TriodeLuvr wrote: ↑
Fri 05/14/21 8:37 am
JMPGuitars wrote: ↑
Thu 05/13/21 5:59 pm
Changing the screen resistor is only one way to change the relationship. There are better ways to do it.
That might not be true, Josh. Dropping screen voltage with a simple series resistor allows screen voltage to wiggle around and to drop even further when the tube is overdriven. I'm convinced this contributes to a smoother breakup. Other methods, such as a series Zener or a voltage regulator, or even just bypassing the screens with a capacitor after the resistor, won't produce the same effect. This is one area in which I think you and I are in agreement, i.e. larger screen resistors improve the overdrive sound.
Ironically, my current hi-fi project with 6L6 types will apply 100V less to the screens than the anodes. I'm using a gas VR tube in series from B+ to produce the drop. The screens won't be stiffly regulated at a fixed voltage, but they will be locked to the anodes over variations in B+. NOT a good technique for a guitar amplifier.
lol, we do agree on stuff. Hell, I agree with your HiFi stuff too...when we're talking about HiFi.
And when I eventually have enough free time to make a HiFi amp, I'll definitely pick your brain on it.
You and I dig the higher screen resistor sound, but in this case, we have no idea what any of his voltages are. My guess is the screen resistor play is making up for something else.
To be clear, my intent is for him to use a higher screen resistor value, and correct the tone through other means.