5 Watt Plexi with 6F4P power tubes

This is an amp currently in development but I think it’s actually pretty much done.

It’s a little Marshall Plexi type amp that uses 6F4P power tubes which are Russian ECL84 equivalents. These are little 9 pin tubes that have a power pentode and a triode in the same bottle. I used them for the power tubes and the triodes for the LTP phase inverter. It’s pretty much based on Mark Huss’s 6V6 Plexi design. I added the split load plate resistors on the PI to reduce the gain driving the 6F4P power tubes. They are very sensitive and can get unhappy driven to hard.

Here’s the current schematic but it might change:


Here is a clip:

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