Gen 1 R1T aftermarket subwoofer box install in gear tunnel

[TurboRusty]

Hey folks,
Sharing my journey of adding a solid aftermarket subwoofer and amplifier to the stock sound system.
I have a Gen 1 R1T, early VIN (sub 10k)

I started by copying a few other threads on the topic. example: https://www.rivianforums.com/forum/threads/simple-10-jl-subwoofer-install-in-r1t.26036/
Power wiring from battery, stock sub removal, amp turn on lead suggestion. All great.

I even got the same JBL sub/amp combo and wired it off the tapped audio from the stock sub. Then I hit a snag. Attempting to dial in the amp settings really seemed impossible. Either it was too quite or blew out super quick. After some digging I tested the audio signal to the stock sub, and it peaks in the 15hz range, which is quite strange, with a steep drop off in strength after that. The poor JBL, and most subwoofers in general, just don't have that sort of frequency range (I couldn't find documentation on the frequency range of this lil sub, so I'm assuming it's not great as is). Tested both the high level inputs and the low levels after a line out converter.

So next I tested the audio signal from the rear passenger door. Much better range of strong signal in the 25-45 range and a broader falloff from there. Using that signal was a night n' day difference. Ultimately I still wasn't thrilled with the JBLs output. Back to the drawing board.
(I sure missed my under seat storage as well)

I ended up getting a separate amp and upping the sub size to 12". I went with a brand I haven't used before, Hertz. Been running this setup for the last 3 months and I'm pretty happy with the results. Easily a 3x difference in subwoofer output over stock
LOC: LC2i
amp: Hertz 500w
sub: Hertz 12 inch low profile

I decided to build a subwoofer box to place in the gear tunnel. Trying to squeeze that 1 cubic feet of internal subwoofer box volume under the rear seat was going to be way more complicated than just making a square box that takes up >30% of the gear tunnel space.

And because I still love all the storage space under the rear seat and gear tunnel, I also choose to make this install easy to remove. Going camping? Just unplug two spots and I get all my storage space back.

I'm lazy and didn't carpet the box.
Amp and Loc attached to a quick disconnect plug sorta thing.

The amp and loc board still took up too much space, so I made a layered shelf that fits right where the stock subwoofer used to live.

and here's the box in the gear tunnel

Anyways, hope this helps anyone looking to take on a similar project. Feel free to ask any questions

Sponsored

 

[kroe]

Glad to see this tried, thought about putting the sub in gear tunnel when I did mine but ended up custom box that fits in stock location. If you want to hack the stock sub up you could bolt the top back in to hide the amp and make the interior portion look factory.

How much difference was it going from the under seat to the tunnel location? Any chance you tried the JL 10 in the tunnel to isolate the location difference from the larger sub?

 

[TurboRusty]

I didn't try the jbl in the tunnel and I didn't test the Hertz 12" under the rear seat.
I have been trying the Hertz in a few locations in the cab. On the floor right behind the driver seat was awesome and got a more direct body experience from the bass. Hertz sitting directly on the back seat wasn't amazing.
Having in the gear tunnel seems to give it some additional punch vs just sitting in the back seat.

 

[Revin]

So next I tested the audio signal from the rear passenger door. Much better range of strong signal in the 25-45 range and a broader falloff from there. Using that signal was a night n' day difference. Ultimately I still wasn't thrilled with the JBLs output. Back to the drawing board.

Nice find with the rear door signal! I have noticed that the stock sub signal is not that good. Where did you tap in for the rear speaker? Did you take off the whole door card and run a wire through the door? Or did you find the wire inside the truck?

 

[TurboRusty]

Nice find with the rear door signal! I have noticed that the stock sub signal is not that good. Where did you tap in for the rear speaker? Did you take off the whole door card and run a wire through the door? Or did you find the wire inside the truck?

My goal was to tap the wires at the passanger b pillar before they went into the door. I couldn't find any resources online on speaker wire colors, so I took off the panel of the door to see the colors of the wires going directly into the speaker. With that info I tapped them at the pillar and it worked no problem.
I only tapped one side and I think that's fine, and it's working well - so I didn't bother tapping additional signal from the driver side.

 

[Revin]

My goal was to tap the wires at the passanger b pillar before they went into the door. I couldn't find any resources online on speaker wire colors, so I took off the panel of the door to see the colors of the wires going directly into the speaker. With that info I tapped them at the pillar and it worked no problem.
I only tapped one side and I think that's fine, and it's working well - so I didn't bother tapping additional signal from the driver side.

Good idea. Can you share the wire colors you found? I’d like to do the same.

 

[TurboRusty]

Good idea. Can you share the wire colors you found? I’d like to do the same.

The door has two speakers (I think), both with a set of purple and black wires. I just picked one set, tested the signal with my multimeter and got good results.
Both sets of speaker wires look the same, so I recommend picking a set and testing them for signal and polarity. I'm assuming there is a different signal strength going to each speaker in the door.

A bit hard to tell, so look carefully

Pos = purple with black stripe
Neg = black with purple stripe

Sponsored