Problem with the system

So I was driving while playing my sytem(not pounding it too hard) and after about 10 minutes, the bass cut completely out. I checked the amp and it still turns on and the vocals still play, but with the subs on there is no bass. I have 3 Kicker S12L7's and an Autotek MX-3000.1 amp. Anyone have any idea what this could be, blown subs, blown amp, loose wires, etc?

Thanks in advance.....

It's hard to tell w/out troubleshooting and elimination...

did it ever cut back on? sometimes undervoltage protection will kill the output.

and then you got the usual suspects; open, shorts, grounds, and fuses.

and then there's the rca's and the HU itself. I once had a problem with my HU's rca's outputs puttin' out way too much voltage, but it was cool 'cause everything was under warranty.

I had this problem, it was something with the amp. I didn't fix it until it fried my alternator. Nice huh?

Check all your fuses and wires for lose connections or partialy metled wires or somthing like that expetially if it was a hot day. Maybe you over heated it, although it should be protected you never know. Check all the voltages. Its not likely your subs are blown, they would make some noises. Make shure the head unit settings havent changed.

If you can, take the cover off of your amp and make sure its not blown. Also, what do you mean "the vocals still play?" Do you have other speakers hooked up to your amp and they play, but the subs don't, or that when you switch on the lpf it doesn't play, but works fine otherwise?

All the settings did change but that's because I just put in a yellowtop battery. As for the vocals, they have a separate amp than the subs. The amp to the subs also turns on, but produces no bass. I blew an amp previously and when it happened, my subs would make a popping sound every 5 seconds or so. My subs don't do that now so I'm hoping I can rule out the possibility of blowing another amp. Also the voltage seemed fine. I hope its just a loose wire(don't think it's a blown fuse cuz i bought an extra big one) but I'm not totally sure. I'm gonna have a friend look at it Monday hopefully.

P.S. It was evening time and the weather was nice-to a bit chilly.

I had a similar problem with my subs thumping. I had to turn down my amp a little bit to make it stop. I think it might have to do with my rca imput from my Kenwood head unit.

Don't rule out the amp being blown. I blew mine, and it made no sounds ever, the amp turned on and everything but went into protection instantly. Unless you have a short or didn't hook the power wire up correctly when installing the new battery, my bet is that the amp is blown.

But why would my amp blow? I had it wired at 2 ohms (prolly 2.66 or something cuz i have 3 subs) I wasn't maxing the amp I don't believe. What else would cause the amp to blow?

what voice coil model are those subs and how do you have them wired?

are you sure there was no power avail. on your steady hot, because if you short it to ground while the amp is grounded, 9 times out of 10 that's pretty much a wrap for your amp...

I have dual 4 ohm voice coils. I believe its wired around 2 ohms in parallel but don't quote me on that. The amp turns on and goes directly to safe mode.

wait, you have 3 dual 4ohm subs and everything is in parallel? So all 6 + are connected to the + on the amp and all 6 - are connected to the - on the amp?

If so you have it wired at .67 ohm

Then maybe it's wired in series, I'm not sure, but its at a 2.67 ohm load I believe.

series and parallel probably...

yeah series/parallel will give you 2.67, if it's wired like that then the final impedance isn't the problem. That's a pretty complicated wiring setup though, any chance you have a multimeter so you can check that it's right?

No I don't. Whats a multimeter do and do retail stores have any for use? I know my voltage was normal at the time.

They are cheap. I got one at a local auto parts store for less than $20. Also, try hooking up just one sub and see if that works to make sure that impedence isn't the problem

Someone tossed this possibility. The reason the bass is out is beacause i blew one of my subs and the amp goes to protect mode automatically. One of my L7's is actually an L7 but says L5 on the sub. My friend said this occurs when the L7 is refurbished. He said that the sub didn't blow before because I wasn't putting the type of power to it before that I am now. Has anyone ever heard this theory about refurbished subs, and is that an accurate assumption of why the amp goes into protect mode?

the (perfect world) idea behind refurb products is that the manufacture restores a defective sub (or any product) to like new condition and resale it for a lower cost, to basically recoup their expenses without it being a total loss. what I heard from two guys I know that used to refurb computers is that a lot of returns just get repackaged and marked refurbished. and the ones that actually get refurbished...well lets just say, it's not the most quality controlled industry. thats mainly because they know the lure of the cheaper price will let them basically get away with murder. you should really buy refurbs with both eyes open

They are cheap. I got one at a local auto parts store for less than $20. Also, try hooking up just one sub and see if that works to make sure that impedence isn't the problem

less than 1 amp of current can cause death, when your dealing with life threatening currents a $20 multimeter probably would not be the best choice...

I have dual 4 ohm voice coils. I believe its wired around 2 ohms in parallel but don't quote me on that. The amp turns on and goes directly to safe mode.

which protection light come on?

The light on the amp goes on instantly. Can't remember if it says safe mode or protect mode.

less than 1 amp of current can cause death, when your dealing with life threatening currents a $20 multimeter probably would not be the best choice...


less than 1 amp of current through your heart can cause death, but do you realize how much voltage it takes to get an amp of current flowing through the center of your body?

Yes these currents would be life threatening if they were running through your body, but they aren't, and it's not dangerous. If you had a ridiculously long tongue you could put your tongue on the + and - terminals on your batt and you'd be perfectly fine. A $20 multimeter is fine, what would a more expensive one do that could possibly "protect you" that a $20 one couldn't?

some amps have labels under the protection lights letting you know what the problem is...mine have thermal, low ohms, low voltage protection lights. and there are a few out there that also have offset protection lights...which one come on for you?

less than 1 amp of current through your heart can cause death, but do you realize how much voltage it takes to get an amp of current flowing through the center of your body?

Yes these currents would be life threatening if they were running through your body, but they aren't, and it's not dangerous. If you had a ridiculously long tongue you could put your tongue on the + and - terminals on your batt and you'd be perfectly fine. A $20 multimeter is fine, what would a more expensive one do that could possibly "protect you" that a $20 one couldn't?

the both of us agree that 1 amp can kill you..ok..lets leave it alone
now, as far as working with life threatening currents,
that is exactly what you're doing when you're working on your cars electrical system...
any bona fide, qualified, licensed electrician (tech or engineer) learned way back in electricity 101
that the difference between going home and going to the hospital is your equipment.
All I'm saying is, this is not the time to be cheap. money is not the object, your life is...

we're dealing with 12 volt systems here man

what could a $50 dmm possibly do that would save your life that a $20 dmm couldn't? Hell, what could ANY dmm do that could save your life, or even farther, what in god's name could you possibly do with the electrical system in a car to even be anywhere near death?

we order flukes by the case. the ones we get, go for about 200 a pop...anyway, I'm out...peace

I'm curious to see how using a $20 dmm could threaten life at all at, much less more than a $200 one could. Lord, even if I stick my damn finger on the wires it ain't gonna kill me.

i know there are some real electricians out there, and i'm willing to bet they're laughing harder than I am...

Hahahaha I think all you guys just like arguing with each other. Every thread turns into an argument between the same 5 people or so, and then everyone loses site of why the thread was originally posted. Instead, it turns into a forum where everyone gets overly defensive of why their opinion is right, which in-turn ends up frustrating the original thread poster, because their problem remains. Anyways, turns out one of my subs is blown so the amp was going into protect mode so it wouldn't blow the amp itself....

i know there are some real electricians out there, and i'm willing to bet they're laughing harder than I am...


I'm an electrical engineer, and you're right I am laughing pretty hard, because this argument is retarded. Not using a DMM at all won't threaten your life, so how would using a $20 one threaten it? And what extra features on a $200 one would eliminate this deadly threat that a $20 one can't?

You can grab both battery terminals and not feel a damn thing, you could grab any of the wires in your entire car and the most you'll ever feel is a small buzz. We're dealing with 12V systems, not 10,000V systems, nothing you can do short of cutting the battery open and drinking the battery acid will do anything serious to you.

As for the question at hand, it sucks that your sub is blown, but it's good that you found the cause at least.

Well... adam... looks like I am doing the same major as you... this is my first year as an E Engineer Major. So I am having fun doing this stuff. I agree, not much you can do to really screw yourself up with the car electronics, but you can screw your car up.

>> I hope its just a loose wire(don't think it's a blown fuse cuz i bought an extra big one) but I'm not totally sure. I'm gonna have a friend look at it Monday hopefully.<<

YOU DID WHAT???? REPLACED THE FUSE WITH AN EXTRA BIG ONE...more than likely if you replaced the fuse on your amp with one greater than that which your amp originally called for you just fried your amp beyond repair...alowing more ampere's to flow allows more wattage which kills your amps circutry....why oh why do people do this kind of stuff......

I'm an electrical engineer, and you're right I am laughing pretty hard, because this argument is retarded. Not using a DMM at all won't threaten your life, so how would using a $20 one threaten it? And what extra features on a $200 one would eliminate this deadly threat that a $20 one can't?

You can grab both battery terminals and not feel a damn thing, you could grab any of the wires in your entire car and the most you'll ever feel is a small buzz. We're dealing with 12V systems, not 10,000V systems, nothing you can do short of cutting the battery open and drinking the battery acid will do anything serious to you.

As for the question at hand, it sucks that your sub is blown, but it's good that you found the cause at least.

__________________

...you may not be hurt from the actual voltage itself...sine even with your hands wet from hand to hand across your heart is anywhere from 20,000-40,000ohms...and with dry 4-5 times that...but if you are wearing jewlery of any kind and there happens to be a short that is across your metal jewlery...well lets just say you are going to have hella bad 3rd degree burns and probably have to have the ring, watch, or w/e cut from your body because your flech will have burnt to the metal...

am I the only one who know that the amount of mho's your body present to a ckt is dependent upon various factors, (your body's salinity, your body fat %, etc.), and not just if your hands are wet. I mean how much (I) does it take for your natural pacemaker to make your heart beat? And how much (I) does it take to stop it?

YOU DID WHAT???? REPLACED THE FUSE WITH AN EXTRA BIG ONE...more than likely if you replaced the fuse on your amp with one greater than that which your amp originally called for you just fried your amp beyond repair...alowing more ampere's to flow allows more wattage which kills your amps circutry....why oh why do people do this kind of stuff......


The fuse isn't a regulator, it's a safety device. Replacing a fuse with one that's larger won't have any negative side effects unless the amp is already screwed up. And if that's the case, a larger fuse will just allow more damage to happen before it blows, but the amp would have to screw up in the first place before anything would happen.

...you may not be hurt from the actual voltage itself...sine even with your hands wet from hand to hand across your heart is anywhere from 20,000-40,000ohms...and with dry 4-5 times that...but if you are wearing jewlery of any kind and there happens to be a short that is across your metal jewlery...well lets just say you are going to have hella bad 3rd degree burns and probably have to have the ring, watch, or w/e cut from your body because your flech will have burnt to the metal...

that's true

am I the only one who know that the amount of mho's your body present to a ckt is dependent upon various factors, (your body's salinity, your body fat %, etc.), and not just if your hands are wet. I mean how much (I) does it take for your natural pacemaker to make your heart beat? And how much (I) does it take to stop it?

yes it does depend on many things, but the resistance will never drop enough to where you can be harmed by 12V

and a pacemaker isn't attached to your hand now is it?

ahhahaahha

fuses are already rated higher than the (I) of the ckt, if they were not, then the ckt would constantly be underpowered or blowing...

mho's measure how easily electricity conducts through liquid (including body fluid). I spend 16 hours a day working with electricity. Well actually I spend about 8 hours working and 8 hours going through safety checks...

A $200 multimeter is better at measurements with exact tolerances...and, it also happens that it can read voltages just like the cheaper ones. I know we're only talking about car audio applications, and I'm not losing sight of that, but I just beleive better is better. The reason we buy them is because when you got a million dollar inertial navigator guiding you through an underwater mine field and the equipment reads meters and centimeters in volts and milivolts, all of a sudden that +/- tolerance is even more important.

yes I know what mhos are, it's just the reciprocal of ohms, pretty simple concept. Like I said the resistance from hand to hand will never drop enough (or the conductivity will never rise enough) to do any damage when working with 12V systems.

Yes a $200 multimeter is more accurate, but that goes straight back to what I said before. Knowing that the battery voltage is at 12.53 instead of the 12.51 that your $20 multimeter said isn't going to save your life in any way, and thinking that the DC resistance of your sub is 3.254 when it's really 3.257 isn't going to endanger you at all.


edit: I'll try this a different way. Instead of me defending how a cheap multimeter can't endanger you, lets reverse the roles. Please give me one example, just one, where having a .01% error on the measurement instead of .05% will save you from harm? Remember we're talking about car stereo systems here, not the guidance control system for a nuclear warhead.

I'm starting to feel like I'm not going to win this...

gah all this because I told him to get a $20 instead of a $200 one so he could spend the extra $180 towards a new amp. I still think your amp is blown, but I would say take the cover off and see if you can see if its blown.

all this because I'm trying to win my point, regardless of the topic, some people are just competitive...