Under Seat Subwoofer Club (USSC)

Ahhh, good to know the latch movement works. And the post on the first page is actually of two 8" subs. I changed what subs I'm using but still rocking the same setup back there!

 

here is my setup from about 4 years ago it has been moved over to my 2016 when i got it and need to redo the molded fiberglass back so it fits a bit tighter; the new truck has a slightly different pattern on the back wall. i've been kinda lazy with it since i haven't carpeted it or anything but you can't see it behind the seat so who cares... i'm currently running the subs at 1000 wrms at 1 ohm and it sounds pretty good for the most part. when i do the remold on the back i may seal the box or redo the port not sure yet... the box is a bit too small for the subs suggested port volume so it doesn't hit right at all frequencies. i may also separate the subs and run each of them off of the 5th channel on my 2 5 channels for the front and back speakers. but having 1 kid and another on the way makes me feel like i should be an adult and remove the system to make more room in the truck.

 

I keep coming back here and to OP’s link to his origina build and subsequent endeavors. Been really toying around with joining the USSC and doing 2 JL W7 8’s underneath the rear seats.

Has anyone use the W7’s here before?

 

I think a w7 might be too deep, you need 7 inches of depth for that sub, not to mention the height of the surround and excursion may hit the bottom of the seat. I would go with some 6w3s or 8w3s.

 

I was thinking there’s more depth underneath. I’m liking the v3 of OP’s setup with line-x and looking into something similar to that. The W3’s I was never impressed with even back 15+ years ago when I actually knew a little about car audio. I’ve been out of it all for so long it’s not even funny...

Maybe I’ll look around and just see what’s out there these days, I just always remember the W7 was the king dingaling and when I googled it, it still appears to be.

 

I was never impressed with JL, but my experience with them was back from 2000-2004

But, look at these pictures in this post
https://www.tacomaworld.com/threads/tacoma-audio-endeavor.66365/page-3#post-1690542
There is a good picture that shows how much space there is between the subwoofer and the bottom of the seat.
He is using a 6 inch subwoofer, so imagine the w7 surround is going to be 1 inch on either side further out, and closer to the seat bottom.

 

It depends on what all you do to the "sub opening" under the seats. I cut out some rings of wood that raised the magnets of the subs off the floor. Those rings cutout perfectly (after some sanding) and gave me about an inch of clearance. I should get an inch and a half once I place a rubber ring around the wood ring as well.... It's doable, but your JL's are probably much taller than my MTX 10'S.....

 

W3s barely fit, check out my build for max clearance using fiberglass. No way a w7 will fit under there.
https://www.tacomaworld.com/threads/under-seat-sub-box-build.550333/

 

To get a W7 to fit under there you'd need to cut the sheet metal that forms the floor of the truck and weld in a sort of "bucket" to provide clearance for the magnets.
Not impossible, but likely a waste of time. Plenty of options that fit.

 

In the mid 1990's I installed a 10" sub in my standard cab 1988 Toyota pickup. ZERO interior room was lost. I built a band pass box for a Sounstream 10" woofer and mounted the box under the driver's side of the pickup bed and plumbed the port into the bottom of the cab in the center very close to the back wall. I then built a console to cover the port to keep crap from falling into the port and to make the sound bounce around the cab more for better frequency production inside the cab. I carpeted the entire box and then dumped a shit ton of fiberglass resin onto the carpet to make an incredibly hard shell that was waterproof. That woofer box suffered a lot of hits off roading but never showed any damage. The exhaust had to be slightly rerouted around the woofer box. The sound was amazing and I didn't lose ANY useable space anywhere and my seat still went all if the way back. Victory, lol. The only drawback is that the woofer was completely unserviceable and if it had ever failed the woofer and box would have had to been thrown away. Solder stops wires from falling off inside the box, lol.

 

I'm looking to install a set of 4 6.5-7 inch subs under the rear seat of my 13 double cab.

I previously ran a powered 10 inch sitting under the passenger seat which sounds fine for certain songs but hollow and tinny for others.

My question is what amp should I use to adequately power the subs? I plan on having it in the same location as the previous box to lessen the cable runs needed.

 

Power required will depend on the specific subwoofers you use.

 

Four of these

Massive Audio SUMMO64 – 6.5" Car Audio 300 Watt SUMMO Series Competition Subwoofer, Single 4 Ohm, 1.5" Voice Coil. Sold Individually

https://www.amazon.com/gp/product/B00K6SVSAC/ref=ox_sc_act_title_2?smid=A3TATDGCZS5A1K&psc=1

4 ohm, 150w rms, 300w max. I'd like each one on a different channel.

 

Any reason why you want each one on its own channel?
You will need to have a chamber for each sub if you have each on its own channel. If one channel is making bass, but the others are not, then only one sub will be going, it will just vibrate the other 3.
If you had the subs in 4 different places, then each on their own channel makes sense, but since they will all be under the seat they should all play at the same time.

You should wire them in series/parallel so they present a single 4 ohm load to either a mono amp, or a bridged 2 channel amp.

Also, 150x4 amps are not terribly common, and are generally designed for inside speakers. Your looking at spending near $1000 for a 4 channel that can do that, or $500 for a mono than can do the same.

 

Not true. There are amps that have signal aggregation switches that basically take the incoming signal and pipe it to all channels driven. You wouldn't need to segment the box. And there are plenty of powerful 4 channel amps.

That being said, I agree, putting each sub on its own channel is a complete waste of time and REALLY limits how many amps you'll have to select from.

A solid 600watt RMS amp that makes that power at 4 ohms is your best bet. Wire the subs in series parallel. Meaning, take subs 1 and 2 and put them in series. Then take subs 3 and 4 and put them in a different series set. Then parallel the two sets. this will yield a 4ohm load.

 

I was looking at crutchfields site since thats where most people would end up shopping, they had 3 amps that could do 150+ x4 and all were twice the cost of a similar mono amp.

 

I believe I understand what you are saying. I'll look for an mono amp in the 700+ RMS range.

 

Selling the tacoma, sub box must go! Looking for $600 and local pickup only (Carlsbad, CA)

https://www.tacomaworld.com/threads/under-seat-sub-box-build.550333/

 

I'd buy this in a heartbeat if i lived in CA...such a great piece of work!

 

Solid build. That's a LOT of extra work to make it removable but it's time well spent. Mine is literally part of the truck now.

Speaking of....I recently updated mine. The old subs were toast so I did something I should have done 11 years ago when I first built this box. I installed some Alpine Type-R 8s. I didn't want to at first because the Type are was a super hyped sub at the time but honestly, it's the perfect sub for that space and enclosure volume. They are dead flat to 20hz and it's kinda absurd. Best part? They even make a steel grill that installs as part of the mounting flange so there's zero chance of anything ever hitting the cone ever again. I'd highly recommend them.