lowering output power by reducing screen voltages

[sepulchre]

Hey Shane! Nice to see you here. (Ken)

Martin: I built the Jana style 2204 (ish) 50W as well. I put a PPIMV in it (I often leave that all the way up) and it sounds Really Great! I use it a lot around the house too but it's certainly got enough guts to keep up on stage if needed.

[martin manning]

I built the Jana style 2204 (ish) 50W as well. I put a PPIMV in it (I often leave that all the way up) and it sounds Really Great! I use it a lot around the house too but it's certainly got enough guts to keep up on stage if needed.

You have two MV's? If so how do they compare tone-wise? Is your layout traditional or non-traditional?

[sepulchre]

Well, the simple MV really just controls the PI overdrive unless the PPIMV is dimed. It's transparent then so the simple MV works like normal. But even with the PPIMV turned down to less than half it sounds really good. I was expecting more of a hit on the NFB but, though you can indeed tell the difference, it's not too bad. But obviously there's no power tube break up with it down. Still, I love the sound. It's easily my favorite amp - soo smooth!

Is my layout traditional? Hmm. I'm not really that familiar with what's traditional, but here it is:
[img584]http://i269.photobucket.com/albums/jj55 ... 73c909.jpg[/img]

Miles said it looks Wreckish - probably because things are so spread out. The chassis was meant for an amp with a lot more going on (note the unused holes in the front). That didn't work out so after a few abortive attempts at other designs I wound up building this instead. If I were to do another like it I would use a smaller chassis.

[Reeltarded]

Been about two years since I stopped playing non-mv amps at this point. The PPIMV+ simple master really works great together.. throw in a CF master and you have control of just about everything that matters.

Love that!

[FUCHSAUDIO]

Marshall scaled the screens in the Slash amp. have fun!

Not fair Jelle: That amp had a rather sophisticated microprocessor based regulator that adjusted both screens and grid bias to reduce power . Not something for the layman. A simple VVR regulator can be used to drop screens easily and safely. I would avoid variable wattage and/or variable bias scenarios, unless you are fairly advanced technically.