#1
Hi,

I have just bought a Bugera 333XL with the 4x12 cab and have a problem out of the box. This is my first stack amp so I am wondering if I have missed something obvious.

When I power everything on it works fine for about 60 seconds. Then I get a popping noise every 10 seconds which will quicken to up to 3-4 seconds. This happens with no guitar plugged in and all settings at zero. It stops if I turn standby off.

It came with EL34's which are currently biased to about 44V (which I think is a little high - the Bugera manual provides different voltages for different tube grades and I dont know which one to use). I have plugged in the cab and set the speaker switch to 16ohm. The cab has been set to mono and a guitar cable plugged into the input (ahem).

Do any of you guys have any idea what I could be doing wrong or what could be wrong with the amp itself?

Thanks
Mike
#2
You should post this in the Bugera Thread. I can't really help you as much as I'd like, I've never set up a cab/head before. But the tubes are biased too high.

As I said, post this in the Bugera Users Militia and the more experienced guys will sort ya out
HOWAYA LUV ;D



BUGERA USERS MILITIA
#5
Quote by 24seven
Hi,

I have just bought a Bugera 333XL with the 4x12 cab and have a problem out of the box. This is my first stack amp so I am wondering if I have missed something obvious.

When I power everything on it works fine for about 60 seconds. Then I get a popping noise every 10 seconds which will quicken to up to 3-4 seconds. This happens with no guitar plugged in and all settings at zero. It stops if I turn standby off.

It came with EL34's which are currently biased to about 44V (which I think is a little high - the Bugera manual provides different voltages for different tube grades and I dont know which one to use). I have plugged in the cab and set the speaker switch to 16ohm. The cab has been set to mono and a guitar cable plugged into the input (ahem).

Do any of you guys have any idea what I could be doing wrong or what could be wrong with the amp itself?

Thanks
Mike


your tubes need be biased at no more then 42.5mA. the stock BUgera are not the best and come biased either WAY cold or WAY hot. there factory bias intructions are a joke. id bias it down to about 36-39mA. i use Kt77s(which are a el34 type tube) in my 6262 head. i keep my bias around 36-38mA.
Gear:
Mesa MK IV head
Mesa 4x12 cab(3)
Marshall JCM900 2100 SL-X
BBE 482i
ESP eclispe II
B52 At-100 head
MXR and Boss pedals
Sparow guitars
Peavey 5150 II modded
JJ electronic tubes

BUGERA USERS MILITIA