Got a couple RCA 6AS7’s and so far so good.
I included a shot below of the 6080 that shipped with the kit. You can barely make out some black specs behind some of the thin wires. This is the spot where the arcing occurred and the brighter spot on the tube itself when running.
I noticed with the newer tubes I put in, no more sparking either when inserting the headphone jack in and out. I’m thinking the inserting of the jack was just enough to jostle whatever was in the tube to cause the spark and pop. Going to leave it running for a bit longer to see if anything happens again though.
Also curious, when I originally tested the Crack I used my cheaper Sony MDR-V6s. They are much lower impedance than what is recommended to run, could the lower impedance have caused the pop to be much louder than what would have been with my HD650s? Don’t want to risk damaging my nicer headphones, but I didn’t find any other stories of blown drivers when searching, so I would assume that’s pretty out of the ordinary. Also don’t want that to happen again while I’m listening.
Sorry, but cannot for the life of me attach an image. Keeps telling me I’m not using a .jpg.
(https://i.imgur.com/yBL1pW0.jpg)