Small plate format dual triode, with low microphonics and superior dissipation, compared to NOS originals. Ideal for reverb circuits. Extra-low microphonics makes it the best 12AT7 choice for sensitive circuits.
I recently came across a few boxes of Genalex B759 tubes. Unfortunately the boxes are empty, but I still wanted to share with everybody the amount of effort that went into creating these boxes and what goes inside of them including test report sheet.
Thanks to all of you, we finally achieved a new milestone – 300,000 unique visitors to the site. That is a lot of people that the community and we at Tube Maze hopefully helped to learn more about the exciting and confusing world of tubes.
There is a lot of confusion about matching tubes. It starts with some vendors, especially on eBay, matching tubes by the way they look (visual matching) to matching on multiple electrical parameters at the same time.
There are 4 parameters that could be used to match preamp tubes:
Once in a while, while going through a new shipment of tubes, I find some true treasures. This time it was an incredible find, the legendary CBS-Hytron 5814 tubes, but not just that, they were engineering samples from CBS-Hytron. Engineering samples were sent to various manufacturers to get acceptance and determine interest before starting mass production. Unfortunately, there is no date code on the box or the tubes, so it’s hard to say when it was produced exactly, but considering that 5814 tubes have been produced since October 1949, these are not far behind. Notice, that there is not 5814 label on the glass, just on the wrapper.