Did this poor install lead to my speakers blowing??

[Ijcobra 10+ year member]

I recently blew 2 JL Audio ZR-800 8" midbass speakers in custom fiberglass door panels on a '06 Jeep Grand Cherokee SRT-8. After the installer removed the speakers to send them to JL Audio for repair, I finally was able to see how the install actually looked behind the speakers and I am very concerned. See photos.

These were powered by bridged channels of a JL Audio HD900/5 amp (~150 watts) and controlled via a Rockford Fosgate 3Sixty.3 DSP bandpassed between 80Hz-300Hz (24db Linkwitz-Riley crossover).

You can see the ZR-800 speakers mount to the passenger compartment side panel of the door in custom fiberglass. Unfortunately, the speakers are only using the airspace between the passenger compartment panel of the door to the first interior panel (basically, the window tract). The large cavernous interior volume behind the window tract to the outside of the door (exterior of vehicle side) is not being used at all due to a "wall" of Dynamat filling the hole that would be there (where the factory speaker mounted). You can see where I tore a hole into the Dynamat in the photo where the back of the speaker butts against it the Dynamat causing a circular impression.

I think this installation is causing at least 2 problems which led to my speakers blowing:

1. Not enough interior volume!

2. The flexible Dynamat "wall" caused attenuation of the speaker by moving in & out of phase with the speaker's movements, limiting output HUGELY and necessitating me cranking up the gain... which led to the speaker blowing.

The speakers in this installation never particularly impressed me, and were not at all an improvement from my previous 6.5" CDT speakers which were installed in factory locations prior to this.

Here is a video:



Automotive Concepts in Minneapolis did the install and has sent both speakers back to JL Audio for repair. They are charging me $95 for each speaker (claiming this is what you charge), plus 15% on top of that, plus $30 for un-install plus $30 for install, plus $15 for shipping. This is on top of the $2000 I already spent on the initial installation.

What do you think?

Click to read more...

 

[LosIsATool 5,000+ posts]

You cranking the gain is why they blew. The install may kill preformance.

 

[adulbrich 5,000+ posts]

I recently blew 2 JL Audio ZR-800 8" midbass speakers in custom fiberglass door panels on a '06 Jeep Grand Cherokee SRT-8. After the installer removed the speakers to send them to JL Audio for repair, I finally was able to see how the install actually looked behind the speakers and I am very concerned. See photos.
These were powered by bridged channels of a JL Audio HD900/5 amp (~150 watts) and controlled via a Rockford Fosgate 3Sixty.3 DSP bandpassed between 80Hz-300Hz (24db Linkwitz-Riley crossover).

You can see the ZR-800 speakers mount to the passenger compartment side panel of the door in custom fiberglass. Unfortunately, the speakers are only using the airspace between the passenger compartment panel of the door to the first interior panel (basically, the window tract). The large cavernous interior volume behind the window tract to the outside of the door (exterior of vehicle side) is not being used at all due to a "wall" of Dynamat filling the hole that would be there (where the factory speaker mounted). You can see where I tore a hole into the Dynamat in the photo where the back of the speaker butts against it the Dynamat causing a circular impression.

I think this installation is causing at least 2 problems which led to my speakers blowing:

1. Not enough interior volume!

2. The flexible Dynamat "wall" caused attenuation of the speaker by moving in & out of phase with the speaker's movements, limiting output HUGELY and necessitating me cranking up the gain... which led to the speaker blowing.

The speakers in this installation never particularly impressed me, and were not at all an improvement from my previous 6.5" CDT speakers which were installed in factory locations prior to this.

Here is a video:

The install may not be fantastic, but if you cranked the gain, it's your fault that they blew.

The install did not blow your speakers. You did.

 

[LosIsATool 5,000+ posts]

I had those before. They are monsters but the install has to be on point. Door frames braces and ccf everywhere.

 

[Ijcobra 10+ year member]

The install may not be fantastic, but if you cranked the gain, it's your fault that they blew.
The install did not blow your speakers. You did.

While the crappy install by itself did not cause the speakers to blow, the completely inadequate and disappointing Midbass performance caused by the crappy installation caused me to do the only thing left to do: increase the power (by decreasing the signal attenuation from -15dB to -6dB from DSP to amps).

 

[wew lad 5,000+ posts]

While the crappy install by itself did not cause the speakers to blow, the completely inadequate and disappointing Midbass performance caused by the crappy installation caused me to do the only thing left to do: increase the power (by decreasing the signal attenuation from -15dB to -6dB from DSP to amps).

how is that the only thing left for you to do? clipping your equipment is not a thing on any list..

 

[Ijcobra 10+ year member]

how is that the only thing left for you to do? clipping your equipment is not a thing on any list..

What was the next step? Perhaps the Midbass needed more gain overlap?

Forking over a lot of money for "the best" install with "the best" (or close) equipment at "the best" (and biggest) installer in the Midwest only to get turdy Midbass is insane and unacceptable. I was assured it wasn't the install or equipment... That just leaves the tune.

 

[murph 10+ year member]

Wow!

Well first off you were putting too much power to those speakers. If you are a novice I would stay 10% below rated power on the door speakers. JL had them rated at 125 rms at the most, while you ran them with 150 watts.

If your gains weren't set right as well and you were clipping that would be another culprit. Also if you used any type of boost aka raise the mid bass.

You also could have had the volume up past the head units clean signal range.

Finally and most likely a small part of the cause was having no space for the speaker. This could have possibly over extended the speaker.

 

[adulbrich 5,000+ posts]

While the crappy install by itself did not cause the speakers to blow, the completely inadequate and disappointing Midbass performance caused by the crappy installation caused me to do the only thing left to do: increase the power (by decreasing the signal attenuation from -15dB to -6dB from DSP to amps).

You messed with their settings. That's not their fault, it's yours. If you were unhappy with the performance, you should have voiced your concern.

Judging by the fact that you paid to have your install done, you should not have messed with it. That is not the best equipment, contrary to what you might believe.

 

[Ijcobra 10+ year member]

Wow!
Well first off you were putting too much power to those speakers. If you are a novice I would stay 10% below rated power on the door speakers. JL had them rated at 125 rms at the most, while you ran them with 150 watts.

If your gains weren't set right as well and you were clipping that would be another culprit. Also if you used any type of boost aka raise the mid bass.

You also could have had the volume up past the head units clean signal range.

Finally and most likely a small part of the cause was having no space for the speaker. This could have possibly over extended the speaker.

No. According to JL's manual for these speakers:

Infinite Baffle (which is what I was told these speakers are installed as):

As a dedicated mid-bass speaker operating

above 50 Hz (with active filtering) the

ZR800-CW can be safely operated at

power levels momentarily exceeding 200

watts per woofer. When operating below

50 Hz as a true woofer, power should be

limited to no more than 125 watts per

woofer in infinite baffle applications.

Yes I am running active and crossed over between 80-300Hz at 24db LR (sometimes to 350Hz; I adjust a lot because the sound ***** and I try to make it better).

My DSP tells me my headunit is good until 37 out of 40 on volume, so I do not exceed that.

I never use any sort of bass boost/loudness/etc.

Knowledge check: when you say 125 or 150 watts, is that at 0db attenuated input signal? Is that at 3/4 volume on the headunit, or at the point of clipping (37 in my case)? What amount of gain overlap do you recommend on these midbass drivers in this application?

 

[Ijcobra 10+ year member]

You messed with their settings. That's not their fault, it's yours. If you were unhappy with the performance, you should have voiced your concern.
Judging by the fact that you paid to have your install done, you should not have messed with it. That is not the best equipment, contrary to what you might believe.

They did not perform any sort of tuning. I do all my own tuning (and I did use a multimeter, have an o'scope, and am very experienced with the process). I also do not believe in this process in setting gains anymore. It's BS. I now use this method: Amplifier gain controls - setting your gain and my fully-active powered tweeters, midrange, and subs are fine.

I believe the install caused all these problems; specifically the "Dynamat wall". Imagine a speaker box build to only 33% of optimal size, and with an entire side made of Dynamat. That is what I have! Can you imagine all the problems this would cause? Extreme temperature variances as Dynamat is way more pliable in hot than cold (summer vs. winter here in MN). I could never get good sound from the midbass, and had huge dead zones in the frequency response which were different per side (say 160hz one side and 220 hz the other). Sometimes they sounded ok others bad bad. And never better than my previous 6.5" CDTs in the factory locations.

As far as ZR-800's not being the best: there is no best. But they are quite adequate IF installed correctly. The search for the best woofer is a case of diminishing returns... especially in mobile audio.

 

[Ijcobra 10+ year member]

how is that the only thing left for you to do? clipping your equipment is not a thing on any list..

No. Clipping is a thing on lists. It's recommended by Rockford Fosgate and anyone who actually wants their MUSIC (not test tones) to sound good and loud!

How to Properly Set Your Gains (Gain Tutorial)

I've tuned with no Gain Overlap and it *****. It's completely adequate for my grandma tho.

 

[SounDrive Pro Seller]

You blew the speakers, not the install. Having them installed like that would most definitely sacrifice midbass and limit excursion however cranking up the gain was not the proper approach.

Did you check with your oscope to make sure your signal wasn't clipped after you cranked it up?

In the end you messed with the settings after the shop installed it so it is in no way their fault.

 

[LosIsATool 5,000+ posts]

The ZR800s are tough to beat as a midbass. They will shake your doors apart if the install is off.

I had 150rms per mid but I'm not a tard.

 

[Ijcobra 10+ year member]

You blew the speakers, not the install. Having them installed like that would most definitely sacrifice midbass and limit excursion however cranking up the gain was not the proper approach.
Did you check with your o'scope to make sure your signal wasn't clipped after you cranked it up?

In the end you messed with the settings after the shop installed it so it is in no way their fault.

In no way their fault? Yet the only possible way to fix the midbass (once my speakers are repaired and re-installed) is to un-do their installation method (ie: remove the Dynamat wall). Hmmmm.... I'm not sure I fully follow this logic.

I'm sure with the Dynamat wall removed the speakers will perform nicely (with much less gain required as well).

Oh I see the guy who was submerged for an hour in a sealed chamber full of water shouldn't have breathed the water! Duh, he was an idiot. No wonder he drown.