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Hey very basic question. I need to know why my amp is getting so super hot.
I have it running one sub and the amp is running mono.

Amplifier Type Dual Channel Kenwood KAC-7201

800 Watt and something like 240 - 250/RMS I do beleive anyway.
Bass Boost With Bass Boost
Bridgable Bridgable
Power Output
RMS Power at 2 Ohms 230 W x 2
RMS Power at 4 Ohms 150 W x 2


The sub is an alpine Type-R 1000 watt 300RMS
Alpine Type-R SWR-1241D Sub
Power Handling Capacity (Peak) : 1000W
Power Handling Capacity (RMS) : 300W

The amp is not set to high gain yet as the sub is not worked in yet. The only thing I can think of is that the sub is ready for more gain and its pushing the amp to give it to it...
by the looks of it, you have the sub hooked up 4ohms?? You amp only runs 150rms on a 300 w sub...depends on how much you let it pound? Might wanna gte a better amp, better heatsink, or a built in fan...
Amp has a good heat sync.... And its got a fan built in.

Also My Premier was a 4ohm sub running the same. Only diff is the Premier was an 800 watt like 250 RMS and this is a 1000 watt with 300 RMS and this sub is duel voice coil.
is it a 4 or 2 channel amp...

do you have both channels bridged to the sub.. ie one input to the sub. (sub bridged inside the box)

or is it one Voice coil per amp channel...

more info is needed.
Its a 2 channel amp
Running the AMP as 1 channel. Left + Right - in mono mode
And yes 1 input onto the box

We connected the voice coil in the box. My buddie did it so Im not sure how he did it.

check your impedance... your amp might not like to be bridged to 2 ohm.
Here... Full speqs on the amp.
Kenwood KAC-7201

Amplifier Type Dual Channel

Bass Boost With Bass Boost

Bridgable Bridgable
Power Output
RMS Power at 2 Ohms 230 W x 2
RMS Power at 4 Ohms 150 W x 2
Performance
Frequency Response 20 Hz - 20000 Hz
Low - Pass Frequency 50 Hz - 200 Hz
Signal to Noise Ratio 100 dB
Bass Boost Frequency 90 Hz
THD at Rated RMS Power .08 %
Dimensions
Width 11.63 in.
Depth 8.69 in.
Height 2.38 in.
Other Features
Input Voltage 14.4 volt
MOSFET amp Yes
3 Way Ready Yes
How hot is hot? The only spec on the sub that is crucial here is the impedence. If the sub is 4 ohm and the amp is bridgeablke to that then you are ok. All the wattage figures are not as important as long as the the RMS power of the amp is not exceeding that of the sub. The amp if too hot should shut off and go into protect mode. Remember the heat sink is there to absorb heat so it will get hot. Contact Kenwood or a dealer and they will be able to tell you the temp at whcih the amp will shut it self down. My Phoenix Gold Heat sink is warm just from being in the car when its 35 degrees outside. Most amps will run hot to the touch especially in this weather even after a short burst of play.

David
Like after an hour it will happly burn my finger if I touch the silver part of the casing.
Its never shut down and gone into protect mode but Im just a little concerend about it.


Basicly what Im thinking of doing it Raising the amp up off my seat a little. Get two peices of wood. Paint em and put some finish up them and put em between the seat and amp. Give it about an inch between the seat and amp... Should increase the cool of by quite a bit for the amp.


P.S Specs on the SUB
Alpine Type-R SWR-1241D Sub Duel Voice Coil.
Power Handling Capacity (Peak) : 1000W
Power Handling Capacity (RMS) : 300W
Mason,Jul 19 2005, 05:14 PM Wrote:Like after an hour it will happly burn my finger if I touch the silver part of the casing.
Its never shut down and gone into protect mode but Im just a little concerend about it.

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that can't be right. :blink:
Bah the amp has gotten hotter then that. Its not over heated if it does not go into protection mode.

What I think Ill do it lift the amp off the seat.... And if I blow the amp in a few months then I blow it... That dam amp has eaten 3 sub's so far.
Yeah rasing it will help, the more air circulation the better, but at the SPL comps the Phoenix Gold Amp is too hot to touch as well. And some amps are well above 100 degrees before protect kick in.

David
I have the same problem. My amp gets HOT HOT!!! Maybe it's the the sun that heat's it up but, would a fan make any difference?
I agree. Raising will take care of major are flow problems.
Ill have to go home and 2 peices of wood and drill them to the seat.
Then the amp to the wood.
I have a fan in it... I havnt ever had the amp shut off so Im assuming yes. It must make a diff.
Mason,Jul 19 2005, 06:52 PM Wrote:I have a fan in it... I havnt ever had the amp shut off so Im assuming yes. It must make a diff.
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OK Im going to get Spacer's and put the amp on Legs... Bout an inch tall each... Should look good... And help with heat.
Hmmm, sounds like a strange scenario...the only things I can think of is the sub's coils are not wired together properly, or the amp simply doesn't put out enough amps per ch (yes, amps current, not watts) to get your sub to respond.

I used to have a Sony Sub amp in my first car, and I blew two pairs of Bazooka tubes on it. I also had a technics receiver at home with some B&W cabinets hooked up to it...same thing...blew the 2x 8" woofers in both cabinets, at a replacement cost of about $160+ from B&W (They were old), all because of a lack of current, and the amp clipping all the time. I have a 1978 Marantz Receiver that is only 52w rms, and it blows that technics I had out of the water and then some without trying. Also, I previously had a Power Acoustik Gothic series amp before, that only put out 85-86.5w RMSx2 @ 2ohms stereo. Using that amp to drive a pair of $89 each BL series subs, a factory Focus HU, and a sealed box, I never once overheated the amp, never blew the subs, and I scored 130.2db with that setup.

Something is obviously wrong if you cooked subs with that amp already, and it gets really hot. I think the output stage of the amp might have an internal deffect...

A cheap fix would be to find a used Alpine V12 amp (if you wanna stick with Alpine) from somewhere like Cash Converters. I've seen ones in good shape at the store in Brantford in the past, and with a reasonable price.

Maybe some of this stuff will help...

Break out the multimeter and test the resistance on the sub!!! get back to us... sounds like somethings wired wrong.
This is the only sub that has made this amp hot.

The way Im seeing it is that sub is the most powerful sub Ive put on that amp... The amp is just under rated for the sub.

The sub pounds perfectly. And the amp never goes into protect mode.... If I turn the volume down and listen at low volumes the amp will cool off and eventually not be how. If I crank it again it will eventually get warm again.
TEST THE RESISTANCE ON THE SUB!


then we can give you a proper diagnosis.

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