Anyway this is a Dynaco Dyna PAS 3 preamplifier. That is to say it is my Dynaco Dyna PAS 3 preamplifier. Also, my cat.
It is in good, original working condition. However, there are lots of mods you can do to "improve" it's function. Some of them even help.
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Since it is working perfectly well, I've decided to mod it. My mods are based on this article from the mid 90's http://www.normankoren.com/Audio/Spice_preamp_2.html
however, vacuum tubes require little electric heaters to work, and that draws a lot of current. so much current, in fact, that you have to upgrade the power supply. that's a lot for a beginner's project, so I redesigned the circuit slightly to use mosfet transistors in the two added stages.
The layout of that page is appropriately old timey. Anyway the two main circuits go from a 4 tube layout to a 6 tube layout