Stereo gurus. need help
 

I have a kicker ZX.850.4 and I'm running 8ea polk audio 6.5" 4ohm speakers. It plays at normal volume, but when i crank it up the amp goes into protection mode. Brand new amp. Brand new speakers. What can it be? Are speakers a true 4ohm? If not, is it possible that the speakers are dropping the amp below 2ohms?

Sounds like they are either
1) wired to the wrong ohms
2) amp is under powered
3) power and ground wire to small
4) ground wire not grounded well

what model are the polks? i know they have some components that are only 3ohm which is fine until your run more in parallel.

if possible i would unhook 4 of the speakers & just run the amp in normal 4ch mode. if the problem still occurs when you crank it up its probably the amp wiring (assuming since amp is new). if everything is fine, then more than likely the speakers are putting a load greater than 2 ohms.

Kyboy is right

The other thing I would do is out a Volt meter on the power an make sure the voltage is above 12v when you turn the volume up

These are all the right answers. If I had to guess, I would look at the Ohms for your speaker load and how you have them wired. If you are running it at 2 ohms or less, your amp is overloading and tripping into protection mode.

Overheating

Overheating is generally caused by the same issues I listed above. I run 6 speakers and 2 subs off 2 amps inside a compartment with no vents and black carpet and they have never ever overheated. I sometimes prop the door open to the little compartment just to make myself feel good. But overheating is generally caused by overpowering and amp by overworking it. I run all my amps at 25-40% and nothing more. If I was building a show boat I would blow them all the way out but I am looking for longevity.

1) wired to the wrong ohms maybe
2) amp is under powered how is an amp under powered?
3) power and ground wire to small it has a huge freakin wire abt 3/4"..lol sorry dont know gage
4) ground wire not grounded well dont think so bc sometimes it will jam then just cut off. its cut off while sitting on the trailer

here are the speakers i have

http://www.sonicelectronix.com/item_...o+MM651UM.html

the amp gets hot but not hot enough that you cant keep your hand on it. It has also cuts out within 2min of playing. sometimes it will rock for 2min and sometimes for 2 hours. when it cuts out i lower the volume and it comes right back on..

Amp is underpowered for the speaker set up is what that means. That sounds like your issue since turning it down fixes it. Check to see how you have the speakers wired and give us details of the amp

get a meter and test the ohms at speaker leads where they come into the amp. also check and make sure the amp gains are not cranked all out and maxed.

I think Kyboy is on the right track, it is more thant likely one of the above items.

Amps can easily be underpowered for the load they are seeing. As a matter of fact it is much better to have an amp that is overpowered (truly more power than you need, not just over-rated) than to have an amp that is under powered. That amp will have to work harder to produce the desired SPL and will more than likely start clipping. This is where the waveform flattens out because the amp is not stable at the required current. This causes distrtion and serious heat issues.

Sounds like this could be your problem and it could be as the others have noted directly related to how your 8(?) 4 ohm speakers are wired to the amp.

Also, you are on the right track re: the ground issue and the amp shutting off quickly. If it were a ground problem it would probably be a softer clip, for lack of better terms. However in a boat the ground issue would have nothing to do with whether the boat is on the trailer. It either has a good ground or not.

here is the amp and speakers im running.

http://www.sonicelectronix.com/item_...r+ZX850.4.html
http://www.sonicelectronix.com/item_...o+MM651UM.html

so this is what i done last night

ohm on each speaker lead is 3.8ohm
if i wire 2 speakers parallel it bounces from 1.9 to 2

fyi my radio volume maxes at 34 and the amp gain is at a quarter

I hooked 4 speakers to its own channel and it played fine to 34 as soon as i changed one channel to 2 speakers wired parallel it cut out. If i lowered the volume to 25 it will come back on and play. but on high pitch sounds at volume 25 it cuts back out and 3-4 seconds pass and it comes back

did i confuse you?

The ohm reading is a dc resistance measurement. The impedance can be much different, and it always varies with frequency. That is what the amp really sees.

Either way, sounds like the amp is not stable at the lower impedance you are trying to drive. Did you check each speaker ohm reading at the amp?

Why you say high pitch, you mean volume (spl) or bass, or highs?

Just for fun, raise your low pass filter up (high frequency, meaning less low frequency to the speakers) and see what happens.

You got 4 ohm speakers and a 4 ohm amp. Put each speaker on its own channel and you should be fine. There is no reason to parallell them you have plenty of power and don't need to lower to 2 ohm.

high pass filter is on and eq is set to cut out all bass

kyboy
I have 8 speakers. If i run 4 speakers on its own channel then i have 4 speakers not hooked up

this stereo is really kicking my a$$

the worse is when the girls are booty shaking and just when the party is about to get started the stereo cuts out and everyone looks at me like WTF

You can try turning your gain up on the amp. It probably won't make a difference but it is worth a shot.

It seems to me your amp isn't liking the 2 ohm load. I'm pretty sure the real solution to this is to add another 4 channel amp to the system.

Yep...you need a amp with more channels. Unplug four speakers for now and only run 4. It will sound better and work better. You are straining the amp with the 2ohm load.

Just because kicker said it is stable at 2 ohm doesn't mean it is.

Get another four channel amp.

I just looked at the amp spec, you have the high pass set to 200hz?

At this point doubt it will help, you still seem to need another four channel amp.

thats what im doing and im in the process of getting another amp

thanks

Does this only happen when you are on battery power? I'm betting you can crank it up fine when the motor's running?

If so, what batteries do you have? If you can't draw enough current the amp goes into protect, typically when the voltage drops below 12.

You can then add another deep cycle battery, or get a class D amp which draws less power than your Kicker. I don't know if Kicker's are current hogs and inefficient (like JL amps), but this could definitely be the problem.

i have 4 batteries and it happens at both times...i guess the amp cant handle the 2 ohm load

Sounds like it then. If everything is wired right and grounds are good, that is the likely problem.

Weird though, as the kicker amp should do 2 ohms if it's rated for it.

same thing i thought and I didnt think i was pushing the amp to the extreme at all

Did you check out the Polk amps ? I run my system with the 5 channel PA 1100.5 class D amp. Lots of power but on the large side. It's not a marine amp, but as long as you have a dry place to mount it you'll have no problems. Other than speakers, I've always used car audio for my boats
Sounds like you need more amp like everyone says.
Good luck, BC