Express build with intermittent noise

[stubbyfex]

I had an amp that would crackle and pop ever so often with the tube shield off. If I put the tube shield back on it would work fine! It turned out to be one of the pins for the socket had broken off just above the rear surface of the socket. The spring in the tube shield put enough downward force on the broken pin that it made contact. It had me going for a while. I fixed it by removing the broken pin, and taking one out of a similar socket, I was able to repair it without replacing the entire socket. I guess you could ohm out each of your tube wires from the socket to where they attach. Perhaps get one of those 9 pin plugs, and insert it into the socket so you could attach one end of your ohmmeter probe to the plug. Good luck in the search!

[billyz]

Last week I had this after 1 1/2 years on two Express builds
1. what I found I had used brass screws for my grounds
after time the brass corroded and made a poor contact black in color
I replaced all the brass screws with stainless steel with nylock nuts
and ran a jumper wire from the power tubes ground buss
Also I have switched to silver wire and solder.
No hiss or pops at full volume

Brass and aluminum chassis don't mix

Good Heads up on the Brass Aluminum interaction. I had been using brass screws for my grounds and will definitely rethink that.

What make of Silver wire are you using ? I have experimented with Silver wire before and found it to be very silky sounding and detailed, definitely better than copper, but that was in some HiFi amps and speakers.