Temporary GK MB210 death ??

GRAHAM SG1 · #1 03-30-2011, 04:42 PM

I had my amp cut out on me at rehearsal this evening, I was driving it pretty hard with my MBE115 connected when it just shut off for about 30 seconds then came back on again and was perfect for the rest of the evening, is this some kind of circuit protection built in, I know that there were no leads pulled out or anything like that, maybe a mains power surge ??
This is the first time this has happened .

RickenBoogie · #2 03-30-2011, 05:19 PM

Yes, most likely a protection circuit, and yes, you were probably pushing it too hard, and that's why it "protected" itself.

GRAHAM SG1 · #3 03-31-2011, 02:05 AM

The amp was nowhere near its limits though, the gain, boost and master were all on half with the EQ all around half too, I did up the bass EQ on my Ibanez active bass though and that really thumps when it gets over the mid point

philter25 · #4 03-31-2011, 06:32 AM

Im not electronics engineer, but I dont believe the amp needs to be near its limits for the protection to be activated.

Say you are running an active bass with a hot signal through a preamp putting out a hot signal. If you turn up the EQ on your bass, even though the gain might not be near its limits on the amp, the signal coming in might be enough to activate the protection.

billfitzmaurice · #5 03-31-2011, 06:46 AM

Quote:

Originally Posted by GRAHAM SG1

The amp was nowhere near its limits though, the gain, boost and master were all on half with the EQ all around half too,

The position of the knobs bears no direct relationship to the power, and therefore heat, being produced.

Quote:

I did up the bass EQ on my Ibanez active bass though and that really thumps when it gets over the mid point

This is a classic example of a Youngman. I went to the doctor, told him my arm hurts when I do that. He said :"Don't do that".

Yerf Dog · #6 03-31-2011, 06:49 AM

I had it happen once on my MB212. Pushing too hard... Don't do that.

sevenyearsdown · #7 03-31-2011, 07:06 AM

they don't have a fan?

GRAHAM SG1 · #8 03-31-2011, 10:49 AM

Quote:

This is a classic example of a Youngman. I went to the doctor, told him my arm hurts when I do that. He said :"Don't do that".

I prefer to remember that line by the late great Tommy Cooper

I always thought that by increasing the output level (turning the knobs) increases the current going through the amp which in turn generates more heat ?