S.E.X. Completed hum Resolved but problems with C4S install

[EnsgnofIndustry]

I had posted below about hum. Ultimately, I went back into the kit and re-soldered all the joints with a cranked up iron. I'm used to circuit boards, so I'm usually not too aggressive with a hot iron. In any case, the hum disappeared with the re-solder, and I had a good 3 weeks of regular listening with phones and speakers. Sounded great.

I just installed the C4S mod as per instructions (I think), and upon plugging in the amp to test voltages, I heard a loud crack. I quickly unplugged the amp and didn't see where the arc came from, but the Right Cap looks like it was damaged. The fuse remains intact. I have attached photos of the build. Not sure what happened. Do you see anything askew? Happy to take more pics.

[Thermioniclife]

It looks like in the first pic you laid the body of the iron against the cap and it could be directly shorted.

[Doc B.]

Yup that 1.5uF cap is toast. You need to replace it before doing anything else.

[email protected]

We will be back in the office on Monday.

[EnsgnofIndustry]

That thought did cross my mind but I didn’t notice it before I fired up the amp. I’ll send an email request.