fusedbrain":3njy3pvr said:Yeah, great idea. I'd love to do that, but where the hell do you get a 5watt pot??FourT6and2":3njy3pvr said:fusedbrain":3njy3pvr said:Yup, classic example of fitting the mods to the amp at hand. I'm dealing with this now in my amp.I think you mean soft? 22K dropper will make the amp much looser and more gainy. But... it depends on what the starting voltage is. Maybe that particular amp had a really high B+. That's why you can't just use any old schematic verbatim. There are lots of components in an amp that must be tuned specifically for that amp. Like the B+ dropper. If the B+ is like 500V, then maybe a 22K dropper makes sense. But if the amp has a 425v B+, the a 22K dropper is going to equal mush city.
For example, in a stock 1987xl,the first droppers after the choke are 2 x 10k's in series, but my PT is only putting out 460v B+.
After subbing in a 330k plate load resistor on the first triode, the plate voltage there is only 105v .
That ain't gonna work for what I'm after from this amp, that's for sure!
You can probably go down to 10K on that dropper then. I have a 5-watt, 50K pot that I clip in for the B+ dropping resistor and tune the amp with that. Then solder in the final value.
https://www.mouser.com/ProductDetail/CT ... pEgnZJY%3d