I got my amp in 2009. It blew a transformer so I sent it to a authorized tech to fix while he had it he modded it but I don't know what he did, I trusted him. I got it back and I didn't like the sound so I just shelved it and used my other amps. I moved to Ca and after the move I fired up the overtone and it blew another tranny. I had it fixed here in Redding, Ca. and switched power tubes..I was using el34's now I am using 6l6's and am going to get some winged C 6l6gc's. I have no idea why I blew two tranny's the tech here who fixed it thinks there was a short. He broke my face plate and told me that someone else tightened the on light bezel too tight. I have had it with all these effing techs. Can you tell I am mad ha ha. Okay the tranny's never should have failed it is just my bad luck and that is not my point, my point is I have never heard my amp really so I don't know how it sounds. I am going to try a third time to find a tech who knows dumble amps and see if I can get it running  how I want which is to experience the rich tone this amp is famous for. I could care less whether I sound like Robben Ford or, Larry Carlton or anyone else you care to name. I don't give a shit I just want what this amp is capable of or as close as you can come. That first tech took out the negative feedback loop without even asking me. So here I sit with no real idea where to head because I don't know other than the feedback loop what the first tech did and i am trying to find a tech around here who knows these amps. I am electrically illiterate so I am at the mercy of these so called techs and my point in writing all this is to get some feedback from some of you and get a plan that actually will solve the problem and get me an amp that sounds good. I want to point out that this has nothing to do with Nik or ceriatone. He has treated me straight up. Anyway, sorry to be a bitch, I am just frustrated..so any ideas ha ha..and thanks in advance

Thanks Rane. Coincidense Thanks Rane I will call him. There is a guy in Chico that might know dumbles too. Funny thing I am going to Los Gatos to see my ex mother in law..ha  ha, made myself  laugh thinking about mother in law jokes. She turned into a friend and in this life we can't be choosy where they come from, just grateful  that they appear.

 Not sure when I am going but soon for sure she is ninety and I am 71, an old grandpa. I want to do this fairly soon. Thanks for the reply.

Ha ha thanks for making me laugh with the hairdresser analogy true dat. I talked to the amp guy in San Jose mentioned above and he knows dumble..just sent him some picks of amp guts. Take care @71 you figure out, or I did anyhow, what you should know when you are young, life is short then you die and go for it. Life is meant to be lived, there are no rules for what age you need to be to do or not do things. Just be kind and try not to hurt anyone.

Sorry to be so pissed I apologize

Thanks Hywelg you are probably right, circles. The bias thing is a mystery though, but I will call the tube guy and see what he has to say. I am in contact with Bill at Sebago already. I kind of know what I want the amp to do even if I suck as a guitar player, I have a good ear. Thanks for the input. We have both been around here for awhile so it really is good to see that you are still here as I said before. I will be getting another amp either the HRM or the 70's voiced DT50 from Bill..so I have a rough idea how I want things to sound.This will be the last amp I buy I hope ha ha.

I understand all that, it is making me a better player and a lead channel is what I want, I am not trying to play rhythm on the overdrive. The clean channel is just not quite there yet. I will take it to Bill at Sebago and raise the heater wire and replace some stuff on the board,

Just out of curiosity what or how is you amp eq'd. You have the same as me I think an OTS non HRM
Thanks for the great feedback Hywelg I appreciate what you are telling me. I wont get hasty about buying another one if I can get the sound I am after which is always at its base a Dumble sound. Sorry to ramble on. I need a starting point that is why I ask you about your EQ. Damn smoking, quitting my little buddies aka cigarettes is really my problem right now ha ha.

if you are in the Sacramento area ever let me know I would be happy to give your amp a thorough checkup.
Regarding your HRM thread I would suggest you be sure to get this OTS running correctly first before considering another D-style amp. The differences between HRM and non-hrm are more subtle than you may think!

Todd

Not for nothin, but it sounds like the knob you are turning for the OD trim is actually the Bias pot. the Bias pot usually under the circuit board (the bulk of it) the shaft and knob usually pokes out the bottom. on most dumbles and clones, The OD trim will be a small trimpot basically sitting over V2 and its circuitry with the adjustment slot facing horizontal towards the front or rear of the chassis. There should also be another trimpot over V3 for the PI trim.

Agan, this could be the case and having the Bias too low can cause crossover distorion, and too high can make the amp muddy and undefined, and could burn the tubes up, shorting them out and causing your transformer woes as well.

Again this is just a theory, and i wouldn't be able to prove it without pics of what ya got.

Keep rockin, man! My dad is 72, still works a full time job and rocks as well!

Hope this helps!

Gregg