Rectifier tube keeps blowing????

Hello All
I built up the st-120 kit and it ran fine for 3-days then out of the blue it started blowing rectifier tubes. I read the voltage coming into my house and it’s 121.7volts I’ve heard this can blow the tube has anyone had this experience??? Thanks
Michael

How did it blow - just out of the blue listening to it - or did you do a quick turn off/turn on -> blow?

When I first started getting aquainted with my M125's - in the early stages - I'd blow a rectifier/fuse by doing a quick turnoff turn on.

If it is just out of the blue and the tubes are all new - and only been up a few days - I'd re-examine all the wiring.

I'd also be sure to use a SS rectifier to start out with - I'd avoid the Weber WS1 like the plague - the WZ68 I've had good luck with and is the only one I'd use.

I also keep the bias at the lowest settings possible.

Lowest Bias, Turnoff/on only when necessary - and I've had the cheapest glass rectifier tubes last very long and not blow.

I had been listening to music and it just blew. Then I replaced the rectifier and started it up as per instructions and it blew again........

My house voltage is higher than that  123+ - I 'm not having issues - though I will now be using a bucking transformer.

Check all your wiring and voltages (amp instructions) and use a SS rectifier as advised by tubes4hifi.  These amps are hard on rectifiers - I had good luck with the WZ68 SS.

Also other bad tubes can cause it to short so hopefully your output tubes and other tubes are all of high quality and well tested - ex bought from someone like Jim McShane.

Thanks

Also - provide the system specs - what tubes are you using etc - that should help others chime in.

" I'd avoid the Weber WS1 like the plague - the WZ68 I've had good luck with and is the only one I'd use."

Can you explain why?  I use the WS1-t (thermistor) version in my ST120 and it's been fine for 2 years and I didn't blow 5AR4's prior to that.
I use a variac set to about 116-117vac and the auto bias board which has delay by design. I switched to the SS after installation of the AB.

Also, at this point, I think the plague is UN-avoidable

New2Tubez wrote:" I'd avoid the Weber WS1 like the plague - the WZ68 I've had good luck with and is the only one I'd use."

Can you explain why?  I use the WS1-t (thermistor) version in my ST120 and it's been fine for 2 years and I didn't blow 5AR4's prior to that.
I use a variac set to about 116-117vac and the auto bias board which has delay by design. I switched to the SS after installation of the AB.

Also, at this point, I think the plague is UN-avoidable

I posted a thread on this here.   Right after the rebuild of one of my M125s - I ordered two new WS1/Ts.  My tech went over the amp and replaced a couple bad resistors and a bloated cap - the amp was completely finished and working perfectly.

We took out the WZ68 and put in the WS1/T - powered up - terrible sound and bam - fuse blown.  We tried the other WS1/T - same issue.   We put back in the WZ68 - and worked just fine - we also put in a GZ37 Mullard - worked fine.

I couldn't get the WS1 to work at all - I sent back to Weber - they said nothing wrong with them - yet they couldn't explain why the WZ68 had no issues.   They were just as confused as I was.

The WS1 just turned on - made a terrible contracting sound from inside of it and fuse blown.  Like instant over voltage. I'm only running two output tubes - perhaps that is why -I just don't know - I never had issues with Rectifiers in all my years with these amps (2011?2012?)

Thanks for clarifying. That sucks.

At the time of my switch to S/S, I was going to get the WZ68 and I recall Weber stating NOT to use it for HiFi even though Bob had good success with it. I ended up with the recommended (by Weber) WS1-t.
There was a whole thing on this forum about it at the time and about sag and drilling the 68 copper for venting. I didn't want to mess with all that.

My teething problems were with the AB but those got worked out- also on the forum.