Power Scaling 100w amp...which vvr?

[amplifiednation]

I accepted a power scale job for a customer getting a recover done on his Marshall head, jcm2000 100w model. I was just gonna use one of Dana Halls boards and try to navigate my way through the city of PCB's I know are in there. Then I found that the Hall boards only go to 50watts...do I need to go to London Power or are there alternatives? I can also skip it altogether but i thought it would be cool to do.

[Cliff Schecht]

I would skip that for sure. JCM2000's are junky amps anyways and you are risking putting something in there that will cause further reliability problems. If it was a custom amp it would be a different story but I rarely mod modern PCB amps past the point of a few component changes. That amp has a MV already and makes most of its distortion in the preamp so an attenuator is pointless IMO (the output stages are typically biased really cold and make no distortion to speak of).

[amplifiednation]

Good point Cliff. I was literally just reading a thread about cleaner power stages not being good candidates for vvr. Maybe I will just put another master volume on the back...hehe jk.

I do want to get one of Dana's boards for my Express. Maybe then I can actually play the amp!

[Zippy]

I do want to get one of Dana's boards for my Express. Maybe then I can actually play the amp!

Have you considered a Trainwreck Airbrake (attenuator)?

[amplifiednation]

I do want to get one of Dana's boards for my Express. Maybe then I can actually play the amp!

Have you considered a Trainwreck Airbrake (attenuator)?

Yeah I built an attenuator. It works well but i hate pushing my NOS Siemens EL34s so hard. i have some JJ 6V6 I just got, I'm going to put those in there as i won't care if they burn out quick.

My express needs some love. it's like 90% there. i want to change the bright switch values and my jack isn't shorting properly. i never burnt in the amp either, which I will probably do once my current build is done roasting. It needs to mellow out a bit.