Gibson GA 5t whitepanel making crackle, pop, fizz

[nsubulysses]

As an aside, say you were rolling a tube in Tom Phillips interpretation and as you rocked and rolled it circularly to test it, it continued to be noisey, and crackley? after cleaning and retensioning the sockets, re-soldering all the pin connections just in case, and trying different tubes, would you replace the tube socket next?

[Jazz P Bass]

Well that all depends on how you "rocked and rolled it circularly to test it".

The socket tabs are two circular pieces of metal.
If you happen to break that connection, it will crackle.
The tabs do there best to hold the tube in place.
In an amp, they may vibrate but the tube will most certainly not try to twist in a circular motion.
A gentle tap is about all I will do a tube.

Also it depends on the circuit in question.

Just sayin.

[davohilts]

Thanks everyone for your help! I've been away from my workbench but am back today and have been working on solving the crackle. I focused on 6C4 tube as Tom Phillips suggested and replaced the 1K cathode resistor without any change. I started poking around with my chopstick on the tube connections after resoldering them and when I touched pin 1 (a pin without any connection) the crackling increased so I moved the tab around a little and the crackle went away. I went back and retensioned the pin sockets and cleaned them again with contact cleaner, then replaced the tube. The crackling is gone. I also checked the bias and found that with the 150 ohm cathode resistor per spec the bias was 10.8 watts. I had a 200 ohm 7 watt resistor that tested 184 ohms so I put it in and now I'm getting 8.4 watts bias on both tubes. I now am going to put the amp back together and try a few 10" speakers I have to decide which one sounds best. This amp is sounding good and I'm excited to play thru it.
thanks again for helping me focus my attention to where I needed to be. Sorry for any confusion on tube rolling, that is what I've always called trying several tubes as a trouble shooting technique.
Dave