Originally Posted by bajansen
I have an older (outside of warranty) GK MB115, that has suddenly gone belly-up.
When powered on, the LED switches to purple/pink and will not go blue.
When powering off the amp, it will go to blue before completely shutting down and you can hear a very brief blast of tone from the bass guitar?
Can anyone shed some light? Do I need to replace the power amp module?
I had the EXACT same issue with mine and it was also out of warranty. Local GK dealer did not have a clue and offered to send it into GK. However with it being out of warranty and shipping from Canada it just was not worth it. The shipping alone would have blown the repair budget.
A very good local tech was able to trace the fault to the preamp board, but was unable to determine which specific component on the board was causing the issue. The cost of a replacement preamp board etc. was prohibitive, so I just had him convert the unit into a cabinet and was able to sell it for a reasonable price as a cab. With that money I bought TWO used Traynor combos that will probably last me forever. One thing I will say for GK is that their resale value is pretty decent LOL!
BTW, I also had the exact same issue with a GK MB200 head, however it was replaced under warranty being only a few weeks old. I sold the replacement MB200 head to buy the MB115 thinking the combo might be more reliable (not sure what I was smoking at the time...