New Amp Goes Into Protection Mode

loudandheard · Post by **loudandheard** » Sun Aug 28, 2005 8:17 pm

I recently purchased an MB QUART RAA4200 which is a 100 watts X 4 channels. I was using the amp to power my MB QUART components by biamping the crossover. This is the only amp in the car right now, so I have the power wire and the ground wire coming off the cap. The cap is grounded to the chasis in the trunk and the power wire is connected directly to the battery. My friend suggested that I ground the amp to the chassis and not the cap it self. I have powered multiple amps off the cap before in that manner and never had a problem before.

The amp plays only the left side speakers at the minimum gain. I can turn the deck completely up and no clipping and no protection mode only with the left side speakers. When I turn the gain up with just the right side speakers it goes into protection mode. Now when I connect the right side speakers to the amp it clips in and out of protection mode with and with out the right side connected. I used two, one female connection with two male ends to connect the front channels to the 4 channel amps. So for the first two channels I have the midbases connected and the last two channels connected to the tweeters. So it's weird that only the right side works and not the left. I will need to check everything more thorough, but it got dark.

I need to check the battery connection one more time, but what do you think the problem can be? I'm worried it could be the amp it self, but it's brand new.

Ryan from Ohio · Post by **Ryan from Ohio** » Mon Aug 29, 2005 6:08 am

You shouldnt be grounding to the cap like that. Its not common or good practice, but I dont think its your real problem. You should ground the amp directly to a chassis ground- period.

Sounds like the amp may be bad.

loudandheard · Post by **loudandheard** » Mon Aug 29, 2005 4:34 pm

Ok, so I tired another amp and this time it's grounded to the chassis. Again the right side works and this time I can put the gain as high as I want on the right side, but now when I connect the left side the amp goes into protection mode. I have different tweeters on the right side than I do on the left side, I'm not sure if that has anything to do with it. Is the amp bad too, it's new also.

Mon Aug 29, 2005 4:45 pm

have you tried hooking up a different set of speakers to the left side?

Why are the tweeters on the left side different?
Maybe you have some bad tweeters that are shorting out your output. Causing it to go into protection mode.

loudandheard · Post by **loudandheard** » Mon Aug 29, 2005 4:48 pm

My original tweeter from the component set stopped working on the right so I replaced it with another, I didn't need to replace the other one, I'm going to try placing the left side speakers on the right and see what happens and I'll check the speakers as well.

Ryan from Ohio · Post by **Ryan from Ohio** » Mon Aug 29, 2005 5:37 pm

Whatever speakers you have on the amplifier are messed up.

Put a DMM on it and weed out the problem. Unhook them speakers and DONT try to use them!

loudandheard · Post by **loudandheard** » Mon Aug 29, 2005 5:47 pm

Digital multi meter right?

audiofreak12 · Post by **audiofreak12** » Mon Aug 29, 2005 6:19 pm