I own two GK MB150S amplifiers. I think both are the second version.
Recently I've noticed a small amount of distortion coming from one of the amps, and have been turning the active/passive switch on (to active) to minimise the effect. Over the weekend, I decided to do a side by side comparison between the two amps.
It appears that the amp with the problem has a far lower output than the other. Also, I took the preamp signal from the OK amp to the power amp in of the problem amp (using the effect send and return), and by doing this, the output from the problem amp came back to being the same (or very close) the the OK amp. So it appears that the problem is in the preamp section of the problem amp.
I read on here some time back that the MB150 had a known fault with the amp section, but I've searched through the forum and can't find reference to the problem.
Do any of you guys recognise the symptoms I've described, and do you know the solution for the problem? I don't intend to fix this myself, but the more information I have to take to mu electrical guy, the better.
Recently I've noticed a small amount of distortion coming from one of the amps, and have been turning the active/passive switch on (to active) to minimise the effect. Over the weekend, I decided to do a side by side comparison between the two amps.
It appears that the amp with the problem has a far lower output than the other. Also, I took the preamp signal from the OK amp to the power amp in of the problem amp (using the effect send and return), and by doing this, the output from the problem amp came back to being the same (or very close) the the OK amp. So it appears that the problem is in the preamp section of the problem amp.
I read on here some time back that the MB150 had a known fault with the amp section, but I've searched through the forum and can't find reference to the problem.
Do any of you guys recognise the symptoms I've described, and do you know the solution for the problem? I don't intend to fix this myself, but the more information I have to take to mu electrical guy, the better.
