My amp has been running for 5 full months now with daily use of 5 or 6 hours. It is truly impressive that the bias does not drift at all for both channels. And not a single unintended pop or other noise coming out ever. The only glitches were the 1.6A fuse (on 220V line) blew twice at switch on during this period. Now replaced with a 2A fuse. With such great sound coming from such simple circuit, the designer is really a master.
Have you got a thermistor in the primary side of the transformer? If not, it may help with the fuse blowing. See Post in thread 'F5m kit' https://www.diyaudio.com/community/threads/f5m-kit.408290/post-7620032.
The power supply boards are Nelson's Bipolar Power Supply. One board and one transformer per channel. The CL-60 & AC Cap PCBs are installed. One per channel. Now looking back, I should have replaced the 4700uF caps that came with the kit with 10000uF. Maybe after I finish the F5T I am working on.
