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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Re: constant thumping

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 Amplifiers

3 Answers

My amp kx1200.1 works only 5 minutes and then getting real hot somebody have any idea

You need to swap your main battery for a high performance kinetic... and maybe even ad a small kinetic in the back as well (fused separately) and see how that works for you. Just one oversized kinetic battery replacing your stock battery may do that trick. Remember, its best to install two batteries of the same brand and size, its ok to use the same brand and two different sizes (a kinetic 2400 and a kinetic 600 for example, but with an isolator) but its easier and simpler to just put in a kinetic 1200 or something that will replace your stock power sucking ineffecient lead acid stuff.

Jul 26, 2010 | Kicker KX1200.1 Car Audio Amplifier

1 Answer

Kicker zx650.4 amp turned off and on

could be a couple of things going wrong. could have overheated and shutdown to protect it. could have hand to many incoming wattage/voltage from your head unit and shutdown. could be that the ohms rating on your speakers is to low or that the speakers could have heated up and bumped the guilds and caused it to shutdown. don't know if you know how ohms works. but here is an exp. if you have and have that is rated at 4 ohm stable and that is the lostes ohm recomened for it. and you have two 4 ohm rated subs. you can run them and run them with no problem as long as you don't bridge them. run them off of the same port on the amp. when bridging them it devides the ohms in half. so 2 4ohms would become 2 ohm. 2 8ohm would become 4 ohm etc. if you are running 4 speakers in pair that are 8 ohm each the total together would be 2ohm. hope this helps. try to duplacate the conditions that was going the other day when it shut down same bass settings same song etc and see if it happens again if so try unhooking one of the speakers and try it again if it don't do it it was overloading it if it was overloading and you know its right ohms etc. send it in sorry this is so long.

May 01, 2010 | Kicker ZX650.4 Multi-Channel Amp - 480W ZX...

1 Answer

Hello. My Kicker kx200.4 is acting funny. The red display light on front/top of the amp is turning on for a second and then turning off, repeatedly. The light on the side (power) is also turning on, red...

the amp is a 200 Watt by 4 im guessing and its doing that because its going into protection mode unhook the subs if it stops then 1 you have a bad sub or 2 the subs are too much for the amp if an amp is rated 200w per chanel its 200 max about 75 rms or 75 normal constant power

Feb 05, 2010 | Kicker KX200.4 Car Audio Amplifier

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 Amplifiers

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

Apr 05, 2008 | Lanzar VIBE266 Car Audio Amplifier

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.

Sep 26, 2007 | Rockford Fosgate Punch 800a2 Car Audio...

3 Answers


I can't find any documentation for your amp; it was made when Jensen was owned by Recoton, and they're no longer in business. With any 4-channel amp, you can't bridge all four channels into a single channel. What you can do, if you're connecting it to a single sub, is to bridge two of the channels into one channel and leave the other two channels unused. It doesn't usually matter which two channels you pick, but some 4-channel amps designate channels 3 and 4 (or rear channels) for the subwoofer. Whichever ones you use should have a "LPF" or "LP" crossover setting available.

Jun 30, 2007 | Jensen A600HLX Car Audio Amplifier

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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