#1
hey UG, im using a valveking 212 tube amp, and 30 seconds or so after i turn it on, it starts "crackling." this will go on for about 3-4 minutes, constanly getting louder and softer even if my guitar is unplugged. i replaced the tubes about 1 month ago, as i thought that was the cause of the crackling, as it was doing it with the old tubes also, but it did not fix the problem. any ideas?
#2
Its a preamp tube, the same thing happened to me with my Triple X with a less than year old JJ tube.
Agile AL3000
Douglas WRL90
SX SR1 STD Plus
J&D Strat
Squier Tele
Sammick TR2
Douglas Draco
Peavey JSX
Bugera V5
TWANGED VJ
#3
+1

It is an overly microphonic preamp tube. I had the same problem with my VK but it is not specific to a VK (could happen to any amp). I also happened to have this test vid handy. Use this to find your microphonic preamp tube and then replace that tube.

http://s545.photobucket.com/albums/hh384/buckethead_311/Amp%20stuff/?action=view&current=Microphonicpreamptube.flv


Edit: could be a bad cable or scratchy potentiometer I suppose.
Last edited by 311ZOSOVHJH at Aug 25, 2010,
#4
thanks guys u were both right, my v1 is microphonic. still dont understand why it broke so quickly though.
#5
Quote by blorgy
thanks guys u were both right, my v1 is microphonic. still dont understand why it broke so quickly though.


They don't break necessarily. All preamp tubes are microphonic by nature. When they become overly microphonic is when it becomes a problem. Peavey doen't use the greatest tubes in their inventory tbh when it comes to the lower end amps like the Valveking. That preamp tube could have been sitting in a factory for 3 years waiting to be put into an amp. Other factors affect tube life obviously but you get my drift.

I was not happy with the stock EHX preamp tubes in my VK but I did mess with some JJs and a 5751 with good success. Tung Sol not so much.


Check the VK thread and Wiki for tube recs.
Last edited by 311ZOSOVHJH at Aug 26, 2010,