Did some experiments on the fuse of my amp... I replaced a 500mA 250v
fuse with a 1.6a 125v fuse and found the sound much improved. Then I
decided to replace the 1.6a fuse with a jumper made of a silver
paperclip, and found the sound improved much further. Then I replaced
the paper clip with silver solder, and found it improved further
(though I'm less sure about the solder being better than the clip
overall...).

Question is: Exactly what risks are there in running an integrated amp
or a preamp sans fuse? I don't care so much about the gear blowing up,
since its old gear anyway. But nor do I want a fire started when I
leave the amp running all night or am not at home. In the case of the
preamp, the casing is solid metal, with the integrated, its a wood
casing. What are the chances of fire and how would it start? What are
the chances of it blowing up and how might that occur? (so far, no
problems!). Is electrical shock a risk with a fuseless amp?