How to change fuse on the Marshall Studio classic SC20 head?

[Alter]

It's a new amp, power led turns on, so do all tubes, but there's no sound coming out. All guitar and speaker connections testing ok. There are two fuses underneath the mains that seem ok, is this just a storage and are the fuses supposed to go somewhere else? I don't think this model has a second HT fuse so i don't know if it is a fuse problem or not, but i have no experience with these heads, and can't find any videos that show how you actually change the fuses. Anyone knows?


Turns out it wasn't the fuse but a broken preamp tube..!

 

[PelliX]

Just for the record, the spare in the receptable is indeed a spare. That's the mains fuse. The HT fuse (and others) are inside the amp, so you have to pull the chassis. Glad you got it sorted.