sub cuts out at half volume

hi i have a 12" 400w pioneer IIMP sub in the factory made box it sounds good when it works but every now and then it cuts out the amp is an 800w kenwood the gain is all the way down the bass boost is on (12db) and the lpf is set to just over 70 hz if tried the amp both bridged and mono (left channel only) it don't seem to help either way i think it works better in mono vs. bridged but i want to know why my sub cuts out ? is it my sub itself or is it the amp ! the amp always seems to run really hot but is it pushing too much to the sub that it shuts down ? the amp seems to work fine just hot but ive never had more than a 400w amp so maybe its normal ! the fan on the amp usually come on right away ! some one please help me !??

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rattles suck lets hear your system

Is your sub dvc or single? If dvc how is it wired? What size power wire are you running?

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i have 4ga power wire to the amp it splits into 2 8ga so i can run a second amp and i grounded it with 8ga  wire and i have 12 ga to the sub from the amp but i think i have it somewhat figured out now i took the sub out of the box and found out that its a SVC and my ohmeter read 1.2 ohms for the voice coil so i need to run it at 4ohm with my amp ? is there any type of resistor i can buy to wire in series with the sub so it will be at 4 ohms and if so what resistance should i buy ? 2.8 ?? or as close to it? thanks for the help !!! 

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rattles suck lets hear your system

You can either get another 2ohm sub & wire them in series or get rid of that sub and buy a sub that is 4ohm.

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is there any way to keep my sub and wire a resistor in series with it ? i cant afford to buy a different sub !

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rattles suck lets hear your system

Forget the resistor- it's not the right idea.  A resistor will just waste a bunch of power and get really hot and fry.  Your problem is an equipment mismatch.  You're trying to push a 2 ohm single voice coil sub with a stereo amp.  Most stereo amps will handle 2 ohms per channel, or 4 ohms bridged.  The ideal solution is to get a mono (single channel) amp that's designed to push subwoofers or switch drivers.  However you can just hook up your sub to one channel for now until you can upgrade.

Do a search on this forum on how to set gains.  Start with your bass boost off.

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My ex once told me I have a perfect face for radio.

thanks , my amp is a kenwood not sure if i stated that but its 800w i am only running one channel and i have the switch on the side set to "mono" which reads left channel only and thats where my speaker is hooked up ! but should i turn that switch to stereo b/c im not sure that with that switch on mono it can handle 2 ohms but i was told it could handle 2 ohms per channel stereo! 

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rattles suck lets hear your system

yes two ohms STEREO not MONO...so why would you have the switch at mono?

yes but mono is only the left channel and when your in stereo both the left and right channels can handle 2 ohms but if your bridged it can only handle 4 ohms but its not bridged im only using the left channel the mono channel and the switch is at mono! but can that switch matter ? i mean as long as its not bridged then it can handle 2 ohms right ? but is my woofer even 2 ohm ? my ohmeter reads 1.2 ohms at the woofers terminals ! so is it a 1 ohm or a 2 ohm woofer ?

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rattles suck lets hear your system

ohmeters are off by a lil bit so you are prolly at two ohms.

You said that when the switch is at mono the amp only sees the left channel only...2 ohms stereo and 4 ohms MONO.

I'm not sure about that though cuz you have not posted the amp model...only stating that it is a 800 watt kenwood.

If your amp is stereo & your sub is 2ohm you need to leave the setting on the amp on stereo. If you put it on mono your amp is seeing 2ohm's mono.

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furlier...exactly what i was meaning.