Grandmeister died on me

I just switched on the Grandmeister this morning- it lit up, went KABOOM and then died on me. There is no light, no sound, no nothing..I hope it was just a fuse and nothing more serious since I need to gig with this amp come saturday. Can you change a fuse in these things yourself and where about in the amp does it sit? I´d be really grateful for any suggestions on what to do

Are you used to working around high voltages MatsP?

Nope. I´m not so the Grandmeister will be delivered to a friend of mine who has a amprepairing shop today...

bordonbert wrote:Are you used to working around high voltages MatsP?

Good to hear that your being practical about it MatsP. I only wanted to know before offering advice how safe it was going to be for you to open it up and poke about inside. He won't have any trouble locating the fuses. We don't have any details of the GM36 layout I'm afraid but there are other H&K amps similar which we know quite well. These show a very simple layout to follow.

If it does turn out to be a simple fuse fault the fuse values are in the manual and MUST be followed or you will have further trouble. The mains fuse is in the socket and I believe there are two PSU fuses inside on the main PCB, they are very easy to spot. The best way to contact H&K for advice if it should be needed is to get onto their Facebook page. Other people report that emails can get left for a long time! Search for H&K Product/Service and they will come up.

I have to say that it doesn't sound just like a fuse itself at fault to me. With a bang before the fuse went there surely has to be an underlying cause. No lights suggests at least the Low Voltage side of the power supply has blown its fuse. There is of course also a separate High Voltage side to the supply with its own fuse which feeds the valves. If the LT fuse has blown and the HT fuse is intact then you can expect high voltages to hang around there for a while! It is also possible that only the mains fuse itself has blown which would take down both sides of the supply.

Please let us know how your friend gets on and get back if there is anything more we can help with.

If a power tube failed and shorted internally (it happens) it could have caused what you experienced. The TSC does a damn good job but even it can only react so fast. Hope for the best case that a tube failed and blew the fuse before the power transformer. While the transformer is very easy to replace, it`s the most expensive single component in the amp if not covered under warranty. The good news is that it`s not very common for transformers to fail, and the ones in the GM36 are extra beefy for it`s size. In fact, it`s so uncommon for them to fail that when mine blew up in my Carvin amp, despite being out of warranty they hooked me up with a new one at their cost, saving me about 60%.

Should have put this up earlier. I got the Facebook search details wrong in my last post.  Search under just "Hughes & Kettner" NOT "H&K Product/Service" and look for the "Hughes & Kettner Product/Service" page in the dropdown match list which shows an angled front panel of a GM36.  (No I don't understand why Faecesbook can't locate this easily every time either!)