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Discussion Starter · #1 · (Edited)
Does anyone know where they are located precisely on the sedan (or hatch)? I recall someone had opened up one of the vents as part of a sub install, but I can't find that post. Looking all over from underneath right behind the rear wheel well with a flashlight, I'm not seeing it anywhere.
 

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you appear to have posted images of the rear impact bar lol

here's the passenger side one in the gen 3:
281951

281952

i removed the top flap (circled in red)
 

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Discussion Starter · #4 ·
you appear to have posted images of the rear impact bar lol

here's the passenger side one in the gen 3:
View attachment 281951
View attachment 281952
i removed the top flap (circled in red)
The images show (not in blue) the vent locations I think, but this is what I was looking for, thank you!

I think I'll do the same. Sub is vibrating the bumper and bike rack like nobody's business.
 

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Discussion Starter · #6 · (Edited)
you appear to have posted images of the rear impact bar lol

here's the passenger side one in the gen 3:
View attachment 281951
View attachment 281952

i removed the top flap (circled in red)
I also might put some butyl underneath the gas tank lid's inner plastic mount. Not sure if the gen3 lid vibrates, but the gen4 lid has a noticeable rattle from the outside with some loud bass. I wouldn't be surprised if that was causing my earlier C-Pillar rattle that was predominantly on the driver's side.

281960
 

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Discussion Starter · #8 ·
share your thoughts on sub performance after you open up a vent :)
From the outside, my sense was that the rear bumper and bike rack vibrate a little less with 2 of the 4 flaps removed on each side. I've mostly tamed the gas lid with butyl, so between those 2 improvements, I'm hearing a lot less component buzz during bass hits. Nice find!
 

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From the outside, my sense was that the rear bumper and bike rack vibrate a little less with 2 of the 4 flaps removed on each side. I've mostly tamed the gas lid with butyl, so between those 2 improvements, I'm hearing a lot less component buzz during bass hits. Nice find!
so no increase in SPL/low extension?
I took out one and that solved the flapping/chuffing noise they caused, and i got higher SPL & lower extension.

I'd consider putting some of the flaps back and seeing if that changes anything. don't want to big of a "port" or you can actually lose SPL
 

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Discussion Starter · #11 ·
what's your sound deadening strategy here? it doesn't look effective tbh. putting in real stuff could help with rattles further
At the time it was rattles and dampening for the sub. I took out some of it this last time as I agree it's useless, though that was a pain. The deck is what I'm eying for rattle dampening. Do you have the sedan, I forget?
 

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Discussion Starter · #13 ·
what's your sound deadening strategy here? it doesn't look effective tbh. putting in real stuff could help with rattles further
I just realized that damn gas cap was the cause of all of that effort. C-Pillar vibrating sound.
 

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Discussion Starter · #14 ·
so no increase in SPL/low extension?
I took out one and that solved the flapping/chuffing noise they caused, and i got higher SPL & lower extension.

I'd consider putting some of the flaps back and seeing if that changes anything. don't want to big of a "port" or you can actually lose SPL
Not that I noticed, but I also had just flipped my sub to point back toward the rear, which gave a 5db boost. Are you talking about something you measured with an SPL meter?
 

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Not that I noticed, but I also had just flipped my sub to point back toward the rear, which gave a 5db boost. Are you talking about something you measured with an SPL meter?
it's just a rule of thumb when designing sub enclosures. small port = higher SPL but chuffing sound. big port = loss of SPL. way too big port = virtually open air/can damage the sub
and yes, the sub pointed at the rear usually gives the best SPL
 

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With flap removal, notice any increased exhaust or sulfur smell getting in-cabin?

Sent from my SM-G970F using Tapatalk
 

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Discussion Starter · #17 ·
With flap removal, notice any increased exhaust or sulfur smell getting in-cabin?

Sent from my SM-G970F using Tapatalk
I have not, but that and water penetration are 2 things to be mindful of, and the main reasons I'm only removing 2 of the 4 for the time being.

Maybe less useful for a sealed sub from what I'm reading. My goal was more related to avoiding bass-induced rattles, which corrupt the sound of music, IMO.

If it weren't such a pain to access, I'd run a few tests. My left side sedan trunk liner is starting to come apart from all the removals and re-installations.
 

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I have not, but that and water penetration are 2 things to be mindful of, and the main reasons I'm only removing 2 of the 4 for the time being.

Maybe less useful for a sealed sub from what I'm reading. My goal was more related to avoiding bass-induced rattles, which corrupt the sound of music, IMO.

If it weren't such a pain to access, I'd run a few tests. My left side sedan trunk liner is starting to come apart from all the removals and re-installations.
Yes, water is indeed a concern, too.

Sent from my SM-G970F using Tapatalk
 

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Discussion Starter · #19 ·
Yes, water is indeed a concern, too.

Sent from my SM-G970F using Tapatalk
Luckily, It's easy to peek at the passenger side vent by removing the access panel, so I'll keep an eye on it after some heavy NC rainfalls. I suspect it's more of an issue for pickup trucks and the like, but you can't be too cautious with this type of mod. If there's one thing I've learned about this car, it's that it's highly sensitive. To everything.
 

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Discussion Starter · #20 ·
The other thing to keep in mind is that you might be gaining SPL at one freq, like your deep bass, but sacrificing at others, like your highs, or particularly your mids, which are already anemic on the gen4s that only have those 3" door speakers up front for those frequencies. Less of an issue for the gen3s due to driver sizes and locations.
 
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