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Magic34
08-27-2004, 05:47 PM
I blew a 12" JBL GTI subwoofer. I have 4 in my boat and I also think one of my 2200 watt JBL amps went bad. What's with a company putting "4000 Watts" in large bold print on the woofer cone, when 1100 watts RMS blows the hell out of it? Kind of mad since I haven't used it a lot and I pulled it out of the garage today and palyed the system, only to have the subs cut out at high volume because of the blown subs. :mad: :mad: :burningm:

PHX ATC
08-27-2004, 07:59 PM
Damn, now the boat will be 10 mph slower than yesterday. :2purples:
Blown amp too? Maybe you need to downgrade to the PHXATC special. :shift:
You gonna get the amp replaced too?

Magic34
08-30-2004, 08:44 AM
What I don't understand is that last time out, I was pounding the crap out of the system at the lake, put the boat back int he garage and all was well. When I turned the system on last week, no go at more than 35% volume for the subs. The highs work fine.
I am running all JBL power with 2-2200's for the subs and 2-1100's for the highs. One woofer was blown and I'm guessing there may be more, but an amp may also be bad. Does this sound right?

B-Ron
08-30-2004, 10:19 AM
What I don't understand is that last time out, I was pounding the crap out of the system at the lake, put the boat back int he garage and all was well. When I turned the system on last week, no go at more than 35% volume for the subs. The highs work fine.
I am running all JBL power with 2-2200's for the subs and 2-1100's for the highs. One woofer was blown and I'm guessing there may be more, but an amp may also be bad. Does this sound right?
There are several possibilities:
1. your enclosure is constructed in a way that prevents proper airflow into the sub's motor assembly.
2. A bad amp like you said.
3. Voice coils wired incorrectly (will blow sub and/or amp)
4. Enclosure specifications beyond the scope of the sub's specifications. A poorly tuned ported enclosure will dramatically decrease the sub's power handling capabilities at frequencies beyond the sub and enclosure's combined frequency curve.
Hope this sheds some light on your dilemma. If you give me a little more info about your system I can give you a more accurate diagnosis.

Havasu Hangin'
08-30-2004, 11:04 AM
I'll add that if you blew one...depending on how they are wired...it can affect more than one.
Heat kills them.

ROZ
08-30-2004, 11:23 AM
4. Enclosure specifications beyond the scope of the sub's specifications. A poorly tuned ported enclosure will dramatically decrease the sub's power handling capabilities at frequencies beyond the sub and enclosure's combined frequency curve.
Also would like to add that eliminating the frequencies on the low end of the curve with a subsonic filter will help lenghten the life of your subwoofer.

Magic34
08-30-2004, 11:37 AM
B-Ron,
I am wondering if the battery that supplies the deck with power is low. If that is the case, would this happen. I am using a rockford deck and changer. All amps are on a different set of batteries from the deck and remainder of the boat(amps have their own batteries).
The enclosure is the same that they have built for multiple systems, and this is the only one having problems, so I hope it's not the box.
If it was wired wrong, would it rock for 2-3 months and then go bad?
Here is what I have. 2 JBL 1100's running 12 NKD116 MB Quart. 2 JBL 2200's running 4 12"GTI subs. Rockford deck.

ROZ
08-30-2004, 12:51 PM
RMS on those subs is 700 watts.... :cry:

Magic34
08-30-2004, 01:47 PM
RMS on those subs is 700 watts.... :cry:
:mad: :mad:
Nice, and they put on bold print on the cone "4000 Watts"
So, I'll blow 12 spekaers during the warranty period and then tell JBL to shove it.

B-Ron
08-30-2004, 02:04 PM
I think you should just try some better amps. check this out...
BPX2200.1
Power Output: 650 watts RMS x 2 channel at 4 ohms
and ≤ 1% THD + N
2450 watts RMS x 1 channel at 4 ohms,
14.4V supply and ≤ 1% THD + N
1810 watts RMS x 1 channel at 1 ohm,
14.4V supply and ≤ 1% THD + N
Signal-to-Noise Ratio: 67 dBA (reference 1 watt into 4 ohms)
Dynamic Power: 2940 watts at 4 ohms
Effective Damping Factor: 6.28 at 4 ohms
Frequency Response: 22Hz – 302Hz (-3dB)
Maximum Input Signal: 7 V
Maximum Sensitivity: 250 mV
Output Regulation: .12 dB at 4 ohms
These amps seem to be full of distortion. Especially if your subs are wired parallel, giving you roughly a 1.5 ohm load mono per amp (dual 6 ohm voice coils, right?). If the signal to noise ratio is 67 dBA at 4 ohms (not to mention only tested at 1 watt) then at 1.5 ohms cranking for hours in the heat, your subs could have easily been blown due to a very dirty signal. They may be able to handle 4000 watts, but there are a lot of factors involved... clean musical watts vs. thermal and distorted watts. So basically, these subs were pounded on for months with a 'junk food diet'.
Also check out that damping factor spec. these amps don't control the sub very well at all.

Magic34
08-30-2004, 03:08 PM
I think you should just try some better amps. check this out...
BPX2200.1
Power Output: 650 watts RMS x 2 channel at 4 ohms
and ≤ 1% THD + N
2450 watts RMS x 1 channel at 4 ohms,
14.4V supply and ≤ 1% THD + N
1810 watts RMS x 1 channel at 1 ohm,
14.4V supply and ≤ 1% THD + N
Signal-to-Noise Ratio: 67 dBA (reference 1 watt into 4 ohms)
Dynamic Power: 2940 watts at 4 ohms
Effective Damping Factor: 6.28 at 4 ohms
Frequency Response: 22Hz – 302Hz (-3dB)
Maximum Input Signal: 7 V
Maximum Sensitivity: 250 mV
Output Regulation: .12 dB at 4 ohms
These amps seem to be full of distortion. Especially if your subs are wired parallel, giving you roughly a 1.5 ohm load mono per amp (dual 6 ohm voice coils, right?). If the signal to noise ratio is 67 dBA at 4 ohms (not to mention only tested at 1 watt) then at 1.5 ohms cranking for hours in the heat, your subs could have easily been blown due to a very dirty signal. They may be able to handle 4000 watts, but there are a lot of factors involved... clean musical watts vs. thermal and distorted watts. So basically, these subs were pounded on for months with a 'junk food diet'.
Also check out that damping factor spec. these amps don't control the sub very well at all.
EFF ME!!!!! :burningm: :burningm: :mad: Damnit

ROZ
08-30-2004, 03:22 PM
Those specs are at 14.4 and not at the 12v you run at with the alternator(s) not running. Distortion should be a little less...

Magic34
08-30-2004, 03:24 PM
Those specs are at 14.4 and not at the 12v you run at with the alternator(s) not running. Distortion should be a little less...
The amps are hooked up to 6 Trojan 6V batteries wired to 12V. Good, bad, ugly??? :hammerhea

ROZ
08-30-2004, 03:28 PM
Rated Power:
1000 W RMS @ 1.5 ohm-4 ohm
(11V-14.5V)
THD at Rated Power:
<0.05% @ 4 ohm
S/N Ratio*:
>95dB below rated power
Frequency Response:
5 Hz-500 Hz (+0, -1dB)
Damping Factor:
>500 @ 4 ohm/50 Hz
Input Range:
switchable from 200mV-2V RMS
to 800mV-8V RMS
JL specs..
I wonder what frequency the JBL's dampening wat tested at..

B-Ron
08-30-2004, 03:43 PM
Really what it boils down to is that you're feeling like you've wasted a ton of money on amps and/or subs. Ultimately you need to get your boat to an experienced tech to get to the bottom of this before you spend anymore money and before you deem your equipment junk. You could have gotten a bad amp, a bad sub, your power wire could even be too small and starving your amps of current which would cause thermal failure. We can go on and on about all the possibilities without physically digging into the problem when it could really be just about anything causing this mishap. My professional advice... take it to someone before you spend another dime.

Magic34
08-30-2004, 03:47 PM
Really what it boils down to is that you're feeling like you've wasted a ton of money on amps and/or subs. Ultimately you need to get your boat to an experienced tech to get to the bottom of this before you spend anymore money and before you deem your equipment junk. You could have gotten a bad amp, a bad sub, your power wire could even be too small and starving your amps of current which would cause thermal failure. We can go on and on about all the possibilities without physically digging into the problem when it could really be just about anything causing this mishap. My professional advice... take it to someone before you spend another dime.
They are working on it Wednesday. I had to change an impeller on Saturday :mad: , and now the stereo is getting all of the heat from me.
Sh*tty weekend with regards to the boat.

Magic34
08-30-2004, 03:48 PM
Rated Power:
1000 W RMS @ 1.5 ohm-4 ohm
(11V-14.5V)
THD at Rated Power:
<0.05% @ 4 ohm
S/N Ratio*:
>95dB below rated power
Frequency Response:
5 Hz-500 Hz (+0, -1dB)
Damping Factor:
>500 @ 4 ohm/50 Hz
Input Range:
switchable from 200mV-2V RMS
to 800mV-8V RMS
JL specs..
I wonder what frequency the JBL's dampening wat tested at..
How much space do they need for a ported box?

B-Ron
08-30-2004, 04:12 PM
How much space do they need for a ported box?
Those specs were for a JL amp. If you're asking in reference to your JBL subs, I'm not sure since we don't use them. I wouldn't recommend using a ported enclosure in an open environment (a boat) for subs soaking up that much power. You're going to have to spend more money how ever you look at it going with a ported enclosure... either more money on mid-bass drivers to compensate for a narrower frequency response, more money on better amps (not saying your's are junk, just not what I would recommend for a sub that handles 4000 watts in a ported enclosure) or more money on continuously replacing subs. Not to mention that ported enclosures require an average of 1.5 - 2 times the amount of air space versus a sealed enclosure for the same sub. Which leads me to the million dollar question... Just what exactly are you looking for?

Magic34
08-30-2004, 04:41 PM
Those specs were for a JL amp.
I realized that after I posted the last comment.
Which leads me to the million dollar question... Just what exactly are you looking for?
I want it to be super, freakin, out of control, stupid loud :D Something like that. Space is not my issue.

Magic34
08-30-2004, 04:43 PM
If I just would have put speaker covers from Billet Boyz USA on the speakers, none of this would have happened. Also, because of the covers from Billet Boyz USA, my boat would have been faster as well.
Good thing I'm adding them this week. :D

B-Ron
08-30-2004, 06:05 PM
I want it to be super, freakin, out of control, stupid loud :D Something like that. Space is not my issue.
Then go with 2 15's in sealed enclosures. I say use 2 Kicker L5 15's but that's a biased opinion since that's what we sell. Power them with a good 1000 watts each (btw, underpowering a sub will kill it). 2 of any of these amps will do:
Kicker 1200.1
PPI DCX 1500.1
JL Audio 1000/1
Rockford Fosgate Power T20001bd
etc...
I recommend 2 Kicker 1200.1 for 2 15" L5, biased, again...but I know it works and sounds great. Put them in a sealed enclosure. You'll also want to look into a single 10" or 2 8" to play the low-mid-bass range. If you want I can draw up a layout of what I would do. Feel free to email me if that's something you'd be interested in.

ROZ
08-30-2004, 06:15 PM
I understand what you're trying to say about under powering a subwoofer, but you may want to rephrase with greater headroom. The way you've written it sounds like playing at low volume will kill a sub... Not the case :rollside:

B-Ron
08-30-2004, 06:40 PM
I understand what you're trying to say about under powering a subwoofer, but you may want to rephrase with greater headroom. The way you've written it sounds like playing at low volume will kill a sub... Not the case :rollside:
Ok, here's the lowdown on how speakers and amplifiers work together...
An amplifier's damping factor is how well the amplifier can control the speaker. It does so by reversing polarity. By sending a pulse of electricity linear to the leads (positive to positive and negative to negative), the speaker is pushed outwards. Then that pulse is reversed, positive to negative and negative to positive, and the speaker pulls back into itself. Now remember that these pulses are actually taking place between 10 and 30,000 times per second (10 Hz - 30 kHz), so it's pretty critical. How well the amplifier can do this is rated in a specification called 'damping factor'. As an amplifier's output increases, this damping factor gets worse (it's not linear, but for example's sake let's just say it is). So imagine a small 200 watt amplifier trying to power a 15" sub with a 1000 watts RMS, the amplifier has to try it's hardest to move that sub, throwing out the window all ability to control the sub. As a result you get very sloppy cone movement, kinda like a piston rattling around in the cylinder wall of an engine. We all know what that does, it blows the motor. Exactly in this case, the speaker's motor assembly gets overheated from the added friction, and voila, the speaker is now damaged. Let's add in another factor... cooling. Let's say the added heat doesn't damage the speaker, it survives, because it can handle 4000 watts! But when you shut the system down, the motor assembly cools down so rapidly that it worps! Same thing happens when your car is overheated but still runs, once you shut it down, good luck getting it to start again.
Hope that clarifies things.

Magic34
08-30-2004, 07:16 PM
Ummm, so last time I was at the lake and playing the system, it got hot and in the cooling process, it got jacked up causing my problems that I have now?

B-Ron
08-30-2004, 07:34 PM
Ummm, so last time I was at the lake and playing the system, it got hot and in the cooling process, it got jacked up causing my problems that I have now?
From the info you gave me, that is definately a possibility.

ROZ
09-03-2004, 03:05 PM
I think the DF is one of those buzz words..... I know that it's a measured spec, but I don't think a person could audibly tell the differece solely based on a high vs low spec given all things are exactly the same....
I'm pretty sure that there are tests that have proven so, as well. Most amps good amps whouldn't have a problem controlling the driver...
I think that there are other factors that are much more criticle when designing an SQ vehicle.

Havasu Hangin'
09-03-2004, 06:08 PM
I think the DF is one of those buzz words..... I know that it's a measured spec, but I don't think a person could audibly tell the differece solely based on a high vs low spec given all things are exactly the same....
I'm pretty sure that there are tests that have proven so, as well. Most amps good amps whouldn't have a problem controlling the driver...
I think that there are other factors that are much more criticle when designing an SQ vehicle.
Shockingly enough...I agree with Roz. "Damping Facor" is a voodoo buzzword, with no audible difference in amplifiers.
Anyone speaking about DF is probably trying to sell you something.
http://groups.google.com/groups?q=damping+factor&hl=en&lr=&ie=UTF-8&selm=2rvv75%24tji%40introl.introl.com&rnum=1
http://groups.google.com/groups?q=damping+factor&hl=en&lr=&ie=UTF-8&selm=2rg06f%24100o%40introl.introl.com&rnum=2
http://www.trueaudio.com/post_013.htm

B-Ron
09-03-2004, 06:41 PM
You guys are right, it is one of those buzz words that salesmen pitch at customers. It was really big in the 90s, every amp manufacturer used it as a spec.
Just to clarify, I wasn't emphasizing DF's importance, I just used it to better clarify what I meant when I said underpowering a sub will blow it. I agree DF is a useless spec. The only time DF has any significance is when you've run into a problem. Like underpowering a sub (which is also overloading an amp). Or when amps overheat. But who cares how well your amp plays when it's about to go into protect mode.

Havasu Hangin'
09-03-2004, 06:51 PM
...what I meant when I said underpowering a sub will blow it.
How can underpowing a sub blow it?

riverbound
09-03-2004, 07:01 PM
How can underpowing a sub blow it?
Ususally when you under power a sub the distortion levels are going to be significantley higher and when speakers play at high distortion levels the speaker life seems to be shortened. In the experiences I have had it seems it is always better to overpower than underpower. You can always turn too much down, but cant turn too little up.

Havasu Hangin'
09-03-2004, 07:17 PM
Ususally when you under power a sub the distortion levels are going to be significantley higher and when speakers play at high distortion levels the speaker life seems to be shortened. In the experiences I have had it seems it is always better to overpower than underpower. You can always turn too much down, but cant turn too little up.
But when you underpower a sub, it has no ill effects.
A sub is nothing more than an AC motor. One of the few ways to kill an AC motor is to overheat it. Since you are putting less watts to it, there is no way for it to surpass it's thermal design limits, right? Even distorted.
A speaker does not know if it is playing music or distortion...they are the same to the motor.
Now, if you are talking about clipping an amp (like when an installer sets the gains to give the customer the capability to clip the amp), and that causes the speaker to recieve watts past it's design limits...then it can overheat the motor.
However, it was too much power that killed it...not enough.
I agree that overpowering subs tends to blow them less. However, that is usually because they are recieving less watts than perhaps a lower output amp driven into clipping, by a loose nut on the gain control.
But I'm an idiot, so consider the source.

ROZ
09-03-2004, 11:07 PM
I agree that overpowering subs tends to blow them less. However, that is usually because they are recieving less watts than perhaps a lower output amp driven into clipping, by a loose nut on the gain control.
But I'm an idiot, so consider the source.
I agree with the Idiot, but I guess it takes on to know one :jawdrop: It's more like overdriving the underpowered amp vs. not enough power for the speaker :D

Havasu Hangin'
09-04-2004, 03:56 AM
It's more like overdriving the underpowered amp vs. not enough power for the speaker :D
I couldn't have said it better myself. :idea:

rivercrazy
09-06-2004, 04:11 PM
Distortion does not kills subs, clipping an amp and forcing the Voice Coil to the stops is what creates heat in a sub and kills them.
That 2200.1 amp is definately a higher end amp. IMO its one of the better amps on the market. To date those GTi's subs are the best I've heard. Even better than W7's....
I'm sure with a little diagnosis, you'll get to the botom of the problem

Magic34
09-08-2004, 03:40 PM
Seems to be a problem with the charger charging the batteries. Tried wiring them a different way, and I'll check again tomorrow. If it doesn't work, I think the charger may be toast.

PHX ATC
09-08-2004, 04:05 PM
Scrap that whole entire piece of shit stereo and send it to me for destructive analysis. Put something worth a few dollars in there, quit being a tightass about the boat stereo thing. :p
Matter of fact scrap the entire boat and bring it over here for destructive testing. Get the 44', it's got more room for more stereo stuff. :D

Magic34
09-08-2004, 05:13 PM
Scrap that whole entire piece of shit stereo and send it to me for destructive analysis. Put something worth a few dollars in there, quit being a tightass about the boat stereo thing. :p
Matter of fact scrap the entire boat and bring it over here for destructive testing. Get the 44', it's got more room for more stereo stuff. :D
You got a deal, but I have no luck convincing the wife of that one. The boss has to sign off on that one, so bring your pen and best shirt and tie.

PHX ATC
09-08-2004, 06:37 PM
I don't own a tie, so my very best Hawaii shirt is being drycleaned as we speak. Should I set up an appointment with her? Since "cabin boy" can't schmooze it by her? :p :p :D
Let me know what the charger does with the rest of the stereo. I hope that's the culprit.

Magic34
09-13-2004, 08:38 PM
OK, well I feel like a jacka$$ right now.....
I am testing the system tomorrow after it has had many of days on the charger. The problem, at least what I think, is that all the water in the 6V batteries was nearly gone. Mind you, I just had them installed new at the end of March and I have only used my boat 5-6 times all summer, so I figured that could not have been the problem, but I think it was.
With the exception of a blown sub, everything else checks out OK. Each battery took a lot of distilled water, SO now I will check the batteries every month or so during the season.
My advice to 6V Trojan owners, check your stuff on a regular basis during the summer. All 6 of mine took a lot of water. Based on the amount the batteries took, I need to add water every other month for sure.
Hope this helps someone down the road.
Up until this point the 6V Trojan set up has been flawless for me,

PHX ATC
09-14-2004, 06:21 AM
Oh, so I suppose the boat won't be parking in front of my house anytime soon for "diagnosis?" :D
Glad you got her figured out.