Prototyping

Since designing an amp requires lots of iterative suck-it-and-see (as the British say), I decided I needed a quick and easy way to make circuit changes.  I considered using a bread board, but those aren't usually rated for more than 120 volts and mine will be running about 300 volts.  My father often used barrier strips for experimenting and I happened to have about 10 of his old bakelite strips from the 50's.  I mounted those to a piece of Masonite, added 4 feet and I had my prototyping board.  The screw heads make it fairly easy to swap components.  Here's my first working single channel amp showing the power conditioning (top), a 6SN7 driver (large tube) and a EL84 power tube (smaller tube).

That prototype was a bit low powered and had quite a bit of midrange distortion.  I soon was on a quest for a set of tubes which would suit my needs better.