Blew out a JL 12w7 first day of purchase with a JL 1000/1 amp...how did this happen?

[teamquakecelica 10+ year member]

WOW.. most of the posts on here act as though the OP spent THEIR money... if he thought it was worth it... then it IS.. its called perception..

Topic- ABSOLUTELY NOTHING to do with break-in period, sounds like a combination of shop and user error...

P.S. I don't believe the "i wasn't playing it loud" crap.. not one NOOB in the history of car audio that has blown a sub has ever admitted to playing it too loud.. ever..

 

[audioholic 5,000+ posts]

Why you need a remote gain? Anyway, sounds like the combo of that and bad settings.

Lots of people here use remote gain knobs. They just incorrectly call them their 'bass boost' knob. Most modern 'bass boost' knobs are just a gain adjuster. And before you ask, no it wont let you push your amp to clipping, unless you've set your gains on the amp too high. Max setting on the gain adjuster knob is whatever your gain setting on the amp is. The most accurate name for the knob would be a 'gain attenuator'.

 

[audioholic 5,000+ posts]

and jl probably wont fix it for free the shop will most likely eat the cost but it wont be free

That makes no sense. The bottom line is, the OP wont have to pay. Furthermore, I dont understand why you seem to be morally insulted because JL Audio wont pay for the shop's mistake. Why should they? If the shop installed it wrong, causing the failure, the shop should 'eat' the cost.

As I said in the other thread, the guy comparing a W7 to a Warden doesn't seem to understand the somewhat subtle differences between a SQ/SQL sub, and an SPL sub.

You guys get carried away with this anti-JL crap sometimes. You rag on JL owners because you think they feel superior because of a name brand, and then you justify how much more superior your name brand choice was than theirs. Its pretty ironic.

 

[the Answer 10+ year member]

That makes no sense. The bottom line is, the OP wont have to pay. Furthermore, I dont understand why you seem to be morally insulted because JL Audio wont pay for the shop's mistake. Why should they? If the shop installed it wrong, causing the failure, the shop should 'eat' the cost.
As I said in the other thread, the guy comparing a W7 to a Warden doesn't seem to understand the somewhat subtle differences between a SQ/SQL sub, and an SPL sub.

You guys get carried away with this anti-JL crap sometimes. You rag on JL owners because you think they feel superior because of a name brand, and then you justify how much more superior your name brand choice was than theirs. Its pretty ironic.

i compared the price he payed for his sub to the price of the warden, in no way was i comparing the subs other than price. and i do understand that they are TOTALY different subs.

 

[john.mulvehill 10+ year member]

To answer your question, the sub didn't blow because it wasn't broken in properly, so don't worry about that....

the shop is blaming me 100% for the blown and saying that they did the install just fine. I find it strange though that there was a funny smell in the car as I was driving home from the audio shop. I smelled that smell the whole way home and called the audio shop about it. They said it was probably just the air being pushed out of the box. The subs cut out shortly after and there was smoke in the trunk.

you guys are positive that i am not to blame? i couldn't have blown the sub that quick by playing the volume too loud? is the problem most likely related to the shop incorrectly setting the gain? btw, the installer said he put the gain up to one third. but interestingly, when they were putting the big box into the trunk, the same installer said "i hope the gain is set right because I am not going to be able to get to it once that box is lodged in the trunk." This does not sound like a very confident statement about the gain being set correctly.

 

[john.mulvehill 10+ year member]

Most modern 'bass boost' knobs are just a gain adjuster. And before you ask, no it wont let you push your amp to clipping, unless you've set your gains on the amp too high. Max setting on the gain adjuster knob is whatever your gain setting on the amp is.

Here is the bass control device I purchased

Would you still call that a gain attenuator? If so, if the installer set the gain on the amp too high, and I had the bass control knob (gain attenuator) at the max setting (which i did), then this could have sent clipping which could have blown the sub? So, referencing the post I just made about him setting the gain at 1/3 and then saying that he hopes that was right because he cant get past the box, it seems likely that he set the gain too high and then when i had the gain attenuator knob on max that that sent clipping to the amp to blow the sub..

 

[john.mulvehill 10+ year member]

If the shop installed it wrong, causing the failure, the shop should 'eat' the cost.

The problem is that the shop is admitting zero blame and is saying that this is all my fault for playing it too loud before the sub was broken in. They want to tune down the replacement sub once it comes in so that I can't play it as loud and they don't have to worry about it blowing. I also am not sure yet if they are going to try and make me pay shipping to JL because JL only pays return shipping back to the shop.

 

[audioholic 5,000+ posts]

Here is the bass control device I purchased
Would you still call that a gain attenuator? If so, if the installer set the gain on the amp too high, and I had the bass control knob (gain attenuator) at the max setting (which i did), then this could have sent clipping which could have blown the sub? So, referencing the post I just made about him setting the gain at 1/3 and then saying that he hopes that was right because he cant get past the box, it seems likely that he set the gain too high and then when i had the gain attenuator knob on max that that sent clipping to the amp to blow the sub..

I just looked up the description of that bass controller, it is actually a bass boost (from 0 to +6db). That setting, with a high volume level on the h/u, could send the amp into clipping. Unless the installer set the gain, by ear DMM or o-scope, with the bass boost at max. Which he probably didn't.

 

[Stalin-ohaulic]

The problem is that the shop is admitting zero blame and is saying that this is all my fault for playing it too loud before the sub was broken in. They want to tune down the replacement sub once it comes in so that I can't play it as loud and they don't have to worry about it blowing. I also am not sure yet if they are going to try and make me pay shipping to JL because JL only pays return shipping back to the shop.

There you go! Now you admit it. Still in this case, as an uneducated consumer, you expected things to be set up so you could turn your little knob as far as you want and nothing gets damaged. That is not an unreasonable expectation since you paid to have that done. Once you get your new sub and they put it in, you will be disappointed with the output I'm sure. Don't let that bother you. Unhook your little bass boost knob and stick it in a closet. It's how you blew your sub. ...... if you clip those jl / series amplifiers too long they will fry. I mean 20-30 minutes of clipping will do that thing in. You're lucky it just blew the sub honestly.

 

[power-fanatic07 5,000+ posts]

Those prices are fuking horrible!

No joke brah, You can get a complete system with active 3 way front stage, 2kw amp, 15" sub that will kill that dub seven.

 

[hispls 5,000+ posts]

OP, I'd ignor most of the responses in this thread, which you probably are anyway....
To answer your question, the sub didn't blow because it wasn't broken in properly, so don't worry about that.... as far as why the sub blew, it shouldn't have... but without looking at the sub and install no one here can say what happened... there is a good chance it was a defective sub... either shorting lead wires or a bad coil...

Let the shop take care of you, that is why people go to a brick and mortor shop... They sell it, install it, and if something goes wrong they are supposed to make it right... The buy online sack riders posting in this thread seem to miss the point that not everyone wants to DIY and may also want some face to face customer service...

Once the shop gets you a new sub, have them put it in and play the system before giving it back to you... If there is any doubt things are not setup properly you might want to take it by another shop to take a look, or call and talk to JLs tech support... If by chance everything is setup where it should be, and you cook another sub, there may be a possibility something is wrong with the amplifier...

Hope you get it sorted out..

^^^^

What he said.

I definitely agree if you're a novice and going to (and paying) an "expert" to install it you expect them to set things up so they don't blow up or at least warn you what you should avoid doing to not blow things up.

For the record, this is what a 900$ SQ sub is supposed to look like:

 

[john.mulvehill 10+ year member]

I just looked up the description of that bass controller, it is actually a bass boost (from 0 to +6db). That setting, with a high volume level on the h/u, could send the amp into clipping. Unless the installer set the gain, by ear DMM or o-scope, with the bass boost at max. Which he probably didn't.

When you hook up that bass controller to the slash amp specifically, it actually goes from 0 to +15db. I spoke to a knowledgeable JL tech support representative and he told me that there should be no problem having that specific bass knob all the way up and having the volume loud on the head unit. However, the caveat here was that he said the gain should be set based on the head unit being 3/4 of the way up. Then, the head unit volume should stay below 3/4 of the max and the remote bass control could be cranked up all the way without having to worry about blowing the system.

So when I get the replacement sub, I should make sure the installer sets the gain by ear DMM or o-scope with the head unit volume at 3/4 of the max? Where does the 54.7 number come in that the JL tech support rep said the gain should be tuned to?

 

[john.mulvehill 10+ year member]

There you go! Now you admit it. Still in this case, as an uneducated consumer, you expected things to be set up so you could turn your little knob as far as you want and nothing gets damaged. That is not an unreasonable expectation since you paid to have that done. Once you get your new sub and they put it in, you will be disappointed with the output I'm sure. Don't let that bother you. Unhook your little bass boost knob and stick it in a closet. It's how you blew your sub. ...... if you clip those jl / series amplifiers too long they will fry. I mean 20-30 minutes of clipping will do that thing in. You're lucky it just blew the sub honestly.

Read my above post about how the JL audio tech support rep told me that there is no problem using the remote bass knob with the slash amp and that it's actually made to work with the slash amp. He said there should be zero issue with cranking the bass control knob to the max as long as the gain is set correctly. So rather than the knob being the problem, it looks like the gain setting (and gain setting in relation to the bass knob max setting) is the problem.

 

[Stalin-ohaulic]

Read my above post about how the JL audio tech support rep told me that there is no problem using the remote bass knob with the slash amp and that it's actually made to work with the slash amp. He said there should be zero issue with cranking the bass control knob to the max as long as the gain is set correctly. So rather than the knob being the problem, it looks like the gain setting (and gain setting in relation to the bass knob max setting) is the problem.

You have to understand what is happening in order to know whether it's ok to "crank" the bass knob. To get +3db, the amp tries to double the power at the frequency that the bass boost is centered at. To get +6 db, it has to double it again. (this is all done on the input side, so cranking the BB just causes you to clip like mad... since the amp is not going to put out more than 1000 watts)You COULD crank this open and set the gain playing a tone at its center frequencies, but then all frequencies above and below would be rather weak and this one would be strong. Even if the shop set the gain to put out 1000 watts at your subs nominal impedence, once you crank the bass boost it is going to cause your amp to clip like mad. I've seen enough blown slash series amps to know this for a fact. Your little JL tech support guy might work for JL, but I'd guess he's not bass boost happy.

You can argue until you're blue in the face, but i'm not going to make this up. You're the one who is going to be suffering with no bass if you repeat your mistake again.

 

[armyatc1]

hey threadstarter... I have an alpine type s in a very high output superbox and I will sell it to you for 750$. PM me...

sounds like someone drank their local shop's JL audio kool aid.