Prius Hidden Subwoofer

When I bought my Prius, I knew I needed to have space available for traveling with the family and such. But of course, shortly after I got it, I had to figure out how to get some better sound out of it. I decided to see what I could fit into the storage space between the hatch area and the spare tire. A slim sub and amp fit in here pretty nice and I'm happy with the results. It's not as good as a large box but it satisfies most of my needs.

And of course, when I put the cover down over it, it's hard to tell that anything is going on. To try to allow the sound out and keep the amp from overheating, I used a heavy wire shelf in the middle of the cover. Then put a layer of Modders Mesh over it to cover the large holes so that nothing can poke through. I used some silicon culk along all of the edges to make sure there's no rattle.

The box has 0.7 cu ft for the Pioneer TS-SW3001S4 12" slim subwoofer. The Q for the box is 1.05 which is higher than I prefer. It's a little lacking on the really low base. The amp mounts on the board on the right with room for the wires behind it.

One of the other options I wanted was to have the ability to remove the whole setup in case I need every last bit of space in the car. I installed a pair of male/female 8-wire connectors, one for the high-level in to the amp from the stock head unit and the other going to the speakers. I used a trailer light connector for the power and ground wires. When I remove the system, I can plug the male/female speaker connectors together and feed the front/rear speakers directly from the head unit.

The whole thing put together with a cover around the Alpine MRX-V70 5-channel amp to hide most of the wires. I've been meaning to pair or carpet the whole thing. But, it's hidden from view so there's little incentive to do so.

Here you can see the speaker in/out and power connectors. Plus I have handels on the sides to make it easier to handle when installing or removing.

And the wires all plugged in.

There are adapters for the front and rear speakers although I don't remember seeing much at the time I started this. So I made my own. I used 1/4" plywood for the base and then 1/2" MDF as a spacer. I'm showing some Infinity Kappa 62.9i here but those are now in the rear doors. The front has Infinity Kappa 60.0cs components with the woofers in the door and the tweeters in the dash.

I did a similar thing for the rear doors.

And made a mount for the tweeters in the dash. The larger tweeters fit well in the opening. Unfortunately the terminals on these suck and strip very easily. So I had to try to solder the wires directly to it which was also not easy.

The last mod I made was with the wiring for the head unit. I needed to route the speaker output to the amps. But instead of just splicing directly in, I used 8-pin computer power extension cables for the 8 wires I needed for the 4 channels. Cut it in half and spliced one half to the head unit speaker outputs and the other half to the actual speaker wires. Connecting these would put the system back to stock with the head unit driving the front/rear speakers directly. I then spliced another matching connector to the new wires I ran to the amps which is what I'm plugged into now.

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