Bugera 333xl issue. Please help
- Thread starter IKSLIM
- Start date
- Status
Phantasmagoria
watch where you point that sabre
Re: Bugera 333xl issue. Please help
Man...mine's never sounded like that ..what's it like with a guitar plugged in :boggled:
Man...mine's never sounded like that ..what's it like with a guitar plugged in :boggled:
Re: Bugera 333xl issue. Please help
Last time i had my amp squealing like that was when my v1 preamp tube went microphonic. If you have a spare preamp tube around try replacing it with each of the preamp tubes one by one, if the noise goes away then you've got a bad tube in that amp.
Last time i had my amp squealing like that was when my v1 preamp tube went microphonic. If you have a spare preamp tube around try replacing it with each of the preamp tubes one by one, if the noise goes away then you've got a bad tube in that amp.
IKSLIM
New member
Re: Bugera 333xl issue. Please help
Hank-, thank your for reply. I’m about to buy a new set of valves, but:
I tried separately preamp section and power section via Send-Return management:
Preamp section (input>>send) sounds clean at any drive, any chanel.
Power section (return>>cabinet) sounds clean at any volume also.
Both sections (input>>cabinet) results crazy whistling…
I appreciate your comments.
Thanks.
This is not a stupid question
Thank you for reply. I tried short cable, short cabinet cable, speaker-isolation-cabinet, Torpedo-Live – all the same. It is definitely inside feedback, and “microphonic” tube issue is likely the answer…
Hank-, thank your for reply. I’m about to buy a new set of valves, but:
I tried separately preamp section and power section via Send-Return management:
Preamp section (input>>send) sounds clean at any drive, any chanel.
Power section (return>>cabinet) sounds clean at any volume also.
Both sections (input>>cabinet) results crazy whistling…
I appreciate your comments.
Thanks.
This is not a stupid question
Thank you for reply. I tried short cable, short cabinet cable, speaker-isolation-cabinet, Torpedo-Live – all the same. It is definitely inside feedback, and “microphonic” tube issue is likely the answer…
Last edited:
devastone
Well-known member
Re: Bugera 333xl issue. Please help
A cabinet cable will always be noisy plugged into the input, they aren't shielded.
But, it is interesting that it is clean when you use just the preamp. That said, I still would recommend starting with the preamp tubes, if that doesn't fix it, it is probably a bad capacitor in the preamp section that is letting it oscillate. Unfortunately that is probably a trip to a tech, can't really diagnose that through the interwebz.
A cabinet cable will always be noisy plugged into the input, they aren't shielded.
But, it is interesting that it is clean when you use just the preamp. That said, I still would recommend starting with the preamp tubes, if that doesn't fix it, it is probably a bad capacitor in the preamp section that is letting it oscillate. Unfortunately that is probably a trip to a tech, can't really diagnose that through the interwebz.
IKSLIM
New member
Re: Bugera 333xl issue. Please help
I’ve checked PowerSection one more time = the issue is there, not in a preamp. Return (as input) >>Cabinet signal chain generates whistle if the input-signal amplitude rise. If the input signal already distorted (lots of harmonics) the whistle starts earlier.
Power tubes "live indicators on the backside" does not blink. I haven't got any EL34 tubes to replace. I am lost…
Any idea???
I’ve checked PowerSection one more time = the issue is there, not in a preamp. Return (as input) >>Cabinet signal chain generates whistle if the input-signal amplitude rise. If the input signal already distorted (lots of harmonics) the whistle starts earlier.
Power tubes "live indicators on the backside" does not blink. I haven't got any EL34 tubes to replace. I am lost…
Any idea???
Shooter.556
New member
Re: Bugera 333xl issue. Please help
Maybe its trying to talk to the mothership?
Seriously though, I'd look at tubes. I'd bet one has gone out..
Maybe its trying to talk to the mothership?
Seriously though, I'd look at tubes. I'd bet one has gone out..
IKSLIM
New member
Re: Bugera 333xl issue. Please help
I'd have to buy set of EL34 in order to check it
Damn, this Bugera has been purchased new from the store in Germany...
I'd have to buy set of EL34 in order to check it
Damn, this Bugera has been purchased new from the store in Germany...
Phantasmagoria
watch where you point that sabre
Re: Bugera 333xl issue. Please help
Weird. Maybe it has something to do with the "Infinium" thing malfunctioning? Sounds like digital/electronic noise.
The store probably has a return policy & Bugera have a 3 yr warranty.. :bigthumb:
Weird. Maybe it has something to do with the "Infinium" thing malfunctioning? Sounds like digital/electronic noise.
The store probably has a return policy & Bugera have a 3 yr warranty.. :bigthumb:
Last edited:
Re: Bugera 333xl issue. Please help
Should the led indicators be blinking when there is a fault or in normal operation as well?
I didn't get if you tried out new preamp tubes in there. It appears the three of them are hard to access with your hands without removing two of the power tubes or the whole chassis out of the box. Anyways, the fx loop is gonna be noisy since its part of the preamp section and if its tube buffered, if there ia a problem with a preamp tube up front of it or the one buffering it. If you remove all preamp tubes except the phase inverter tube, do you still get noise? And i can't tell from pics if that amp has a rectifier tube, placed as the small one next to the power tubes in line.
Should the led indicators be blinking when there is a fault or in normal operation as well?
Last edited:
IKSLIM
New member
Re: Bugera 333xl issue. Please help
Hank-, thank you for communication.
I have 3 12AX7 tubes and i tried to replace all the preamp tubes, rotating one by one. The preamp is clean.
All 4 indicators for PowerTubes health not lit, not blink. Unfortunately I haven't got any EL34 tubes to replace.
But I tried to isolate PorerAmpSection by sending signal from the Bugera direct from FX-Send output:
(Guitar Input >> FX Send) while PowerOutput is loaded to speaker-cabinet, BUT MasterVolume (PowerSection) set to 0. While it is set to zero, the signal from FX-Send is clear, rich and massive via all 3 channels at any drive value.
But, when I rise MasterVolume just a little, the signal from FX-Send destroyed by positive-feedback. More rise MasterVolume >> more positive-feedback. Thus, I’m assume, preamps are OK, but PowerSection has impact on preamp with positive-feedback.
Hank-, thank you for communication.
I have 3 12AX7 tubes and i tried to replace all the preamp tubes, rotating one by one. The preamp is clean.
All 4 indicators for PowerTubes health not lit, not blink. Unfortunately I haven't got any EL34 tubes to replace.
But I tried to isolate PorerAmpSection by sending signal from the Bugera direct from FX-Send output:
(Guitar Input >> FX Send) while PowerOutput is loaded to speaker-cabinet, BUT MasterVolume (PowerSection) set to 0. While it is set to zero, the signal from FX-Send is clear, rich and massive via all 3 channels at any drive value.
But, when I rise MasterVolume just a little, the signal from FX-Send destroyed by positive-feedback. More rise MasterVolume >> more positive-feedback. Thus, I’m assume, preamps are OK, but PowerSection has impact on preamp with positive-feedback.
Re: Bugera 333xl issue. Please help
I think its best to take it to a tech to get the led indication workig again. That seems to be a common problem with the infininum tech. Its good to have spare tubes around, i still kept the stock stuff that came in my amp, helps with troubleshooting but i wouldn't risk it with a freshly bought quad set of power tubes.
Looking at pics online of the inside of that amp, it appears the tube sockets are board mounted. Take extra care with these when changing tubes, solder pads may break at the board if you move it around to much when yanking a tube out.
Hope you get it working right again soon
I think its best to take it to a tech to get the led indication workig again. That seems to be a common problem with the infininum tech. Its good to have spare tubes around, i still kept the stock stuff that came in my amp, helps with troubleshooting but i wouldn't risk it with a freshly bought quad set of power tubes.
Looking at pics online of the inside of that amp, it appears the tube sockets are board mounted. Take extra care with these when changing tubes, solder pads may break at the board if you move it around to much when yanking a tube out.
Hope you get it working right again soon
IKSLIM
New member
Re: Bugera 333xl issue. Please help
Solved.
The issue has been solved by replacing 4 power tubes. Probably the parcel has been dropped really hard during shipping from Germany to Moscow. Fortunately factory packaging has good layer of foam. That's how a new device getting older... Thank you PostService....
Hank-, thank you for communication. Have a very proactive day!
Solved.
The issue has been solved by replacing 4 power tubes. Probably the parcel has been dropped really hard during shipping from Germany to Moscow. Fortunately factory packaging has good layer of foam. That's how a new device getting older... Thank you PostService....
Hank-, thank you for communication. Have a very proactive day!
- Status
