Those with subs in their FRS.
 

How did you get the third break light above the back seats to stop ratteling.

Did you try deadening it from the trunk or from the back seat?

What did you use?

Thx

Currently running the Infinity Basslink, no rattle yet... *Knocks on wood*.

Try sticking some dynamat under the rear deckÉ For 20$ for a square foot it is worth a try I would say.

Hey Liquid, I got some sheets of Damplifier Pro (sold by Second Skin directly from their website), and followed this DIY to http://www.ft86club.com/forums/showthread.php?t=10002

When you get the rear deck off, lay the Damplifier Pro across the whole thing, tucking it with a roller (trust me, buy the roller. It looks like a mini dough roller. You need it. You'll thank me later!)

and poke holes for all the mounting things. The sides are pretty much symmetrical so just keep one side of the deck uncovered while you do the others, and look at the holes at the un-covered side for reference when poking through. Only thing you need to be aware of is the ground for the electronic locking box on the driver's side. Other than that, symmetrical and EZ PZ.

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I have a JL 12" W6V2 powered by a 1000.1 amp in the back... needless to say I found every single rattle. This rear decklid deadening took care of a good three quarters of the rattles. The other sources are the plastic panels to the sides, and the underlighting tray in the trunk. Surprisingly trunk doesn't rattle much.

Good luck, PM me with any Q's

Sound deadening is a must with a sub in the trunk. I use B-Quiet and RaamAudio. They are both good quality and cheaper than Dynamat products.

And as stated before, buy the roller! It will make the adhesive and material conform better to the shapes and lines of where you are applying it too.

Tada.

http://www.ft86club.com/forums/showthread.php?t=68048

Did this a few months ago, no more rattle, and its a lot easier than pulling the rear deck.

You guys are fkn awesome

Mine was rattling because of contact between the housing and the window. I ran a thin line of adhesive felt across the contact points.

I tried that actually, and there were still significant rattles. Might be my sub or a one-off, but I had to take apart the whole rear deck to stop the rattles!

Thank you though for being a pioneer. Was the first mod I did to try and quell the horrible noises whenever I turned the gain up

Well it helps that i only have a 10" JL with a 300W amp lol

I'm thinking of downgrading to a 250.1 and 10w3.. the cabin is pretty well off & I only run half or less gain most days. I could put the money from the 12w6 and 1000.1 into the suspension also :)

OP def give Pope's fix a try before taking the rear deck off, it's a looot easier :thumbup:

Sound deadening isn't for stopping rattles. It might work but it'll cost you a crap ton more than using the correct item. Go buy some foam. Yes, foam. Put that between the rear deck and the rear deck cover. It'll cost you maybe $10 and will work better than $100 of any deadener. You may also be having an issue with the 3rd brake light actually hitting the back window. If that's the case, adhesive-backed strip foam will fix that.

I respect your apt name and agree foam is great. The rear deck has some items on it that foam may affect the deck's fitment.. if you ever get around to using foam to quiet that deck rattle hope it gets documented and shared around- could save people some moolah.

Sound deadener, when used in strategic places, can work to stop rattles 100%. Don't need to cover the whole thing in your choice of CLD. Just spots where washers, mounted objects (such as the key remote brain), pieces of trim are indeed rattling.

Same goes for license plates and other sensitive trim areas where the bulging foam is not feasible, but you can certainly add a layer of CLD over it :)

Tuning will also help a great deal. The stock door speakers work fine down till about 60-70hz so if you cross over your subs at 60hz low pass you eliminate an enormous amount of rattling just from that. (that worked for me, but my subs are connected to a baffle fiberglass'd directly to the sheet metal)

There is another advantage to crossing over at a higher frequency -- power handling. The excursion of a smaller speaker is limited; a subwoofer typically has a much longer available excursion. So if you cross over at about 80 Hz, you'll be able to play louder with less distortion.

The car cabin is not very big, so bass itself is coupled to the interior at a relatively high frequency (by high I mean in the low hundreds Hz range). Once you reach the point where the half-wave is longer than the longest dimension of the car interior, you are pressure loaded anyway. So cross over a bit higher and gain some dB's at no extra cost.

Added: A 100 Hz wave has a wavelength of 11.3 ft. Therefore a half-wave is 5.65 feet long. That is probably just short of the total cabin length of the FR-S. This becomes 22.6 feet at 50 Hz (1/2 wave = 11.3 feet, which easily exceeds the cabin length). Once the wave is coupled to the interior as a pressure wave, there is no directionality; the sound seems to come from everywhere. The higher the crossover, the less the door speakers will rattle because of greatly reduced excursion. You are limited by the upper frequency response of the sub of course.

Try this: change the crossover to 100 Hz. If you can tell where the bass is coming from, lower the frequency to 80 Hz. Keep lowering the freq until you can no longer tell where the bass is coming from. Bear in mind that you have to trade off the bass quality with the door rattle caused by those speakers. Good luck!

There are a number of FR-S/BRZ builds on diymobileaudio.com that show it. You don't need a lot and it doesn't have to be thick to be effective. When I get home I'll put up a few links. When I do my build I'll have a log here as well as on DIYMA for everyone to criticize. :D:D

Sound deadener can absolutely stop rattles, but it's much more expensive way to do it is all I'm saying. Trust me, mine will have PLENTY of deadener. Just not in areas that are rattling. Well, at least not by itself.

For my plate I used something adhesive-backed weatherstripping foam from Lowe's. Works beautifully and compresses very nicely. Only down side is that only have 2 holes instead of 4 to screw the plate down and that bothers my OCD. :(

Those with subs in their FRS.
 

I hadn't thought about this, but it's true. I redid my "tune" with the OEM EQ and the doors and midbasses sound SO much better. I'll try to remember to post the pic of the settings later.

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