Having too much fun! have some 6Y6s and 6K6s, want to see what lower power tubes do. Am looking at tube data sheets, plate voltages, cathode bias, plate dissipation, AND power supply loading. Realized I had been using my Champ-sized PT (70 mA) on this Deluxe breadboard. Am drawing 80 - 100+ mA..... OK, so how do I reduce the supply current demand? Plugged in two 6K6s, tube data showed similar plate B+ and cathode resistance (400) to 6V6s, and the amp worked well, only 32 mA plate current at 345 V on plate (6V6s ran at 41). Still too much draw on the supply. This is where I know just enough to be dangerous..... Thought I could lower the plate voltage with dropping resistors on the plate leads. Installed two 1800 1W guys, and.....one 6K6 showed 317V on its plate, the other 372!! And then the amp started fading (have a 4 ohm spkr cab and 4 ohm dummy resistor switchable, and a sig gen at guitar level providing signal). Current draw from the supply dropped off. Shut it down. Removed the plate resistors, everything still works. Hmm... How can I lower plate supply (other than a whole different xfmr/tube or SS setup? Preamp tubes use that 100K to set plate voltage... The 6Y6 needs only 200 V of plate voltage... Any thoughts? Thanks! Jeff
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