Bogner 20th XTC hums

[smdb]

I posted this in the Bogner section but this gets more views so..
My 20th XTC has started to hum fairly loud when I turn the amp on from standby, the hum is coming out of the speakers. You cannot hear the hum when the amp is on the standby position. It's fairly loud and bums me out!! Any suggestions on what it could be? I have tried different outlets and power chords, speaker cabs.... still hums.

 

[jkdsteve]

New power tubes....seriously when they start to fail/go out of bias range, this can happen.

 

[glip22]

Did you replace tubes? Could be a power or pretube. Thats what it sounds like. If you do need help let me know. You are still under warranty. I will call the dealer and work it out where the amp will ship from them to Bogner under my name for repair. You could drop it off to them since you are close. They will charge freight maybe only one way. Let me know but I would start with tubes since it happened out of nowhere. Hopefully thats what it is.

 

[JTyson]

New power tubes....seriously when they start to fail/go out of bias range, this can happen.

This ^
I had some that were seriously out of range, they started humming quite a bit, but still worked

 

[smdb]

Did you replace tubes? Could be a power or pretube. Thats what it sounds like. If you do need help let me know. You are still under warranty. I will call the dealer and work it out where the amp will ship from them to Bogner under my name for repair. You could drop it off to them since you are close. They will charge freight maybe only one way. Let me know but I would start with tubes since it happened out of nowhere. Hopefully thats what it is.

Awesome! I will try and swap tubes today and see what happens. It still works fine and has plenty of power, just humming loud as hell.
Whats the bias range for el-34?

Thanks guys!

 

[glip22]

Did you replace tubes? Could be a power or pretube. Thats what it sounds like. If you do need help let me know. You are still under warranty. I will call the dealer and work it out where the amp will ship from them to Bogner under my name for repair. You could drop it off to them since you are close. They will charge freight maybe only one way. Let me know but I would start with tubes since it happened out of nowhere. Hopefully thats what it is.

Awesome! I will try and swap tubes today and see what happens. It still works fine and has plenty of power, just humming loud as hell.
Whats the bias range for el-34?

Thanks guys!

I wouldn't bias any higher than 31ma on the hottest tube in that amp at 510 pv.

 

[smdb]

Did you replace tubes? Could be a power or pretube. Thats what it sounds like. If you do need help let me know. You are still under warranty. I will call the dealer and work it out where the amp will ship from them to Bogner under my name for repair. You could drop it off to them since you are close. They will charge freight maybe only one way. Let me know but I would start with tubes since it happened out of nowhere. Hopefully thats what it is.

Awesome! I will try and swap tubes today and see what happens. It still works fine and has plenty of power, just humming loud as hell.
Whats the bias range for el-34?

Thanks guys!

I wouldn't bias any higher than 31ma on the hottest tube in that amp at 510 pv.

I think it is a bad tube... Thank God! Gary, didn't you tell me you had tried the nos seimens 6ca7 tubes in the XTC? Those tubes cannot handle the plate voltage, can they?

 

[glip22]

Did you replace tubes? Could be a power or pretube. Thats what it sounds like. If you do need help let me know. You are still under warranty. I will call the dealer and work it out where the amp will ship from them to Bogner under my name for repair. You could drop it off to them since you are close. They will charge freight maybe only one way. Let me know but I would start with tubes since it happened out of nowhere. Hopefully thats what it is.

Awesome! I will try and swap tubes today and see what happens. It still works fine and has plenty of power, just humming loud as hell.
Whats the bias range for el-34?

Thanks guys!

I wouldn't bias any higher than 31ma on the hottest tube in that amp at 510 pv.

I think it is a bad tube... Thank God! Gary, didn't you tell me you had tried the nos seimens 6ca7 tubes in the XTC? Those tubes cannot handle the plate voltage, can they?

No, never ever would have put them in this amp. I tried the Gold Lion KT77 which handle more screen current and pv than el34's.

 

[smdb]

Did you replace tubes? Could be a power or pretube. Thats what it sounds like. If you do need help let me know. You are still under warranty. I will call the dealer and work it out where the amp will ship from them to Bogner under my name for repair. You could drop it off to them since you are close. They will charge freight maybe only one way. Let me know but I would start with tubes since it happened out of nowhere. Hopefully thats what it is.

Awesome! I will try and swap tubes today and see what happens. It still works fine and has plenty of power, just humming loud as hell.
Whats the bias range for el-34?

Thanks guys!

I wouldn't bias any higher than 31ma on the hottest tube in that amp at 510 pv.

I think it is a bad tube... Thank God! Gary, didn't you tell me you had tried the nos seimens 6ca7 tubes in the XTC? Those tubes cannot handle the plate voltage, can they?

No, never ever would have put them in this amp. I tried the Gold Lion KT77 which handle more screen current and pv than el34's.

Is that because of the plate voltage? Maybe I am just remembering you saying don't use them.
What bias setting did you use for kt77's?

 

[glip22]

Did you replace tubes? Could be a power or pretube. Thats what it sounds like. If you do need help let me know. You are still under warranty. I will call the dealer and work it out where the amp will ship from them to Bogner under my name for repair. You could drop it off to them since you are close. They will charge freight maybe only one way. Let me know but I would start with tubes since it happened out of nowhere. Hopefully thats what it is.

Awesome! I will try and swap tubes today and see what happens. It still works fine and has plenty of power, just humming loud as hell.
Whats the bias range for el-34?

Thanks guys!

I wouldn't bias any higher than 31ma on the hottest tube in that amp at 510 pv.

I think it is a bad tube... Thank God! Gary, didn't you tell me you had tried the nos seimens 6ca7 tubes in the XTC? Those tubes cannot handle the plate voltage, can they?

No, never ever would have put them in this amp. I tried the Gold Lion KT77 which handle more screen current and pv than el34's.

Is that because of the plate voltage? Maybe I am just remembering you saying don't use them.
What bias setting did you use for kt77's?

Same for the 77's. The PV is high in this head. The screen current is what you have to look out for. Many guys use the Siemens with no issues, but I would rather be safe than sorry. I don't like to put that much trust in my HT fuse. Its failed me before. I took out my OT in two different heads because of tubes arcing. This was a good while ago in different amps.

 

[smdb]

Thanks. Gary.
I am back up and running hum free again! I just blasted the crap out of the amp and it's sounding good again.
Steve

 

[glip22]

Thanks. Gary.
I am back up and running hum free again! I just blasted the crap out of the amp and it's sounding good again.
Steve

 

[smdb]

My ears are ringing bad!!

 

[Ventura]

Ain't it just a thing o' beauty....

Hope you're diggin' life, I responded on the Boggy thread, but glad to see it's worked out

Mo

 

[glip22]

My ears are ringing bad!!

Did you say something That will teach you to post "Not Again" about me. Yesterday was one of those weird days where things were happening strange. I told someone to watch out for something that would almost be impossible to happen and it happened. He called me up like WTF . I was on the phone closing the deal on my Shiva when Jim Seavall calls me. Havn't talked to him since February. I have to call him