I will be sitting in with a few friends of mine this weekend and we were holding a little practice at my house. They are mostly a folk trio with a little jazz thrown in...not really my generes, but it is fun to join in at times. I was using my Godin Kingpin II through my '79 Twin (my favorite combination for bright jazzy stuff) and we were really clicking as a group and then blink...fuse blew. I had been playing for about an hour and not pushing it hard at all, but what was really odd is how there was no forewarning at all. No odd smells, no odd sounds, no crackling, nothing...just blink and gone. Sadly, I didn't have another fuse to replace it with (4 amp slo-blo) so I had to switch amps. I'll pick up some new fuses this week, but I have never had a fuse blow on any of amps before without some indication that a problem was developing. I keep my gear well serviced and this Twin was just serviced 6 months ago...although tubes are about 3 years old now. Just driving me a little crazy right now, without that fuse, I can't investigate the cause and I am already dreading the possibility of having to drag it 40 miles away to the tech. Sort of ruined a really good day.