My first WZ68 rectifier lasted 2011 to 2015, my second 2015 to 12/2022 and never went out, I just replace preventatively. I have now blow two in less than a year, first lasted about 7 months, and just blew the second after only a couple months (pretty sure it is the rectifier at least, took out the fuse again and don't have another back up right now). Last 2 took out the fuse. Both went after hours of music not at startup.
Any ideas if something may be off I should check? Not much has changed in the last year, but I have been using KT120 power tubes since I first built the amp and did replace those at the same time as the rectifier in 12/2022 because my bias was not holding and figured was time to update (kept the old for backups), so I replaced the outputs and rectifier at the same time. So both the rectifiers that went this year were with the new power tubes (from wpc1896 on eBay). But everything else seems fine, and the bias has been holding well ever since the change. I keep bias about 0.550. Maybe I just got some poor webers from a bad batch last time (both the ones that blew this year from the same order).
Any ideas if something may be off I should check? Not much has changed in the last year, but I have been using KT120 power tubes since I first built the amp and did replace those at the same time as the rectifier in 12/2022 because my bias was not holding and figured was time to update (kept the old for backups), so I replaced the outputs and rectifier at the same time. So both the rectifiers that went this year were with the new power tubes (from wpc1896 on eBay). But everything else seems fine, and the bias has been holding well ever since the change. I keep bias about 0.550. Maybe I just got some poor webers from a bad batch last time (both the ones that blew this year from the same order).
