I have connected the grid, of the lower second stage tube and removed the "primary" of the EXO-173. This was the closest symbol that CircuitMaker had. In Paint I was able to edit it .

this is a work in progress. After Dimar’s excellent series on the design of the SE amp, I though it would be fun to do a ‘practical’.

As it stands now, the amp sounds OK, not great. there is a bit too much bass. I will try reducing the size of the coupling caps.

There is a bit of ringing on the leading edge of a 1k square wave at the output but this may be normal for a P-P amp with no feedback.

Anyone with any ideas, let’s hear them, I’m not proud…John