12-07-2025, 09:41 PM
Just a quick update: I have both amps pretty much completed and been listening to them every chance I have. I'll post all the gory details and changes along with my final schematic drawing once I put the bottom on. There's still some minor changes I might make like moving the bias adjustment underneath accessible through a hole so someone doesn't mistake it for a volume control or something. Also a pot to adjust the brightness of the indicator light. One MAJOR change I made was using EL34 output bulbs instead of 6L6GC. I was having problems getting much more than 32-35W with those and a tube rectifier, whereas I could easily achieve 40W with the EL34s. It DID sound GREAT with the 6L6s, but lack the drive needed from the voltage amp. I did experiment some with adding a tube between the pentode and inverter, but didn't work well at all. So, as it is, it sounds strong and clean. It's simple. So far, been working great. I'm inclined to close it up, do a final write up and call this one finished. I have the stuff to do another using the Mullard circuit or similar to get the drive I need for the 6L6s.
Now - I CAN get a full 50w using the EL34s IF I plug in the solid state rectifier. It raises the B+ by about 20-25v, but I already have it set up for the tube. So, it stays. I'm gonna leave it alone. Better to start a new build later.
Now - I CAN get a full 50w using the EL34s IF I plug in the solid state rectifier. It raises the B+ by about 20-25v, but I already have it set up for the tube. So, it stays. I'm gonna leave it alone. Better to start a new build later.
If I could find the place called "Somewhere", I could find "Anything"
Tim
Jesus cried out and said, "Whoever believes in me , believes not in me but in him who sent me" John 12:44




