JL Subs Keep Blowing

[Big Block Power]

Hey sheriff are both subs next to each other? I thought 1 was in the head?

Where I don't see any! You get a discount on those!
So now I'm almost with Jeef on this. Did they run the wires parallel to make it louder?

[bruceb58]

We will give him the benefit of the doubt...but I would check the gain and crossover levels on all the outputs on both amps.

No need for an external crossover filter. The amp already has a built in Low Pass filter. If it's the one I posted above.

[NautiGirl]

We will give him the benefit of the doubt...but I would check the gain and crossover levels on all the outputs on both amps.

No need for an external crossover filter. The amp already has a built in Low Pass filter. If it's the one I posted above.

I know - perhaps I didnt word that well, I would check the frequency filter on the built in LPF and would also make sure the LPF is enabled as it is possible to disable it on that amp.

Still think the amp gain isnt set right but if they messed that up I would go over everything on both amps.

[NautiGirl]

Hey sheriff are both subs next to each other? I thought 1 was in the head?

Where I don't see any! You get a discount on those!
So now I'm almost with Jeef on this. Did they run the wires parallel to make it louder?

The M600/1 is a mono amp with two sets of parallel outputs. You can power one sub with it or two. If you use both sets of outputs the subs are wired in parallel.

[bruceb58]

Still think the amp gain isnt set right but if they messed that up I would go over everything on both amps.

That's my thoughts too.

[xlint89]

1. The installer stating he turned the amp down, concerns me. The amp cannot be turned down, the gain control can. That is not an amplifier volume control as the others noted. It's only meant to balance the amplifier input signal to the head unit output signal. Red flag number 1

2. Does the subwoofers being used in that orientation have "IB" in the model number? Meaning they are designed to be used in an infinite baffle application. (free air, no box) Which is what you are using in your set up. UNLESS you have some type of speaker enclosure or box I cannot see in your pic.

https://creativeaudio.net/m10ib5-cg-wh-kl/

If there is no "IB: in the model number, that speaker is meant to be used in an enclosure. Either sealed or ported. If they installed this speaker in that arrangement, it will definitely have problems. This speaker needs the air behind the speaker to act as it's suspension in order for it to not over extend. (flapping in the wind at high volume)

https://creativeaudio.net/m10w5-cg-wh/

If that's the case, then that would be red flag #2.

I have 2 of the M10W5 subs and the M600/1 amplifier just as you, and the amp is not overpowering the subs.

As noted, "clipping" or distortion is the main killer of speakers. But using the wrong type of enclosure for a specific speaker can also destroy a sub as well. Then you've got the wrong frequencies trying to be produced also. Subwoofer is meant to produce LOW frequencies. Say 30 to 200 hertz. anything above that, the speaker is just killing itself trying to produce a sound it was not designed to do.

I hope you can understand what I'm trying to explain.

Anyways, a picture of your amplifier settings might shed some light. Along with the exact subwoofer model number being used, and if you have a box of some sort they were installed into. (I don't think so, but just need to verify)

[sailor55330]

It's been a while since I played with mobile audio, but I think you have some great starts here. If the installer turned the gain all the way to "give it a kick", then he's not doing you a favor.... Also, as mentioned, check where the crossover frequency is. Personally, I've never crossed a sub over higher than 80hz because they start to sound muddy...Subs go boom, not squeal. 100hz would by my max tolerable setting. It would be like asking a bass singer to cover the soprano part....laws of physics do apply here.

One other thought---even though the amp is rated rated at 300wx1 @ 4ohms, that may be aggressive by JL for marketing purposes. It used to be that audio manufactures all wanted to be the big dog so they would see what the absolute peak they could get for a millisecond was then post it. The result usually ended up badly for the consumer. I see that the THD is <1% @ 2ohms, but it doesn't list anything for 4ohm installation (I think you're at 2ohm the way it's wired) so you're probably ok--but that also means you are pushing more power than what the subs are rated for. Now, with that said, I'll take too much clean power all day long (same as BBP's big block analogy).

Now, at looking at the amp online, if the speakers are wired in parallel (which I kind of suspect), then the resistance drops to 2ohms and the amp output jumps to 500wx1. No way the speakers rated at will handle that--they are rated at 250RMS. If the installer picked out this system, he should have known that. Couple that with a poor crossover frequency and a very high gain setting and you're going to have problems. That's my best guess. I'd be asking the installer some tough questions.

[xlint89]

As some of you know, we did a major stereo upgrade to our boat in 2019. The entire boat was re-wired, we added 6 new house speakers, 2 transom speakers, and (2) 10" subs. Everything is JL. The house speakers and transom speakers are MX ( the lower end speakers), but we chose them because we thought they sounded better than the M (higher end) series. The amps and subs are M series. All of this was installed a a very reputable shop here in town. We used the M series amps and subs at their recommendation. There are 2 subs. An M Series 800/8 runs the house and transom speakers. They all get 100 watts on their own channel, and the sound quality is amazing.

The subs are powered by a 600/1 JL amp. Right now the subs are out of the boat and being sent back to JL for the THIRD TIME because they keep blowing. I really don't know if they are being covered by the manufacturer's warranty, or the warranty the shop gave me for their installation (lifetime). All I know is every time I have had a problem, they fix it. I'm getting pretty tired of taking the boat to them to have them pulled out, putting it back in storage, taking the boat back to have the new ones installed, making it about half way through the season, and having 1 or both subs blow.

I've asked the installer how loud we should turn it up. The head unit goes to 40, and he said 30 should have no problems at all. If you've heard the system you know it is insanely clear and loud. After the second time I told him I was really tired of this whole process, I spent good money to get a kick ass system, and he needed to make it right. Supposedly he has turned the amps down twice now, but we are still getting the same result. I looked and these subs say they should not get more than (I think) 200-225 watts. The installer told me he has the amp turned down to about 50%, and last time he did something with the crossover that JL had suggested. Still blew the new speakers. I was just up there 2 weeks ago having the blown subs taken back out, and now we are waiting for JL to ship new ones.

The installer is a great guy, and I have NO reason to doubt that he knows his stuff. I just don't understand what is happening. I have the best marine subs JL makes supposedly. He talked about moving me up to 12" speakers, but those wouldn't fit where we have them mounted. I want the bass to rattle our teeth like it does now, but not if it is going to turn into this madness every year or more. I spent a pretty penny on this system, so the last thing I want to do is spend more money on it. What do I need to do to insure this gets fixed? What are some suggestions I can make to the installer? My brother said I should have them install some competition subs, but where they are mounted they definitely see some water from people climbing over them getting in and out of the boat. What do you folks think?

It's been quite a while since this was posted. Did you ever find a reason for the problem?