Bugera 6262 help (solved)

[bryanarzaga]

I have a bugera 6262 non infinium and when i changed the stock power tubes(6L6GC) as those were dying to another matched quad 6L6GC, i noticed the gain was not what it used to be, the beefy tone/sound just went away. it also been picking alot of radio interference in both clean/dirty channels


Thank you

[JazzGuitarGimp]

Is the output stage fixed- or cathode-biased? If it's fixed, did you re-bias the amp after you replaced the 6L6's?

[Stevem]

If your output tubes where weak,, then new ones that where in better shape would be pulling more current with the same bias setting and this would provide the same if not bigger / fatter sound than what you had before!
Just because tubes are new and matched does not mean they are strong new tubes!
How did you conclude that the old tubes where weak, by means of a Tube tester that checks by means of trans mutual conductance and not just emission?
A weak PI tube can make it seem like the power tubes are failing!
If this is a multi speaker combo amp you may have knocked a speaker lead off of one off the drivers during the tube swap over.

[bryanarzaga]

Is the output stage fixed- or cathode-biased? If it's fixed, did you re-bias the amp after you replaced the 6L6's?

yes i did, it can switch between el34 and 6l6 and i followed the bias processing using a bias probe

[bryanarzaga]

If your output tubes where weak,, then new ones that where in better shape would be pulling more current with the same bias setting and this would provide the same if not bigger / fatter sound than what you had before!
Just because tubes are new and matched does not mean they are strong new tubes!
How did you conclude that the old tubes where weak, by means of a Tube tester that checks by means of trans mutual conductance and not just emission?
A weak PI tube can make it seem like the power tubes are failing!
If this is a multi speaker combo amp you may have knocked a speaker lead off of one off the drivers during the tube swap over.

the old tubes sounded great for a a while and then they started sounding muffled, loss of treble and whatever i do with the eq it was not helping much, then it started loosing gain/distortion

so i thought buying replacement quad will help me, i did however have pair of 6L6 and plugged those in initially (outer slots) and biased those, but i did that for a like a few minutes and concluded i should just wait for the quad set

[bryanarzaga]

dudes..faulty PI tube ..well i got to experience this the first time

[Stevem]

good to hear you got it crankin!