So I just received four '58 Foton 6N8S's. Seeing as I already have umpteen million of them, why more? I have to experiment here for my own edification. Check out the beautiful soldering job on these pins:
I'm pretty sure my pin soldering skills are pretty lame, but I'm also sure that even my worst soldering attempts look better than this. None of the ribbed plate versions I have ('56 and prior) have pins that look *this* bad. So my question is simply are the '50's versions with ribbed plates really better than the non-ribbed, or did something else change in the process at the same time the plate design was changed? Maybe the non-ribbed sound just as good as the ribbed, but the soldering quality suffered a big decline when things changed which makes the tubes sound subjectively worse. So, I'm going to completely remove and replace the solder in 2 of these, and leave 2 as-is. I'll test them to see how they match up with GM (and I have some other '58's I can add to the mix if I don't get good matches with these 4). After re-doing the solder, I'm going to give all four tubes about 5 hours of burn-in in the Cary. Most truly unused tubes do have sonic changes initially (at least in the first few hours) so I want to rule that out as a variable as best possible. Then I'll put 100 hours on one of the re-soldered ones and one of the as-is ones, and then compare them to the two that have only 5 hours. And them compare those to some well broken-in (more than 100 hour) ribbed plate versions, one with reflowed (but not totally replaced) solder and one that hasn't been touched with a soldering iron. Why is this important? I have no friggin' idea, other than I wonder about it and I hate wondering about things.