Hi!
As mentioned above the 211 and 845 did not have the issues which the 300B had. They suffered from the poor quality control as well. During the time I was distributor for Elrog I got only very few returns of 845 tubes.
Life time cannot be generally estimated since it depends a lot on the operating conditions. During the many problems with the 300B we learned that there are a lot of amps which push tubes too hard. This can shorten the life time. op point, usage pattern (on off cycling) and tube rolling all affect lifetime. Normally you should be able to expect 3000-4000 hrs from a thoriated tungsten power tube. This can drop significantly if the tube is abused. It can also extend well beyond that number if the tubes are handled well. The distribution is a kind of bell curve
We also do not make the 845 long enough under the new company to have significant statistical data. I do not expect any issues with the 845 though.
Like the 300B the 845 and 211 carry a full year warranty now.
Best regards
Thomas
As mentioned above the 211 and 845 did not have the issues which the 300B had. They suffered from the poor quality control as well. During the time I was distributor for Elrog I got only very few returns of 845 tubes.
Life time cannot be generally estimated since it depends a lot on the operating conditions. During the many problems with the 300B we learned that there are a lot of amps which push tubes too hard. This can shorten the life time. op point, usage pattern (on off cycling) and tube rolling all affect lifetime. Normally you should be able to expect 3000-4000 hrs from a thoriated tungsten power tube. This can drop significantly if the tube is abused. It can also extend well beyond that number if the tubes are handled well. The distribution is a kind of bell curve
We also do not make the 845 long enough under the new company to have significant statistical data. I do not expect any issues with the 845 though.
Like the 300B the 845 and 211 carry a full year warranty now.
Best regards
Thomas