Yes they are.
Master Volume Mod
- Thread starter Johnny Cache
- Start date
This site may earn a commission from merchant affiliate links like Ebay, Amazon, and others.
Platefire
Friend of Leo's
If you want more feel and more distortion a post PI is the way to go. A post PIMV is more versatile IMHO if it will work on your particular amp. I just installed Lar-Mar PPIMV for a customer on a 72 Marshall 1987 50 watt(I know sacrilege) and it worked real good from pepped up clean tone, to overdrive to full blown distortion.
I've presently been playing on a 1958 Dukane PA head converted to a 5F6A Bassman circuit with a pre PIMV. I basically play clean but set the volumes to get clean a low guitar vol and hair at high guitar vol. So to get what I like on this amp the pre gain is set at 3:00 oclock and Master Vol is set at 9:00 oclock--pretty extreme. This setting sounds great to me with my tele or strat. The schematic pix of the Dukane is attached. Pre PI is a little less effective than a post PI MV. I use pedals to get my OD and Dist.
I've presently been playing on a 1958 Dukane PA head converted to a 5F6A Bassman circuit with a pre PIMV. I basically play clean but set the volumes to get clean a low guitar vol and hair at high guitar vol. So to get what I like on this amp the pre gain is set at 3:00 oclock and Master Vol is set at 9:00 oclock--pretty extreme. This setting sounds great to me with my tele or strat. The schematic pix of the Dukane is attached. Pre PI is a little less effective than a post PI MV. I use pedals to get my OD and Dist.
Last edited:
Type 2 with 1.8M bias safety resistors:
FenderLover
Poster Extraordinaire
It's hard to see the figures in the GP article, but the text indicates the second set of caps are 0.022uF. That makes sense, because if they were all 0.1uF, each are in series producing 0.047uF which may be too much.
Last edited:
Platefire
Friend of Leo's
Not sure on that, the 1.1 Lar Mar I posted is pretty simple in that it don't require you to add extra caps and you remove the two 220K bias resistors. The one I installed the dual 250K L Pot went in the extra external speaker jack that was removed. The two leads from bias resistor to pin 5 on power tubes is also removed. Then for the MV hookup, you got three leads going from board to MV and two leads going to pin 5 Power tubes. If you did it correctly, saved you parts removed, would be a easy mod to undo and put back stock if you didn't like it. Platefire
The Type-II simply replaces the power tube grid leak resistors with a dual pot. At max volume it's equivalent to the stock resistors. In my opinion it is the best post phase inverter master volume.
Platefire
Friend of Leo's
Not sure on that, the 1.1 Lar Mar I posted is pretty simple in that it don't require you to add extra caps and you remove the two 220K bias resistors. The one I installed the dual 250K L Pot went in the extra external speaker jack that was removed. The two leads from bias resistor to pin 5 on power tubes is also removed. Then for the MV hookup, you got three leads going from board to MV and two leads going to pin 5 Power tubes. If you did it correctly, saved you parts removed, would be a easy mod to undo and put back stock if you didn't like it. Platefire
Similar threads
