Howdy ho!
It's been a good time for amp builds and mods on my side. Have finally tweaked my Plexi 6V6 to where it tops my 18 watter...
In fact, it's kind of ruined the "plexi" side of my 18. The normal channel of the 18 is still wonderful though.
Time to get the soldering iron out! I don't need two plexi style amps, the 18 normal channel can do the non TB vox/early marshall EL84 thing. Figured I'd try the Marwatt circuit. I kept the 18 watt lite IIb portion of my amp, but the have changed the following:
Marshall lead tone stack to hi watt values - fierce!
12ax7 in v2 to 12au7 - lower gain
v2 cathodes from 2k7/0.68 and 820/0.68 to 1k5/0.68 - changes the gain staging
Gain control removed, and mid pot changed from 25k to 100k
Hell's teeth this thing is good! Crank it to the sweet spot and it does "The Who" like nothing else. Flick of the wrist and it's searing gain, ease the attack and it's crystal clean. Without even touching my guitar's volume pot.
And it takes pedals brilliantly. I swear my tone bender was made for this thing.
And I've still got the amazing lite IIb channel.
If you're considering an 18 build, this variant is well worth checking out.
Ironically, the two amps' cosmetics are the wrong way round. Plexi is on top, Marwatt on the bottom. Need to get new faceplates made up, and going to switch the piping on the heads over the weekend.
Clips soon!