sure.