:welcome: to the Forum..:wavey:

 

While you will hear some people who have added "underseat subwoofers" on the forum and are happy with them, they tend to get drowned out pretty easily. In a vehicle with a high noise threshold like a Jeep, I would suggest going other routes myself.

There are three main things which allow a subwoofer to produce realistic levels of bass- amplifier power, cone area, and excursion. Underseat subwoofers have limits on all three of these factors. You can sometimes shoehorn a traditional 8" or 10" woofer that was designed to be used in a compact enclosure under a seat, but enclosure size and aiming have a lot to do with how well that bass loads the cabin of the vehicle...putting it under a seat further hampers a woofer's output.

Whether one of those self-powered underseat woofers works for you or is a waste of money will depend on your expectations on volume level and sound quality. I'd consider a traditional good quality sub, a custom enclosure built to the needs of the woofer and a separate amp. If that will infringe too much on your cargo area, you could consider the 2015 and newer factory Alpine sub, and add a separate aftermarket amplifier for it- it isn't that bad (and likely better than 99% of the underseat powered sub options), and takes next to no cargo space.

 

I just installed a Kenwood KSC-SW11 under the passenger seat of my JK. It was a pain to mount as I had to make my own brackets and such but it sounds great.

 

How do you like it? Where did you end up connecting your ground wire? Also, where did you poke through your firewall to get to the battery? I've noticed a lot of people using the foamed passthroughs on the either the passenger/driver side, but I've also seen a mention of a rubber grommet passthrough under the driver dash near the brake pedal.

I ended up ordering a VPAS10 and am planning on installing under the passenger side seat as well. I already received my amp kit ahead of the sub, so I'm hoping to have a solid strategy in place so I'm not spending hours later. Thanks for the feedback!

 

@PSJKU16 I like it. Really fills the sound out. I ran the ground to the nearest chassis ground that was being used by some other things and ran the power wire through the rubber grommet by the brake pedal. It's the same grommet I've used for other wires, including my switch panel

 

I have a Rockford Fosgate PS8 powered sub for my 2 door , hard top wrangler sport. I LOVE IT... I too have upgraded the speakers, front, rear and tweets- this little sub rounds out my sound- top on/off- it's night and day difference. I just have it mounted on the floor behind the drivers seat. My jeep is a dedicated 2 seater, as we took out the rear seat. and it stays out. Again- some say these add on powered subs are not any good. I'd challenge anyone to say there isn't a bunch of whoomp to my music now. worth the couple hundred dollar investment. Also, I tied the PS8 into the rear speakers via some module I inserted inline to the rear speaker wire.

Power wire ran up along driver side door thru firewall and into engine
Ground Wire is in the back of jeep near the "well" under the carpet/storage area. perfect spot and well grounded.
It's "remote" turn on fyi-

 

@AirForceAngler the chassis ground that you used, is this the ground located to the left and right of the center console? I was planning on using that as a ground but also heard that those two ground locations are for airbags and not recommended. Not sure if that's true or not.

The only other location I was thinking of was to use the rear bolt that secures the passenger seat. If you have any pics you can post of your ground location, that would be awesome! If not no worries.

 

I'll have to go out to the shop (where the Jeep is) and look later, but I think I used the first ones you mentioned. Not sure why this would be bad or why the airbags would be grounded there. Too many other places under the dash for airbag grounds. I'll try to get a pic but it was a tight location to work when I installed everything.

 

@Sands611 I feel the same way you do. I'm not looking to wake my neighbors and shatter windows. I simply want a little more overall balance and be able to feel what I'm listening to from within the cabin. I feel like these underseat subs help fill that current void in my setup.

I remember renting a 2016 Sahara down in Miami this past year and it had the Alpine premium sound system. When I recently purchased my 2016 JKU Sport a few months ago, I couldn't help but immediately notice how awful the stock non Alpine setup sounded. Thx for sharing my friend.

 

Just to put things into perspective, my tastes and previous systems weren't built to wake neighbours or shatter windows- I was after realistic and balanced bass output. It usually takes a couple of extremely large woofers in a ported enclosure (think "most of a JKU's cargo area") with a lot of clean power behind them to accomplish levels of output that get noticed, which has never been a goal of mine.

I am an "SQ" guy, and that usually means a system that sounds similar to a good home reference system rather than a noisemaker...a single 10" or 12" traditional woofer of good quality installed in a custom enclosure with modest amounts of power driving it will achieve that realistic bass response, without disturbing the peace or being noticeable outside of the vehicle. While a self-powered underseat sub will certainly play some lower frequencies, IMHO it is the wrong tool for the job for my purposes as they tend to roll off the lowest frequencies and lack output to sound realistic. I personally know many people who have gone that route and have been disappointed. Whether you will be happy with one remains to be seen.

 

All good @basicxj and hear where you're coming from. In your opinion, how would you compare the sound coming from the sub on the JKs with the Alpine premium sound system vs one that utilizes an underseat sub?

I would imagine based on woofer size, the fact that both utilize rather small enclosures, and not a ton of power behind them, they would be rather comparable in performance? Thx for the feedback!

 

I would rank the factory sub as "not bad" for what it is and the power you'd need to run it, and great for the space it requires. Is it awesome? No, not compared to something like a good aftermarket sub (or even a JL Stealthbox) powered by a proper amp, but the factory sub certainly digs fairly low for what it is, and its oval size moves similar air to a 10" woofer. Add a decent mono block amp that does 300-400 watts RMS into 2 ohms and an aftermarket head unit, and the factory sub's sound can be improved further. Most of the underseat type of self-powered subs will reproduce a portion of the bass spectrum (and will certainly produce some bass), but just don't have the throw to move enough air in a way that compares to a traditional sub.

I know it comes down to expectations, the money you are willing to pay, and the space you are able to devote to good sound. An inexpensive plug and play option is a win for the people chiming in here in your thread, but with a little work, careful equipment choice (i.e. choosing a good subwoofer that works with a small air space, and building an enclosure that is perfectly sized for it) and marginally more money, really good bass that surpasses the plug & play options can be achieved- that was my point. Not everyone wants or needs SQ quality bass in a daily driver, and many people value plug & play over performance. It really boils down to what sort of performance you are wanting and what you are willing to do/pay for it. I moderated an audio forum for years (same username) and have installed and played with many products in the last 35 years from mild to high end, and found more people displeased with underseat subs than happy.

You can make a removable box as small as .75 cubic feet for a decent middle of the road 10", bump that up to a cubic foot for a similar 12". There are some very capable 8" woofers that outperform the underseat type subs that will work in a half cubic foot. A decent entry level sub can be had for either side of $100 depending on what you want. There are some lower budget mono amps for similar price that don't suck (and many that do)...for budget amps, PPI/Soundstream has some that will do rated power near that price point. A sheet of MDF to build an enclosure isn't terribly expensive, and a sealed enclosure of the correct size that is removable won't take a ton of room. Building your enclosure to fit on the side of the cargo area like the Stealthbox is another option that will maximize cargo room and minimize footprint. Going this route will give you a better shot at realistic sounding bass, closer to what a good home system provides and doesn't have to cost a lot or draw attention.

^^ the Stealthbox is expensive for what it is, but for illustration purposes, that is where it mounts

If you can, demo the factory Alpine sub in a Jeep (again), and demo the products mentioned in this thread by other members. I have no intention of pooping on the opinion of other members, but do hate to see people spend money and get disappointed with the results. They aren't disappointed, but may have different expectations- find out what yours are and then choose accordingly.

 

I have the Kicker HS8 and I am very happy.

 

I am running subs under both front seats in enclosures designed and built by #mattk11 I am very please with the sound and output. They are powered by a Rockford Fosgate PBR300x1

 

Projected completed everyone. I appreciate everyone's feedback.

I installed the Cerwin Vega VPAS10 under my passenger side seat. Ran the power along the passenger side carpet/trim up into the right side of the glove box and through the foam firewall passthrough. Found a factory ground when I took out the passenger seat that I used. Ran the RCAs and Remote Turn On wire up the center console area. Not using the sub's wired remote as I use the head unit to control my subwoofer, however, it uses what looks like an RJ11 plug n play connection so if I feel like I need it later I'll add it. I had it briefly connected and found myself distracted by the bright blue LED on the remote.

First impressions: I'm impressed. Very impressed. This thing gets loud and thumps! Definitely worth the investment in my opinion. I can't believe how much I was missing out on. Has a nice solid steal body and weights between 10-15lbs. Fits great under the seat (recommend taking the seat out of the vehicle to make install easier). Total install time took about 1.5hrs...not bad. I've owned several different vehicles in my lifetime and it amazes me how freakin' accessible and easy Jeeps are to work with. It just doesn't get any easier!

Thanks again!

 

Did you screw the sub into the floor of the Jeep under the passenger seat? What size screw did you use? The ones that came with the sub or others? I just installed and am concerned about drilling into the gas tank

 

Kicker hideaway under drivers seat JKU.

Finally installed my kicker hideaway under the drivers seat (18'JKU). Plenty of room that I fab'd two brackets and placed under the drivers seat (off the floor incase of water). One thing to note, I ran with the sub on the floor for a few weeks before the bracket install, and have since noticed a difference in sound since the lifting. Likely due to the air volume. Was happy with the sub prior to the bracket install so much that I may go back to it. Brackets were $8 in aluminum from HD with a homemade brake (square tube and door hinge), plus velcro.

On a side note, was looking for a full bass to complement the trebles and midrange. This is a preference thing only. I spend the money via the frequencies (most on trebles, then midrange, finally bass). Had the alpine sub in the back for a while, but unless you need bass to be the focus of your music as opposed to a complement, it may not be worth the cargo space. The underseats are more than capable to fill the low frequencies and with the roof off, the sound is bled so much that it doesnt matter (to me for my listening preferences).

 

Finally installed my kicker hideaway under the drivers seat (18'JKU). Plenty of room that I fab'd two brackets and placed under the drivers seat (off the floor incase of water). One thing to note, I ran with the sub on the floor for a few weeks before the bracket install, and have since noticed a difference in sound since the lifting. Likely due to the air volume. Was happy with the sub prior to the bracket install so much that I may go back to it. Brackets were $8 in aluminum from HD with a homemade brake (square tube and door hinge), plus velcro.

On a side note, was looking for a full bass to complement the trebles and midrange. This is a preference thing only. I spend the money via the frequencies (most on trebles, then midrange, finally bass). Had the alpine sub in the back for a while, but unless you need bass to be the focus of your music as opposed to a complement, it may not be worth the cargo space. The underseats are more than capable to fill the low frequencies and with the roof off, the sound is bled so much that it doesnt matter (to me for my listening preferences).

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how did you end up securing the sub to the two brackets you made? I got an Alpine powered subwoofer but it doesn't have the brackets liken the jeep specific does. I need to make something up as its also down firing. I'm probably going to do exactly what you did to just be done with it.

Any measurements or anything you could give me or tips?

Thanks!

 

I can’t say for sure that it will fit under a Wrangler seat but I put one of these under the seat in my RV and it’s sounds fantastic. Can be bought with or without wiring kit.
NVX QBUS8v2 Under Seat Powered Subwoofer Enclosure + FREE Amp Kit