Hughes and Kettner Triamp MKII with one dead channel...how to troubleshoot? Or good H&K service centers/techs to mail it to?

[Locrain]

Hi, I have had a H&K Triamp MKII for a long time, maybe 12-13 years. Some time after I got it, channel 3A started to make a horrible noise, it lacks much character, just noise. Almost like a buzzing, but it is so loud as to almost completely overpower the guitar signal and makes the channel useless. The amp has stayed like that for 10 years, no better or worse. I have swapped tubes around to try and eliminate that as a cause...but it has been a long time, maybe a new set of tube all around would be a good start.

I am not an amp tech. Unfortunately, neither is anyone I know of within driving distance. So it is either to send it to one of H&Ks authorized service centers and hope they have seen the amp before, or possibly try a few more tests/parts swap myself...I obviously have no idea.

Does anyone has anywhere in the US that has serviced their H&K that seemed competent and familiar with the brand? I have an old service center list I got from repeatedly emailing H&K in Germany, but that is about all I have to go on.

Much thanks for any help.

 

[glpg80]

Does it happen if you send the preamp signal to another amp and you hear it in the other amp?

Would help you isolate whether it’s preamp or power amp related.

There’s really not much you can do on a forum. Some problems need to be solved on a bench, not online. We can speculate all day long, but in reality it’s never going to find the cause.

If it were me I’d probably look for cold solder joints.

 

[Locrain]

Does it happen if you send the preamp signal to another amp and you hear it in the other amp?

Would help you isolate whether it’s preamp or power amp related.

There’s really not much you can do on a forum. Some problems need to be solved on a bench, not online. We can speculate all day long, but in reality it’s never going to find the cause.

If it were me I’d probably look for cold solder joints.

I *think* we tried that into the poweramp section of my other Triamp MKII at the time...but I am not sure, it's been a while. Definitely a good way to figure out which section it is in, I will give that a try, thanks!