I finished my Clementine 6L6 Ultra about a week ago, and from the first power-on it worked perfectly, with the power transformer never getting more than slightly warm.
On Friday, however, the music suddenly faded and died during a listening session. The 1.5A slow-blow fuse had blown, and the power transformer was noticeably warm (and emitting a solvent or ozone-type smell), but no other components appeared hot or damaged. Further, I checked the entire circuit and no wires or components were improperly installed or shorted to ground, and all resistance specs (including for the components in the power section) are normal.
To help isolate the problem I removed the power transformer from the amp and tested its DC resistance: 2.5 ohms across the primary, around 82 ohms across the main secondary (62 ohms from one red wire to center tap, and 20 ohms from the other red wire to center tap), and around 0.4 ohms across the heater secondary. The differential between the two sides of the main secondary made me suspect something was wrong with the transformer. Then I briefly applied 120V AC, and the transformer immediately started buzzing/arcing, and the solvent/ozone smell returned.
Given the above, I believe the power transformer is defective. What I am struggling to understand is why it functioned normally for about a week before failing. Again, I've thoroughly checked all other aspects of the amp and everything else appears fine. Also, as I noted, the failure occurred suddenly in the middle of a listening session--there was no external physical stimulus, or any visible symptom like smoke, etc.
Has anyone experienced a similar issue? I also plan to contact Edcor on Tuesday to get their thoughts. Thanks.