Subwoofer install in 1st gen Doublecab

Hi guys I just wanted to make a write up of my sub system I have installed into my 2001 Tacoma Double Cab PreRunner. It consists of two(2) SVC 4ohm Polk Audio MM840's in a SuperCrewSound.com box, hooked up to a Kenwood KAC-8105D wired in series for a 2ohm load. I love subs and good sound systems but when I bought this truck I wasn't thinking about what kind of radio I could put in it just that I liked the truck or not. I don't live in a bad neighbor hood just down the road from a club that dosen't have you higher standard guest, so a "please steal me" sub box on the back seat isn't what I wanted, I also didn't want to do too much cutting i.e. blow through boxes, and something not so hard on the wallet, fucking college is expensive!! So I started the search and found that 8's were about the biggest I could go.

To start I have 2 Polk Audio MM840's bought from Amazon.com for about $80 a peice. They sound great they will stay with just about any rap song you put on, but they really shine when you put on some Dubstep or some harder rock that has the double bass kick's, or anything that has very quick thumping high bpm bass to it. I am extremely happy with them and would buy them again in a heartbeat. They will shake the entire truck if turned up, and will shake the side-view mirrors with ease. By ear they drop off around 40 hertz and around 30 they just barely get muddy and distort.

The box was made by SuperCrewSound.com. It is a very high quality box and has some awesome customer service backing it, if you arent happy shoot them an email and they will respond very quickly to help you in whatever way they can. SuperCrew says that you have to remove the child restraint bar behind the rear seat to make them fit, I don't believe this to be true as I removed mine and then put in the box and you can see clearly where the bar used to be and the top of the box sit's slightly below the primer where it was. The jack holder you do have to remove, and the plastic peices on the back of the seat could stay if I had grills which I will also be ording soon.

My amp is a Kenwood KAC-8105D monoblock class D amp. I can run my subs hard all day long and this amp just won't quit and it never even thinks about getting hot. I have it wired in with 8 guage wire from the battery with a 30 amp fuse withing 6 inche of the battery. An 8 guage ground bolted to the bottom of the cab, primer/paint sanded off for metal to metal contact, as said its seeing a 2 ohm load so it's pushing the full 500 rms if I wanted it to. My gains are as follows: Input sensivity ~3/4 the way up. Frequency cutoff is at 150 hertz (120 on my Kenwood KDC-X395 head unit) and bass boost is at level 2 I believe it help with the lows that the subs struggle with.

Overall very happy with them they sound great paired with my dual Kicker DS65 in the front doors which I made a bracket so that they would fit. They overpower my kickers if turned up, but I will have them amped when I get the money.

A few pics:









Read Me: The MM840's that I've had in this box are great subs but in the interest of longevity of the box and subs I'd suggest you get something that will mount without a spacer or make and use a proper spacer out of wood, plastic, metal, something that won't wear out as easily as the rubber weather stripping. The weather stripping worked great for a while then the rubber got used to being compressed and leaked. The box finally had it today and just quit.

 

A few more that aren't in my gallery for some reason?

 

Thats cool!

 

Those Polks are fantastic speakers!! I have the 10" version(MM010) in a subXclosure and it sounds fantastic even though I'm not giving it nearly enough power! What kind of watts are going to those speakers?

 

would two 8s be louder and hit harder than one 10? (generally speaking)

somewhere there is a premade box for our doublecabs for one 10 behind rear seats.

nice install..how much was shipping on box?

 

i need to do this so bad. i lost one of my back seats to a sub box, this looks like a better option. nice work btw

 

I've got the full 500 rms ability to put to them but have the gains turned down so that I won't over power my mids and highs. I downloaded a tone generater onto my Ipod and went thru the frequencies adjusting the amp untill I went thru them all without the subs bottoming out or anything else like that

They are compareable to 1 JL Audio 10W3v3-4 on the same amp. My friend has two in a Ford F150 Doublecab Downfiring under the rear seat he unhooked one and we lined our trucks up and played the same song with other friends around and they couldn't tell much diffrence. I couldn't find a 10 inch box that would fit a decent 10 inch sub. And shipping was ~$30 cross country from Cali to my house in SC.

Thanks! And I would have lost the back seats but I'm always riding to Charleston with a truck full of friends so that was a no-go.

 

My 10" has a max wattage of 700 and rms max is 350. Are you running over the max recommended wattage, even with the gain turned down?

 

Each sub is 250 rms and like 700 max. So o have a 500 rms at 2 ohm amp with the subs wired to deliver a 2 ohm load. I'm running max RMS watts, but couldn't know for sure unless I put it on a multi meter.

 

It's possible that my amp could be stronger than advertised, I couldn't know unless I put a meter to it which I may do just to know what its truly putting out.

 

Yeah, I'm curious to see what each sub is getting. I don't want to go over the maximum recommended wattage but, if you're giving that much power and they're taking it just fine then maybe I'd put some more thought into getting a bigger amp.

 

I'm happy with them. They are getting max rms so there's no point in going over that because I'd like them to last a little while.

 

Are the subs over obnoxious? or do they actually sound pretty good?
I also noticed the box says mounting depth of 4 inches but the polks are 4 1/8, are they hitting on the back of the box?

 

They sound good. They hit hard when I want them too and will blend with my un-amped door speakers when I turn them down. If you notice the white stuff between the box and subs it's a piece of weather stripping I used as a spacer for them. They sit in the box fine with it on there just a little tight. I don't have a grill guard on them but I can't hear them hitting the seat and the parts of the seat the stick out the most are right in the middle of the sub so I can't see anything hitting.

 

I decided to run my subs through a box software just to do it and this is what I got, it's about what I was expecting and is a nice smooth curve but drops off really early which is why I'm going to be building another box soon as I get the money and put 2 10's in it. I did it also to help describe how they preform if I decide to sell them soon. As you can see they start dropping off right around 60 hertz which isn't horrible but still not great as that means that it can't handle a lot of really bass heavy rap music but they still sound great to me and when I get to thinking about selling them I just can't quite bring myself to do it. I may sell them when I start/finish my system redo but who knows I may keep them there in case I take some friends with me and decide that I don't want the box back there.

 

Can you tell me the dimensions of your box? I'm thinking about making one myself. And also when you said you thought 8" inch was about as big as you could go what did you mean? Thanks

 

guys, none of your numbers actually mean anything. get an SPL meter and measure

wattage means nothing without knowing woofer efficiency, cabin gain, input signal strength, input voltage and amperage.......

diesel trucks can make 1000hp, doesn't mean they are fast.