Stereo guys please help, <BR>I've got kicker 850.4 running 4 kicker 6x9's on the tower and 4 in the boat <BR>Another kicker 1000.1 running a kicker cvx 10" <BR>My problem is that with the volumn at about half way up for about a minute the highs cut out until I turn the deck down for a few seconds. The stereo shop says that I need another battery on top of the two that I already have. The other thing that they said it could be a blown speaker, but they all seem to be good. Any help would be great

I would check two things first and they will both require a volt meter. The first would be the battery voltage at the amp terminals. You want to put the black volt meter probe on the negative power connector at the amp and the red probe on the positive power connector and check the voltage. You are looking for something around 12.5 volts (If it's much lower then that, STOP and charge each battery then continue)before you turn on the stereo. Then turn on the system and turn it up to the point it cuts out and watch the battery voltage. It should drop a little bit but if it drops much below 12 volts then that could be part of your problem. Next check the speaker ohms the amp is seeing by unhooking the speaker leads from the amp (I usually do this one channel at a time, one channel being the positive and negative for a speaker or speakers). Take the volt meter and switch it to "ohms" and use a scale that will read 2-8 ohms. Then use the red probe on the positive speaker and the black on the negative and note your reading. With two average car speakers running on a single channel you will usually see about a 2-3 ohm reading. If it's much lower then that then or no reading at all, you may have a shorted wire or speaker or both. <BR> <BR>Good Luck}

scott nailed this one. <BR> <BR>I've actaully had the identical problem but one of my speaker wires had been cut and was shorting my highs out. All the apeakers were fine. you will be able to see this by testing the speaker/wire leads as Scott described.

Chris - <BR> <BR>I have this exact same amp running 4 JL M770 interior speakers and 4 Polk Momo MMC6500 tower speakers. My problem was that at 3/4 volume running for an extended amount of time, all the speakers (other than the sub) what clip out. The problems was the 2 ohm load on the KX850.4 was causing it to clip out and get too hot. Running this amp at 2 ohms for a while is very hard on it and it will heat up. I did the test that Scott eluded to and was getting 13.2V at the amp with the engine on at 2,000 rpms. <BR> <BR>I have since add a KX650.4 for the interior JL speakers and am using the KX850.4 for my new NVS Tyrant tower speakers. I have not been able to test everything because of the weather but hopefully this cures my problem. <BR> <BR>Good Luck.

Also sounds like the gains may set too high. If not a shorted speaker lead, turn the gains down a little and see if the problem continues.

Scott, <BR> Thanks for all the info. tomarrow after work I'll head to my garage and start at the beginning of your list until I find the prob. <BR>TigeMike, <BR> Gains are set on the low side already, as it seems like plenty of power. <BR> <BR> Thanks alot, as soon as I figure it out I will let you guys know. Thanks again!

Ok, 12.3 volts with stereo off <BR>11.6 when it cuts out. <BR>2.3 ohms on all the speakers. <BR> <BR>any other ideas?

Chris- 12.3 volts is a dead battery....You need to charge all your batteries. Use a good charger and charge each one by itself, overnight. So two batteries will be two nights or two chargers. <BR>Here is a chart that will help explain.... <BR>SG Volt SOC <BR>>1.265 12.66 100% <BR>>1.225 12.45 75% <BR>>1.190 12.24 50% <BR>>1.155 12.06 25% <BR>>1.120 11.89 0% <BR>> <BR>>SG is Specific Gravity <BR>>SOC is State Of Charge <BR> <BR>Running all four channels into 2 ohms also asks the amp to try to double it's power out which means that it is trying to pull twice the current from the batteries. This starts the downward spiral. Charge the batteries first and see if things get better, I bet they will. <BR> <BR>Once you fix the battery issue, the next issue you will likely encounter is the amp getting too hot and shutting down. There are two ways to really fix this problem. 1) Add more power (A second amp) 2) turn down the volume so that the amps heatsink can keep up with heat demands. Remember, it's 40-50 degrees cooler this time of year compaired to the hot summer weather so it will play significantly longer today then it will in the summer. <BR> <BR>Good Luck <BR>Scott

Chris - <BR> <BR>Were those readings taken with the engine off, idling or at an elevated RPM (say 2K)?

Tom- <BR> <BR>The readings were with the boat off. The amps never seem to really get hot. The zx850.4 seems to stay cool enough to keep your hand on it as long as you want. I will charge the batteries and see what happens. I appriciate all the help and suggestions

Great info Scott........