Question about Legacy - American II: 4 Channel 1000W American II Series LA-690 Car Audio Amplifier

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Constant thumping when i turn the level up past 45% the sub starts thumping.even with the head unit off. i have a single kicker bridged on only 2 groung is didint do that untill my girlfriend unhoocked the sub and one of the leads touched the amp and blew the fuse

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Theres most likly an open ground printed circuit trace on the Printed circuit board on the bottom. first clue is You said your girlfriend disconncted and blew the fuse. You gonna have to ytake the amp apart and totally disassemble the PCB off the rails and everything unless theres a bottom cover. It may be an obvious burn or could be hidding under the green paint of a trace?? Goos luck

Posted on Jun 07, 2006


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I have Boss ar2400 4 channel amplifire.. I had connect two 15" kicker subs in bridge circuit. When i run the system it gets overheat in half an hour and goes into the protection mode. How can i solve this...

Problem is one of four things:
  • Impedance (ohm resistance) of the speakers you are using is below the amplifier's rating for operating in bridge mode;
  • You are driving the speakers at a volume exceeding the maximum power output of the amplifier;
  • The gauge of the wires you are using to connect the amplifier to the speakers is too small;
  • The gauge of the power supply wires is too small, and/or you are not using a large enough reserve capacitor at the power input
Possible solutions:
  1. If your Kicker subs are rated at 4 Ohms, and you are using them in monoblock configuration with the speakers wired in parallel (all + terminals to the + bridge output and all - terminals to the - bridge output), try either configuring your bridge circuit in a paired bridge, where a pair of amplifier outputs are bridged, each bridged pair driving a single speaker; or if your Kicker subs are rated at 2 Ohms, use a monoblock bridge driving the speakers in series (+ bridge output to + of one speaker, - of that speaker connected to the + of the other speaker, and = of that speaker connected to - of the bridge output);
  2. Turn the amplifier output down (but this is likely NOT the issue)
  3. Use speaker wire that is no smaller than 8 gauge for your application. 4 or 2 gauge wire would be slightly better but not worth the additional expense;
  4. Your power supply wire should be equal in size or larger than your speaker connector wire. Use no smaller than 8 gauge for your application. Also, use a capacitor no smaller than 2 Farads wired across the power supply input to the amplifier to compensate for pulse surges and car power dips. For your application a large capacitor will work better than an auxiliary battery or gel cell.

May 26, 2014 | Car Audio & Video

1 Answer

2 channel amp with 2 Kicker Cvrs 15"

Assuming the amplifier is 2 ohm mono stable... the amplifier is bridgeable... and the subwoofers are Single 4 Ohm Voicecoils, You would wire them as follows....

Both + on Both subs to the + bridged terminal on the amplifier.
Both - on Both subs to the - bridged terminal on the amplifier.

This will net a 2 ohm mono load for your amplifier.

If you have something different - let me know... and I will give you the proper wiring for what you have.

Thanks for using FixYa - a FixYa rating is appreciated for answering your FREE question.

Jun 10, 2009 | Kicker CVR12 Car Subwoofer

2 Answers

I need to know how to bridge a a 4 ohm 15 inch sub down to1or2ohm

Hello solo7908,

With a single 4ohm DVC sub there are only two possible wiring solutions, parallel the voice coils for a final 2ohm load or series the voice coils for an 8ohm load. In your case, you want to wire them in parallel, both positives and both negatives connected to the amp terminals.

Here are the diagrams: (-) to (-) and then to the amp - (+) to (+) and then to the amp. Impedance = 2ohms.

Hope this helps.

Jun 06, 2009 | Kicker CompVR 12" Subwoofers/Enclosure...

1 Answer

Wiring my 2 L7 with a kicker 1000times1

Run the subs in series then bridge the amp. So run the normal + to - to the one sub then hook up a spare wire (not connected to the amp) to the same + and - connections. Then run the spare wire to the + and - of the other sub. This will tie the 2 together so you can bridge the ampfor more power instead of using 2 seperate channels.

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2 Answers

Pioneer deck kicker sub 2 mossfit amps

scanman84: i would recommend using the 2 channel 300W amp to drive the dual voice coil alone. i wouldn't combine the single channel amp with the 2 channel. you can't tie the 2 channel outputs together & use that on 1 voice & attach the single channel amp to the other, plus there could be slight differences in amplification & timing which, could cause the sub to have minimal movement or cause a canceling effect which would reduce the spl, sound pressure level. if you need more volume use the lowest impedence speaker recommended by the amp's mfg & if you need serious volume, go with a higher output single 2 channel amp. just make sure you have sufficient wire size to handle high powered amps. example, 8awg wire is rated for 73 amps. also make sure the amp is well grounded with nut & bolt connections to the frame & that there is good ventilation.


Jan 06, 2009 | Car Audio & Video

1 Answer

Knocking noise with my kicker compvr 15"

comp VR 15s are rated @ 500W RMS 1000Peak.
The lanzar vibe amplifier is 2 x 600W RMS at 4 OHMS 2 x 1200W MAX at 4 OHMS 1 x 2400W MAX at 4 OHMS Bridged 2 x 1000W at 2 OHMS RMS.
Your subs are single 4 ohm subs.
If your subs are wired stereo, they both are seeing 600W. (more than the rated RMS)
Chances are, you have them wired parallel to a 2 ohm mono load - of which that amplifier is not rated. In theory, it will produce about 2000W @ 2 ohm mono for a short period of time.
Your amplifier is too powerful for your subs. Turn down the gain setting to 3/4 or purchase better subs. Also be sur the subs are inthe proper enclosure. It sounds as if they are excurting past their linear x-max and colliding with the rear bump plate. This will cause damage down the road if left as is.

Nov 26, 2008 | Kicker CompVR 05CVR84 Car Subwoofer

1 Answer

2006 12" Kicker L7 4 ohm

first whats the range in terms of WATTS that your 12" sub can handle in 4 OHMS ? second , lets check the AMP , POWER ACOUSTIK 1800 WATTS , Now thats a lot of power to drive a single 12" sub speaker . your amp is 1800 watts , per channel is around 500 watts , if BRIDGE thats around 1600 watts rms for ONE channel , if your sub can handle that kind of wattage fine , but it will not blow the amp , what it does is shuts down , some kind of protection mode , it will come back on after a minute or so. I suggest to use one channel in stereo mode , or purchase another sub to use the other channel. i hope this helps AJ

May 06, 2008 | Kicker 06ZX750.1 Car Audio Amplifier

1 Answer

Annoying thump from two 15" kicker comps powered by a lanzar vibe 266 amp

It sounds like it may be oscillating. This can be caused by a broken ground in the signal line. You need to check the RCA shield on the head unit.You'll need an ohm meter. The following page has more details. If the head unit isn't damaged, the shield ground could be open in the amplifier.

Temporary Shield Repair

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2 Answers

Rockford Fosgate 800a2 To 2 SVC 2ohm subs

Ok.. Bridge the two sub into 4ohm than bridge to amp.

So. this how it goes.

sub1 + -
to      | |
sub2 - +
=      4ohm

           From Sub
            -          +  
            |           |
amp (L) - + (R)- +

This will use the full potiental of RF 800a2 amp. I believe it like 1153 watts max out.

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1 Answer

Amp makes subs pop

It sounds like your amp chip has gone bad, here is some thing you can try turn on your unit then start tapping on top of with your finger not hard see if the any of the pops matches your finger taps some times when the chip starts to go out it well act like that.

Nov 04, 2006 | Orion 2500D Car Audio Amplifier

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