This is the story of the so called "BAD BOY"
On HiFi head there was a question put out on ’what was your favorite 6sn7’ tube. This was about 16 years ago.
Some new guy shows up and says ’his Sylvania 3 hole tube is a Bad Boy’ on his earphones. He had nothing else to compare his tube to. That was that.
Members promptly examined the tube to be made between March and July of 1952, that is the period. The big source for any tube then was eBat. Some bought the tube and immediately said it was plain, nothing great.
Suddenly EBAT is flooded with 3 hole Sylvanias regardless of what year or month they were made. let me repeat that...a span of nearly 2 plus years and they are all the ’Bad Boy" this newbie heard, simply because they have ...3 holes.
A $3.00 tube went up and up, and no would admit it was just plain, but instead resold them as THE wonderful, highly sought after "Bad Boy". Well guys it is a plain $6.00 6sn7, period. I have several stock picks for you, by the way, if you are interested.
Try a 1940’s metal base Sylvania or the Russian one, and tell me how great they are next to this 3 hole folklore.