I tried the National brand 12AT7, and I did not like them compared to at least four or five other brands of European or US origin. In fact a Chinese made tube was the best of the bunch in my 12AT7 survey, but it had a very short lifespan which I considered unacceptable. The next best were GE gold star and Mullard. ECC81 is the Euro equivalent. ECC81= 12AT7. |
12AU7, 12AT7 and 12AX7 are pretty much the same tube with a different gain settingshttps://jaazz.me/2019/01/04/12ax7-12at7-12au7-preamp-tubes-differences-explained/amp/ |
When I Tube Rolled 6SN7 and Variants of this Tube. I did this without support or loans of tubes from experienced owners. In comparison to other Tube Rolling experiences, it proved to be the most difficult to make a selection, as some tubes choices, once with a little run time sounded like competitors to go on to a Short List. When longer evaluation periods were used for the tubes, certain tubes became very different in their SQ and had to be removed, as the deterioration was very obvious. There was a concern that the tube was developing a fault. I would say best to stick close to the advice of others with worthwhile experience as the selection for the initial investigations. A Benchmark can be set for any other experiences to be had down the line. |
@pindac no questions, advices of others with worthwhile experience is very valuable and of course could be implemented, but my senses and fillings r more important for me. You know it’s like advices from others which women is better for you… you listening to that advices but using your fillings in the first place. |
