This project started by coming across an old amp carcass I had gotten off eBay years before and just shelved. It turned out - after some research - to be an H.H. Scott hifi type of amp. The transformers were pretty beefy. Even though the original amp had run 6V6 tubes, I felt that I might be able to make a 30'ish watt bass amp using 6L6 tubes. First, I temporarily wired the transformer up, using the most dangerous method I could think of, to see what voltage could be had.




I got 500vdc with no load. I figured even with overloading the "rated" capacity (whatever that might be) it should still give me 400 vdc on the plates of the power tubes. So with that, I bent the metal for chassis and made the holes...





The wires coming from the power transformer (PT) were short and quite stiff. I was afraid with much repeated bending the wire would break.



Used a terminal strip to give me something solid to solder to, and keep those ancient wires in one place, one piece.





This was my first time using adjustable bias instead of cathode bias for the power tubes. I stole this excellent idea for making each tube's bias adjustable from a fellow on the amp forum where I've gotten nearly all of my (limited) knowledge. This allows you to change power tubes and re-set bias -if needed - without opening up the amp. Test points and locking bias pots are on the outside, in back.



Getting towards the finish line now...



...and the inside is done... now to mount it in a box...







The wooden cab was made by another forum member who does excellent work! He really should quit his day job and just make cabs. The gold grille I got at Ace Hardware. It's aluminum and easy to work with.


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