Just finished the Mojotone TMB kit, PPIMV?

[ejendres]

Hey gents. I've done some more work on the 18watt. I shielded the inputs, changed the grounding to be a star ground, added a 'zener clamp mod' to the he power amp to prevent bias excursion and added a grid stopper on v2b. I've attached the modified schematic (I used a 13V zener as that's what I could source).

Mods (1).png

I think the mods helped tighten up the low-end a bit but it seemed to make the low-end distortion more apparent, take a listen:
https://soundcloud.com/ejendres/loose-farts

I want to scope the amp and try and figure out what the distortion is. Is there a guide I could reference? I haven't used an oscilloscope since college nearly 15 years ago.

[Bieworm]

That zener thing is not the Paul Ruby Mod.
Look at how it’s done here: files/JMPGuitars_18_Watt_EF86_Modern_Cl ... ematic.pdf

[chaliapin]

Have any of the knowledge members listened to the clip? Interested to know their opinions.

[ejendres]

Have any of the knowledge members listened to the clip? Interested to know their opinions.

I was wondering the same thing.