Installing JL M7 IB subwoofer in Helix

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This was pretty scary to do without pictures due to limited clearance so I figured I’d post what I did and see if it helps anyone.

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First, I used my router to cut a template of the surround. I then marked on it where the screws go and mounted my surround template

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While there has to be a better way, all I could think of was a Dremmel with a carbide tip attachment. I used this due to limited clearance for a router or jig saw. Took a bit as the Dremmel got hot and I’d have to let it cool.

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Turned out pretty good for the hole:

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And the final product:

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It is pretty loud, but lots of dash rattles. I’m going to mat it and have closed off some of the holes on the back of the dash with some success. I’ll get to looking with what people here did to solve that issue.

[SONIC]

I've had good luck with this stuff to knock down rattles
https://www.amazon.com/Noico-deadening-Automotive-Insulation-dampening/dp/B00URUIKAK/ref=sr_1_1_sspa?dchild=1&keywords=noico&qid=1598271483&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUFYNlVQWUJZVDZHQ1kmZ W5jcnlwdGVkSWQ9QTA2MzAzMDQxVzRISzhBVDc2T1MzJmVuY3J 5cHRlZEFkSWQ9QTA0NzE2MzAyNFNRQjFEQ1VZNDBKJndpZGdld E5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm9 0TG9nQ2xpY2s9dHJ1ZQ==

[sandm]

looks great...
hardest part is putting the first hole in the boat. gets easier now :)

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I've had good luck with this stuff to knock down rattles
https://www.amazon.com/Noico-deadening-Automotive-Insulation-dampening/dp/B00URUIKAK/ref=sr_1_1_sspa?dchild=1&keywords=noico&qid=1598271483&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUFYNlVQWUJZVDZHQ1kmZ W5jcnlwdGVkSWQ9QTA2MzAzMDQxVzRISzhBVDc2T1MzJmVuY3J 5cHRlZEFkSWQ9QTA0NzE2MzAyNFNRQjFEQ1VZNDBKJndpZGdld E5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm9 0TG9nQ2xpY2s9dHJ1ZQ==

Ordered today - May need some bracing too as dash moves a lot. What do you think about putting the 315 foam on top of the base later - know some auto guys doing the same 80mil you recommend then putting the 315mil rubber on top of that for more deadening.

[SONIC]

I haven't used the red but have read good things about it for sound deadening uses.
I don't know how much it will help for this though as you're not trying to block sound you're really just trying to stiffen the glass and absorb some of that energy before it gets to the glass.
Mass loaded vinyl may be a good option it's super dense and absorbs a lot of the energy of the sound wave vs stiffening the panel like the butyl stuff.

A little pricier though.

https://www.amazon.com/Loaded-Barrier-Square-Soundproofing-Acoustic/dp/B07Z6M63QC/ref=sr_1_12?dchild=1&keywords=mass+loaded+vinyl&qid=1598358002&sr=8-12#customerReviews

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Actually most the vibration turns out to be between the glass and the softer dash material. Some moderate density foam really dampened it well. May lay the vinyl on the front side, but really loud without rattles locally now - more distant things start to make noise of course.