Unless you swap the tubes in both sockets to see if the hiss stays with the tube or the socket, there is no way of telling if it is a bad tube or a bad mechanical connection. You could have a bad tube and it decided to show itself that day. Or you could have pulled the tube out or inserted into the socket in such a way that loosened the socket connection. Or... the socket could be soldered to a circuit board and the high heat compromised the solder joint and wiggling tubes in and out of that socket broke the solder joint.
Wiggle kt170 base
Hello everyone,
The sound on my tube amp was pretty good with the kt170. But I made a mistake. I took out the 4 kt170s and put in kt120 to understand the differences more. Next day I put back the the kt170 each into their exact slot from before.
There is hissing on the right speaker and a rare medium pop now. The very left kt170 has a very slightly loose base. Does this affect sound? I have no more intention of removing the kt170s if the loose base doesn't affect sound I'm fine to leave as is.
Could you teach me more about this hissy sound? I didn't touch any of the pre-amp tubes and they are all mostly nos. The hiss is softer today than it was yesterday.