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Discussion Starter #1
I've never been satisfied with the bass in my car, which is a 2016 Chevrolet SS sedan. The rear seat blocks/absorbs a significant amount of the sound and I can be almost happy without the subwoofer even being there unless I was listing to something really bass heavy - and I'm usually listening to rock, blues, or country. I went from a 10" PSI to a 12" SSA Icon both ported and I think I also don't love the ported sound as much either for music. I built a down-firing sealed box to go between the second row seats in my Escalade for a GB12 and it sounds awesome. So I was thinking about trying to replicate that in my car. I think there's enough room behind the passenger seat to build a sealed box for a GB10. It'll be a little "complicated" because it'll need to be angled to allow the passenger seat to be comfortable. I'd like opinions on whether I should do this down-firing or have it front-firing into the back of the passenger seat. The down-firing will push the box height up ~2" or so to leave some breathing room.

The base can be up to 12" deep by 18" wide. The back can go straight up and can be up to 13.5" high without being taller than the rear seat bottom. At the top there is about 9" between the rear seat cushion and back of the passenger seat. I've attached some pictures of the space to help visualize.

Does this sound doable or a good idea since it will be directing the sound under the passenger seat if down-firing or into the back seat if front firing? Up-firing could be an option depending on how much space there needs to be behind the magnet but I like that down or front-firing will provide built-in protection for the speaker. I guess my other option would be to do a ported GB12D4 in the trunk and hope it sounds better than the SSA. It would be nice to have my trunk back though.
 

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In terms of space, you could fit an appropriate sized sealed box there, if you don't use the rear seat for passengers much... I would down fire it for sure - you have the needed size like that and it would be the safest place for the sub to be protected from hitting something or getting damaged.

However, I would consider making a box that would sit in the middle of the rear seat and extend down to the hump like a center console... If done right, this could look very nice, allow the rear seat to still be a comfortable 2 passenger seat and open up options like more volume, larger sub, ported, etc.. With what you've done in your Escalade, it sounds like you could pull this off pretty well.
 

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Is the back of the rear seat made of metal? You might want to investigate some. If metal, you could potentially drill holes to allow some sound through. If not metal and it is just dense foam in your seat, I might recommend looking at the SI RM-15, which will have a lot more output than a GB12 as it has more power handling and excursion. I think a single one in your trunk, assuming your back seat isn’t completely metal, would give phenomenal output and sound quality with a sealed enclosure near 2-2.5 cu.ft. A single RM-15 would likely be equivalent to 2.5 GB12s so we’re talking significantly more bass. And that is not a knock on the AF GB sub as those are very good. This would allow you to use your car as a more traditional car, while still having plenty of bass.
 

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Discussion Starter #4
In terms of space, you could fit an appropriate sized sealed box there, if you don't use the rear seat for passengers much... I would down fire it for sure - you have the needed size like that and it would be the safest place for the sub to be protected from hitting something or getting damaged.

However, I would consider making a box that would sit in the middle of the rear seat and extend down to the hump like a center console... If done right, this could look very nice, allow the rear seat to still be a comfortable 2 passenger seat and open up options like more volume and ported, etc..
The back seat has only ever had my son’s car seat in it a couple times otherwise no one has ever been in the back. I occasionally have a front seat passenger which is why I wasn’t wanting to push the front seat up too much. Worst case it’ll be easily removable with a connection on the wires.

I had considered doing a box that sat in the back seat but I don’t want to do anything that will hurt the leather or leave impressions.
 

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What happened here? The posts disappeared...
 

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What happened here? The posts disappeared...
The post i thought i made here ended up in my tweeter sale listing. And so did the OP response LOL.

I was just saying "test" the GB12 box in the new car, just to get an idea of how the downfiring GB10 might sound.
 

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If I go through my posts, it shows correctly but when visiting his thread from the list of threads, my post is missing.
 

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The post i thought i made here ended up in my tweeter sale listing. And so did the OP response LOL.

I was just saying "test" the GB12 box in the new car, just to get an idea of how the downfiring GB10 might sound.
LOL

That could be confusing... People might think your are recommending down-firing your tweeters! :p
 

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The back seat has only ever had my son’s car seat in it a couple times otherwise no one has ever been in the back. I occasionally have a front seat passenger which is why I wasn’t wanting to push the front seat up too much. Worst case it’ll be easily removable with a connection on the wires.

I had considered doing a box that sat in the back seat but I don’t want to do anything that will hurt the leather or leave impressions.
I think it could be done with no damage to the seats... Maybe secure it to the hump or under the seat and cantilever just over the seat so it isn't even touching. :D
 

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Discussion Starter #10
Is the back of the rear seat made of metal? You might want to investigate some. If metal, you could potentially drill holes to allow some sound through. If not metal and it is just dense foam in your seat, I might recommend looking at the SI RM-15, which will have a lot more output than a GB12 as it has more power handling and excursion. I think a single one in your trunk, assuming your back seat isn’t completely metal, would give phenomenal output and sound quality with a sealed enclosure near 2-2.5 cu.ft. A single RM-15 would likely be equivalent to 2.5 GB12s so we’re talking significantly more bass. And that is not a knock on the AF GB sub as those are very good. This would allow you to use your car as a more traditional car, while still having plenty of bass.
There is a metal frame but the foam itself is very insulating. When I installed the original system, I drove around with just the seat bottom out because I was still running wires and the amount of extra road noise was substantial, which surprised me for just being the seat bottom.

Part of my idea for doing this is to get my trunk back which I use far more than the back seat - I don’t know if it was one of the posts that disappeared but the back seat has only been used less than 5 times with my son’s car seat. Since kids are supposed to be in car seats until they get driver’s licenses, I’m thinking it won’t be a problem. There’s still the seat behind the driver.
 

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passenger foot well :p
 

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There is a metal frame but the foam itself is very insulating. When I installed the original system, I drove around with just the seat bottom out because I was still running wires and the amount of extra road noise was substantial, which surprised me for just being the seat bottom.

Part of my idea for doing this is to get my trunk back which I use far more than the back seat - I don’t know if it was one of the posts that disappeared but the back seat has only been used less than 5 times with my son’s car seat. Since kids are supposed to be in car seats until they get driver’s licenses, I’m thinking it won’t be a problem. There’s still the seat behind the driver.
If it is just foam, even a 12” sub should fire through it with little issue. The wavelengths are so long that it is very hard to contain bass, you pretty much need concrete in a house or 3 sheets of drywall. I’m big into home theater and supply subs for several home theater designers.

https://www.acousticfields.com/wavelengths-in-our-rooms/

Road noise is definitely at a higher frequencies than bass waves, which is why the rear seat blocks it so well. And the higher the frequency, the easier it is to attenuate the sound, meaning frequencies above 2,000 Hz can be easily attenuated by maybe 1” of foam while you’ll need many more inches to attenuate midbass frequencies and you may need multiple feet of foam to attenuate deep bass frequencies.

I think a single sealed RM-15 would have no trouble going through the seat and providing copious amounts of bass and would only need 2-2.5 cu.ft. powered with 1200-1500w. That’s what I would do in your situation. I’m going to be putting a single RM-12 in my car to fire through the rear seat though I originally ordered a single RM-15.
 

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Discussion Starter #13
You’re right, it probably would be plenty (and awesome) but it definitely wouldn’t give me my trunk space back. I’m actually not even sure an enclosure for that would fit in my trunk since I have the amplifier and DSP mounted to the underside of the package tray inside the trunk.

I just realized I put GB12 in the thread title when I meant GB10, I guess everyone got what I meant from reading the post.
 

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Discussion Starter #14
How much space needs to be behind the magnet? I searched on here and found anywhere from 1/2 the pole vent diameter to 5.” I saw the most answers saying the diameter of the vent.

I realized I can do a front firing box much easier because there won’t be an angle to deal with so I’m leaning that route. If I do a 17” x 12” x 9” then it’ll be a hair under .6 cubic feet and have 1.25” behind the magnet.
 

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How much space needs to be behind the magnet? I searched on here and found anywhere from 1/2 the pole vent diameter to 5.” I saw the most answers saying the diameter of the vent.



I realized I can do a front firing box much easier because there won’t be an angle to deal with so I’m leaning that route. If I do a 17” x 12” x 9” then it’ll be a hair under .6 cubic feet and have 1.25” behind the magnet.
You could theoretically go as close as 1/4 of the vent diameter, but I'd say stick with the vent diameter spacing for safety.
 

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Discussion Starter #16
I finally got this done and installed over the weekend. I did end up going front firing for ease of building the enclosure. I haven't driven the car yet but I did a rough modification to the tune and listened to a few songs and it sounded really good. Obviously, it still has to break in so it should sound even better. Definitely a HUGE weight savings also and I get my entire trunk back!
 

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