What size/type of fuse does it take, and is it power cord socket?
Mribob, It's a 15 Amp slow-blo. It's a miniature fuse holder that requires a screw drive to open and close. Mine was loose so the cover spins when taking it off or on. I replaced it with a high quality Bussmann panel fuse holder but accidently bought a larger size. I'm very meticulous so no idea how it happened ... When Hegel tech returned the amp, I thought he installed a different fuse holder so ask and it was mine.
Sometimes things have ways of working out ... turns of SR RED offers a large size 15A Slo-blo but not smaller size.
The $64K question - are no fuses better than Black fuses?
Yes, Reason ARC and CAT use resistors and NOT fuse to protect power tube failures. People always criticizing ARC and CAT but especially ARC so maybe now they understand.