# Sub Amp cuts out at high volume, not an amp problem?



## gfxdave99 (Feb 26, 2011)

boats4life said:


> I have two 12" Kenwoods on a 600w Kenwood amp in the trunk. I'm still using the factory stereo, so the audio input is coming from my right rear door speaker and running to the amp directly via a speaker level input harness. The remote line is running from a PAC terminal. Had this setup in my last car and the amp worked fine, now it cuts out at high volume when the bass hits too hard; However, it did not do this when a similar Sony amp was hooked up the same way. Drawing straws on what to do next, don't want to shell out for another amp when nothing's wrong with the one I have! Anybody have any ideas?


Well how can it not be an amp problem if the Sony doesn't cut out? 

Are you running the same gauge wire to the sub as the previous car? Is the wiring from the amp to the sub the same length? Do you have the subsonic filter turned on? Are you using the amps built in crossover? 

And how many watts is the sony amp and at what ohms are you running


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## boats4life (May 28, 2011)

All the voltage and continuity checks I ran on the amp were fine. All the wiring is the same gauge as the previous car. The filter is always on, I can only adjust the sensitivity and the amp doesn't have a crossover that I know of. The Sony amp was pretty much the exact same amp, just a little newer and not a kenwood, lol. I am currently running @ 2 ohms, I believe, but I haven't actually done any readings since the last time I re-hooked it up.


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## gfxdave99 (Feb 26, 2011)

boats4life said:


> All the voltage and continuity checks I ran on the amp were fine. All the wiring is the same gauge as the previous car. The filter is always on, I can only adjust the sensitivity and the amp doesn't have a crossover that I know of. The Sony amp was pretty much the exact same amp, just a little newer and not a kenwood, lol. I am currently running @ 2 ohms, I believe, but I haven't actually done any readings since the last time I re-hooked it up.


When it cuts out is the amp going into protection mode? 

Does the amp have as good of or better ventilation then it did in the previous car?


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## boats4life (May 28, 2011)

See, I thought about protection mode, too, but I can't imagine that being the issue- there are no jumps or drops in voltage when the cut out occurs. Ventilation is a little better and the amp is no longer sitting under the glass in my old hatchback, so I don't think it's getting too hot...


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## gfxdave99 (Feb 26, 2011)

boats4life said:


> See, I thought about protection mode, too, but I can't imagine that being the issue- there are no jumps or drops in voltage when the cut out occurs. Ventilation is a little better and the amp is no longer sitting under the glass in my old hatchback, so I don't think it's getting too hot...


Well if its protection mode it will shutoff for like 30-90 sec and then come back. Or is it cutting out like just for a split second?


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## boats4life (May 28, 2011)

Split second, just when the bass hits suddenly. If it's a slow, building tone it does ok, but will eventually cut out at a more powerful level. It's really only if the stereo is up past 24 or so... About halfway, which is VERY disappointing... =[


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## boats4life (May 28, 2011)

Although, I've noticed that if I'm not using my iPhone for music and using the tuner or XM instead it will let me crank up to around 30 sometimes a little higher. I really don't use the CD Player at all, so whatevs.


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## osiris10012 (Feb 4, 2011)

sounds like you may have the subs wired at the wrong ohm rating. if you have the subs running at 1 ohm and you only have a 2 ohm stable amp it will definitely do this because it is over drawing from the amp. i have 1 10" re audio wired at 2 ohms with a 1000rms hifonics amp running off a line out converter and can crank mine and have never once had the amp shut off and its already hit over a 100 degrees here.


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## boats4life (May 28, 2011)

Well, it still cut out whether I was bridged or not. How else could I bring the ohms up?


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## osiris10012 (Feb 4, 2011)

what ohm subs are they and are they dual voice coil. depending on how you have the subs wired will change your ohm rating. i can help you out if you let me know. plus what is the amp ohm stability. my guess is the amp is 2 ohm stable and if you have 2 dual voice coil subs that are 4 ohm coils and have them wire in parallel it would be 1 ohm and that would cause the amp to shut off. hopefully this helps you out or sparks an idea for you

this is a cool link at the top you can input what sub set-up you have and it will kick out your wiring options

http://www.the12volt.com/caraudio/woofer_configurations.asp


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## boats4life (May 28, 2011)

Kenwood P-W612 Two 12-Inch Subwoofers and Stereo/Bridgeable Power Amplifier | Car Subwoofers | Modocars.com

That's the setup I have, bought it from a friend, didn't know it was a package deal till I saw this! lol


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## boats4life (May 28, 2011)

NVM, just pulled the subs out and they're w112's, an 8 ohm sub. (I'm typing this as I sweat in the back of my car with tools scattered 'round.) haha I'm just gonna run 'em parallel and see what happens...


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## boats4life (May 28, 2011)

Still cutting out at parallel, everything is hooked up correctly, and the amp doesn't shut off when it cuts out... I can't figure this ish out!!!!


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## Gritts (Jan 23, 2011)

I know this is a dumb thought, but do you have bandpass setting on the amp set for low pass?

Another thought is perhaps adding a power capacitor to stabilize the voltage when the amp is really working hard.


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## gfxdave99 (Feb 26, 2011)

Also check your ground, make sure that you have a fully scraped/clean connection.


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## osiris10012 (Feb 4, 2011)

if there 8 ohms and your running parallel that would definitely not be the cause...i don't know of any car amp that would shut off due to a 4 ohm load...is the amp getting hot at all?...huh i will have to really think about this one..i don't for see a capacitor really helping you in this situation due to the low power draw...it may but i doubt it your not running anything that powerful....i have a 1000rms amp with no cap and have no issues...it may be the fact that your using the speaker inputs on the amp..you ever think of trying a line out converter?...its possibly that the high volume could be making the internal converter throw a fit. not positive though never really messed with using the speaker inputs on the amp...i also agree with gfxdave...there is a factory ground that i am using behind the right trunk cover..there are pics in the thread my new interior lights


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## boats4life (May 28, 2011)

I think I've narrowed it down to a REALLY crappy line out converter.... when I traced back to look at what the 'professional audio shop' installed, it was falling apart and taped together with electrical. I held the connections together by hand with the case off and turned it all the way up no problem. I'm going to replace it and see if that fixes the issue... I can't thank you guys enough for all the ideas!!! I'll post results after I replace it.


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## osiris10012 (Feb 4, 2011)

this is the one i have and love it...it has a dc isolator in it so if you get any alternator whine it eliminates it

Stinger SGN12 55W Fixed Line Out Converter - Sonic Electronix


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## boats4life (May 28, 2011)

Wow, that looks great! You should see the piece of ish one they installed- I should've have posted a pic while I had the wires out.


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## osiris10012 (Feb 4, 2011)

lol...some installers pull that on you its a shame but at least you figure out what the problem is...i highly recommend the one i showed you it works great. i haven't had one issue with it and its already hit 105 degrees here so heat doesn't effect it. there are 3 different versions of it on that site. they have a pretty some of the best deals i can find. i just liked that one the best


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## boats4life (May 28, 2011)

On a side note, check out what I installed today! =]


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## osiris10012 (Feb 4, 2011)

nice i bet it sounds awesome


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## boats4life (May 28, 2011)

It's like heaven on earth. =]


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## osiris10012 (Feb 4, 2011)

if the cruze wasn't my wifes car it would have already had one...lol


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## boats4life (May 28, 2011)

Changed LOC, nice PAC one, but still cutting out with the volume around 30ish. This is REALLY killing me...


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## Gritts (Jan 23, 2011)

boats4life said:


> Changed LOC, nice PAC one, but still cutting out with the volume around 30ish. This is REALLY killing me...


Did you ever try a capacitor?


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## boats4life (May 28, 2011)

I did think about it, but wasn't sure if it would fix it... I guess it's worth a try, lol. I'll probably get one this weekend and try it.


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## osiris10012 (Feb 4, 2011)

i'm sorry, but if you only running a 400w max amp there is no need for a capacitor. you are only running 150 to 200w rms(i am assuming). that amp isn't going to draw enough power to require a cap. thats my opinion. like i have already stated i am running a 1000w rms amp with no cap and have absolutely no issues. what are you listening to when it cuts in and out...cd, radio, aux, xm?


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## boats4life (May 28, 2011)

It happens on all inputs but has more tolerance when it's not the aux- my iPhone. I checked the amp ground last night and it looked like they didn't even sand it down before they put it in, so I'll try to fix that first and see if it helps.


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## osiris10012 (Feb 4, 2011)

there is a factory ground behind the right trunk cover pretty much to the right of the right trunk hinge on the back of the wheel well. if you pull that cover you will see it...thats where i have my ground...works great and no sanding its already perfect. its actually where the factory radio amplifier has its ground


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## boats4life (May 28, 2011)

Well, I'm sitting in the car now, and I've gotten a good ground. At first I had it all the way up, with not a single cut out. Went an entire song. Then, next song starts cutting out at about thirty again... =[


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## boats4life (May 28, 2011)

New info, the cutout point varies with song and point in song. Almost like it's surging. However, I'm not seeing any blinking for overload protection or anything like that on the amp...


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## boats4life (May 28, 2011)

Right now I'm thinking that there's too much input signal current, but I'm not sure how to retard it to be able to test this theory.


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## osiris10012 (Feb 4, 2011)

the only way you could really adjust that is if you got an adjustable line out converter. another question i have is which speakers are tapped into front or rear. i have mine tapped into the rear. i don't know of a way to test the output. i think you need a special meter. not positive though


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## toydriver00 (May 4, 2011)

I had this same problem when I didn't realize that I had a 2ohm sub on a 4ohm amp circuit. You may want to make sure you are wired correctly. It sounds like you are overdriving your sub circuit... is the amp 4ohm or 2 ohm stable, from reading your previous posts, you have 2- 8 ohm subs. So they need to run in parallel on a 4ohm circuit. The picture below shows the subs in parallel. You will need a 4 ohm stable amp, or a 2ohm stable that is bridged...


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## osiris10012 (Feb 4, 2011)

he said that he's got 2 8 ohm subs so there is no way he is over driving the amp. the lowest he could run them is 4 ohms. i have never heard of an amp over surging at a 4 ohm load


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## boats4life (May 28, 2011)

The wiring is right, the power and ground are right, everything is right. It really just seems like too much current from the factory speakers through the LOC. It is adjustable, but even all the way turned down I still get the cutout. Even with the speaker level input _without_ an LOC it still cuts out just the same... I'm seriously at wits end.


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## boats4life (May 28, 2011)

For a little more background on the amp itself and the subs running on it, here are some links...

Kenwood KAC-6202 (kac6202) 2-Channel Amplifier - Sonic Electronix

Kenwood Electronics Europe | Component Speakers > KFC-W112S


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## osiris10012 (Feb 4, 2011)

is your loc tapped into the front or rear speakers?


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## boats4life (May 28, 2011)

The right rear door speaker.


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## toydriver00 (May 4, 2011)

osiris10012 said:


> he said that he's got 2 8 ohm subs so there is no way he is over driving the amp. the lowest he could run them is 4 ohms. i have never heard of an amp over surging at a 4 ohm load


 
I have because I did. Way back in the day before I started repairing electronics and installing friends systems, I learned the current and resistance lesson the hard way. I had two 4ohm subs in // run to a bridged 4 ohm amp. So, I had a 2ohm circuit. Less resistance and extra current caused it to cut out.


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## toydriver00 (May 4, 2011)

boats4life said:


> The right rear door speaker.


 
I am wondering if your problem isn't in the stereo, or the LOC. Which wire are you using for ground on the LOC. The PAC loc requires that the blue and black stripe wire be used for ground. The black wire on the PAC LOC is used to bring the RCAs to common, and that reduces noise. Maybe your LOC is wired with the black wire to ground instead of the blue with black stripe?


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## Vulgar_Display (Apr 23, 2011)

Your amp is probably clipping turn down your gains.


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## boats4life (May 28, 2011)

toydriver00 said:


> Maybe your LOC is wired with the black wire to ground instead of the blue with black stripe?


By George, I think he's got it! lol I'm going to have to run it this way and see if anything changes! hahaha


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## boats4life (May 28, 2011)

Ok, I'm sitting in the car with the molding off of the B-pillar. The LOC (the SNI-50A) has White/White&Black Stripe, Black, and GREY/GREY&BLACK STRIPE...
Would you mean having the Black running with the Grey&Black?


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## boats4life (May 28, 2011)

Yeah, that didn't work....


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## toydriver00 (May 4, 2011)

I used a PAC SOEM-4. I though that was what you had for some reason. Sorry to confuse you.


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## toydriver00 (May 4, 2011)

Does your amp happen to have a low line converter built in?


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## boats4life (May 28, 2011)

No it doesn't. It has the adjustable high/low pass filters, input sensitivity, RCAs, and speaker level input on the left side and the power, ground, remote and speaker outputs on the right side.


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## boats4life (May 28, 2011)

You'll probably get more info on the amp from the links I posted earlier than from me, lol-

http://www.cruzetalk.com/forum/30749-post39.html


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## Gritts (Jan 23, 2011)

I don't know how the amp you're using is designed, but it sounds like a problem with biasing. You need to eliminate any DC component you are feeding to the amplifier. Have you tried using a Ground Loop Isolator? This eliminates any DC from the signal source and may prevent the amp from being driven into saturation and cutting out.

FYI the Ground Loop Isolator has RCA type connections and connects in line between the LOC and amplifier.


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## boats4life (May 28, 2011)

I cant believe I hadn't thought of that already... I'm embarrassed. Lol. I work in electronics. I work on f-18s in the navy, and not once did something that simple even cross my mind.


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## toydriver00 (May 4, 2011)

I would try this. I am using the 4 channel version with the radio plug that plugs in the back of the head unit. I can also wire it like you have. This has an isolator like I was speaking about before. The yellow goes to power, blue/black stripe goes to ground, and so does black to become a ground isolator. I didn't need to use black on mine though...

Amazon.com: PAC SOEM-T 2-Channel Premium Line-Out Converter with Remote Turn-On Trigger: Automotive


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## osiris10012 (Feb 4, 2011)

the stinger loc i posted earlier that i have installed in my car has a dc isolator built into it so this may be the reason i haven't experienced any of your issues...


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## Gritts (Jan 23, 2011)

I wonder if the amp works now...


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## boats4life (May 28, 2011)

I'm waiting to get the GLI... It works enough for now, but I will post again when I install it.


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## Kaimumma (Apr 14, 2011)

I'm reading that your current amplifier uses 1x25A fuse. What size fuse are you using at the battery? 

Remember to take the current amount of watts you think is going to the amp and divide by 12 volts. That should be the size fuse you use, which should be close to or near 25A. 

Also, from the sounds of it, you really just don't seem to have enough power running to those subs. I don't remember looking at a link for your subs, but usually if you want a subwoofer to be at it's best, you need to double the amount of power going to it. Example - You're using 2 12" subs...I'll guess around 200 watts RMS a piece? So you'll need an amp to supply nearly 800 watts of power so that they are properly driven.

Now this method isn't something needed, it's more of a suggestion. It's one of the more common reasons why subwoofers cut out. Not enough power............

Logically speaking it just seems that at higher volumes you're sub would cut off because your amp is under to much load. 

My last suggestion is to double check continuity on each side of your fuse by your battery. Sometimes those things go bad and you may not even know it. The fuse may look serviceable still, but the holder itself may not be.


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## boats4life (May 28, 2011)

Kaimumma said:


> I'm reading that your current amplifier uses 1x25A fuse. What size fuse are you using at the battery?
> 
> Remember to take the current amount of watts you think is going to the amp and divide by 12 volts. That should be the size fuse you use, which should be close to or near 25A.
> 
> ...



I'm not sure of the fuse I'm using right now, and I don't have a multimeter to check continuity... As far as the power goes, I would say you're right, but this exact setup work in my Celica when I was stationed in Hawaii. (Mahalo for your help, by the way):th_alc:


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## boats4life (May 28, 2011)

Just installed the GLI, tested and the amp SHUT OFF. I thought it went into protection mode, so I waited for 30 seconds. Then 60. Then 90. I went back and disconnected the RCAs and reconnected and it came back on. The volume limit is still the same, about 25 for input, about 30 for everything else. I used the grounds on the GLI, now it doesn't turn off, but still cuts out. The only things I haven't checked are the RCAs themselves and in the Celica I had an Optima Yellow Top, now I'm just running the stock battery... I'm at a loss.


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## osiris10012 (Feb 4, 2011)

i am not sure but from the sound of it...that amp may be the issue..if you have the subs wired correctly and you went threw everything else and its good. including the fact that you have a gli and a good loc. this is definetly an odd behavior for a system. out of curiousity do you have a buddy or somebody you know that may let you try there amp to see if it cuts out to narrow everything down? or maybe even there subs and amp?


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## boats4life (May 28, 2011)

I'll have to look around, I just moved here and don't know many people, let alone anybody else with a system... I have never had this many issues with a system, and this setup worked perfectly days before I put it in the Cruze. The amp used to overheat in my Celica before, but it was right under the glass of the hatchback and I was stationed in Hawaii, so it was always hot.


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## STUDLEE (Jul 6, 2011)

Visually inspect your fuse. My coworker just had this exact problem with his 4chan. Fuse and holder was melted. Continuity will still read good until the amp goes to draw that high level of current. Also check EVERY connection. Most inline fuses for large gauge wiring makes a connection on both sides of the fuse. I'm guessing if you alread ruled out a bad ground and everything else, It may be the fuse. 

If not, it sounds like you're either OVERDRIVING the input to the amp (turn down your high to low converter gain), or you're factory deck output isn't sufficient enough to drive the high to low converter. If the fuse isnt the issue, try adjusting your balance and fader for more and less power to the right rear speaker when your amp starts to cut out. This should give you an answer.

Edit: Have you tried using the high level input on the amp? I assume if you bought it used, the first owner no longer has the high level input harness that goes with the amp. if you have access to it, you can also use this as a troubleshooting tool. Also, don't most high level inputs require a 2ch input (left and right)? If so, you may not have sufficient power with tapping into just 1 side (you may have done both sides, I just haven't had time to read every post in the thread)


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## boats4life (May 28, 2011)

If I turn down the outputs on the converter it still cuts out, AND I can't hear much. It is quite possible the factory deck isn't putting out enough... but I'm not sure how if at all to remedy that. Fuses are all good, ALL connections are good, and all components are good.


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## STUDLEE (Jul 6, 2011)

Have you tried using the high level input on the amp? I assume if you bought it used, the first owner no longer has the high level input harness that goes with the amp. if you have access to it, you can also use this as a troubleshooting tool. Also, don't most high level inputs require a 2ch input (left and right)? If so, you may not have sufficient power with tapping into just 1 side (you may have done both sides, I just haven't had time to read every post in the thread)


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## boats4life (May 28, 2011)

I did order the speaker level input from Kenwood and install it, I haven't tried it lately as I've been trying to get the RCAs to work, but I'll try again. I didn't tap both sides, but even if I only run one channel it still cuts out... I could try tapping the left as well.


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## osiris10012 (Feb 4, 2011)

if your amp constantly overheated it may have slightly damaged it. causing it to act the way it does.


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## boats4life (May 28, 2011)

I don't know... I never had any problems with it before. It had no problem handling full volume on an aftermarket deck.


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## Gritts (Jan 23, 2011)

Does your amp have two RCA type inputs left and right? 

You may have to connect the speaker from the other rear door to the second amp input...

Here's the way I did mine: 

1. Connections from the two door speakers to Line Out Converter, Left and Right
2. Then connect the LOC's RCA connections to an GL Isolator, Left and Right
3. Then from the GL Isolator to the two RCA connections on the Amp. L&R
4. Then connections from Amp's two output channels to each of the two speakers.

I used 6x9s on this setup--not subwoofers. If this doesn't work time for a new amp.


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## boats4life (May 28, 2011)

I've resorted to getting rid of this setup and moving down to 10's anyway. Hopefully they'll actually work, lol.


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## boats4life (May 28, 2011)

This thread has moved to here: http://www.cruzetalk.com/forum/36-electronics/2958-arcing-electrical-fire-type-smell.html


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## jakkaroo (Feb 12, 2011)

sorry for the thread digging i bought a jl audio w3 and a 1400 mono amp and took it to a well know audio shop,i paid them 160 bucks and i go to pick it up they say the amp is broke they want me to buy a kenwood,i tell them the amp worked fine 2 nights ago so i left with no system working take it to my friend we plug it back into his car,works fine i call the guy mad he says bring the truck in for him to see,is there a factory amp and stuff the guy needs to know about will wiring to a stock head unit


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## boats4life (May 28, 2011)

jakkaroo said:


> sorry for the thread digging i bought a jl audio w3 and a 1400 mono amp and took it to a well know audio shop,i paid them 160 bucks and i go to pick it up they say the amp is broke they want me to buy a kenwood,i tell them the amp worked fine 2 nights ago so i left with no system working take it to my friend we plug it back into his car,works fine i call the guy mad he says bring the truck in for him to see,is there a factory amp and stuff the guy needs to know about will wiring to a stock head unit


I understood about half of this.

If you are asking how to wire in subs from a stock head unit in the Cruze, a PAC Audio GM-AA44 is the best way to go. Its all plug and play.


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## jakkaroo (Feb 12, 2011)

boats4life said:


> I understood about half of this.
> 
> If you are asking how to wire in subs from a stock head unit in the Cruze, a PAC Audio GM-AA44 is the best way to go. Its all plug and play.


no,im sure the guys wired it right,the amp goes into a protect mode,did they wire it wrong


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## Ski (Sep 2, 2011)

hi i work at a car audio place it is united states oldest kenwood dealer and we installed a similar amp i believe the same one in a cruze and it had the same problem... some how what it was doing was sending too much current to the amp, even when we put smaller fuses in line it was just keep cutting out. something with the designing in the kenwood amps it would just freek out when the volume was turned up and it would get too much current. 

so the answer to the problem is not to install kenwood amps into the cruze's and we are going to stick by that even being that kenwood is a big thing. 

i hope this helped.


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