Hi Everyone,
I updated the measurement list on my website.
1. I included a few more samples of Shuguang 12AX7B and Shuguang 12AT7.
2. I included new measurements made on the JJ EF86 (they call it EF806S). I've read in many places that pentodes are noisier than triodes, but I've never measured it before and was very curious to see how much. The EF86 measurements make it one of the higher noise tubes I measured, but not the highest. I also measured it as a triode, because I've read that a triode-connected pentode should produce less noise. At least in this case, it did not seem to be true. Within the accuracy of my measurements, it was the same. Hmmm......
3. Finally, I have begun to compute sample standard deviation (sigma) instead of posting the min & max for each type. Standard deviation is a better way to compare data sets of different sizes.
Scott
I updated the measurement list on my website.
1. I included a few more samples of Shuguang 12AX7B and Shuguang 12AT7.
2. I included new measurements made on the JJ EF86 (they call it EF806S). I've read in many places that pentodes are noisier than triodes, but I've never measured it before and was very curious to see how much. The EF86 measurements make it one of the higher noise tubes I measured, but not the highest. I also measured it as a triode, because I've read that a triode-connected pentode should produce less noise. At least in this case, it did not seem to be true. Within the accuracy of my measurements, it was the same. Hmmm......
3. Finally, I have begun to compute sample standard deviation (sigma) instead of posting the min & max for each type. Standard deviation is a better way to compare data sets of different sizes.
Scott