under-seat powered subwoofer

Has anyone fit a compact powered subwoofer under the passenger seat or rear bench in a wagon? My interior is out of the car right now so it's a bit hard to tell how much space I have in the rear, but it looks like if I get *really* clever, I might be able to fit one under the passenger seat.


I was looking at the kenwood ksc-sw11: https://www.crutchfield.com/S-L4C7pS2BeJZ/p_113KSCSW11/Kenwood-KSC-SW11.html


The dimensions are 11 x 7.5 x 2.75 inches. I'm looking at the underside of the passenger seat and it looks like with the lateral beam and the lever adjuster, the only spot available is on the back side of the seat. The problems I'm seeing are that when someone sits in the seat, the foam intrudes on the little available space. The other problem is that the rear footwell heater will be heating my sub.


What I'm thinking about doing is building a sheet metal mount which will bolt in between the seat and the rails and mount the sub to it. My idea was to mount the sub upside down so that the top can be a solid plate. This way, I can limit the intrusion of the foam seat; as the person will eventually be sitting on foam sitting on aluminum. Then I can make some sort of deflector to make sure I'm not heating my sub.

I had planned to put my amp under the seat as well, but wound up with it under the floor in the way back as it wouldn't fit.

Nice and clean! Bet it is great to cruise in.

There was a recent thread on this topic and I can't find it!

Someone suggested a Bass Shaker which seems to me to be a great solution.

https://www.madisoundspeakerstore.com/bass-shakers/aurasound-ast-2b-4-pro-bass-shaker-each/

Yeah I think I remember seeing that thread. I remember finding out about the bass shaker recently. I don't think the bass shaker will actually produce much of a clean sound. More like rattle stuff.

Recycle the junkpile from the C70 fancy 11-speaker stereo?

It's got a quarter panel mounted trunk amp on a giant bracket in good quality?

IDK, I'm not that much into stereos. Maybe you can make a sub box that fits inside the spare tire rim but still keeps dirt out?
Use the rubber tire as dampening on the wagoon to keep it from rattling the body, but give you a decent round cone to give it a sub if you're into that without sacrificing any cargo space/having to hack & maim your interior too much? Use rim center-bore as port for ported box?

Flame away/burn me at the stake folks!

Someone could totally make this plug in/recombine the 90s OE volvo/Alpine k@@l-@id junkpile without sacrificing any cargo space/buying any new chinesium/supporting the corporation/nothing to seee or steal?

I did a search for c70 subwoofer and found a pretty big 10 inch subwoofer. I'm trying to avoid adding a sub that big although it is cool that it's a nice oem dynaudio unit. Then I have to add an amp too... I'm definitely trying to utilize the oem alpine amp that came with the car. If I find that it's lacking in power in some way, I have the 100W alpine amp from my v70 sitting in a box and I know that one isn't lacking in power :^)

V70R has the Dynaudio stuff & SC901 w/ '250W' amp under the passenger seat.
Not bad for the day/good enough for books on tape/the news?

Hate crowds, but live band on a stage studio is still never going to be comparable to the car.

Some nostalgia-trap there, that was a crackprice option new, good OE factory/warranty quality & what was cool when younger and now it's all (inflation adjusted) pennies on the dollar compared to new price/given you can get stereo stuff from wal-mart for like $30 for a head unit that has bluetooth/aux in holding the price on it way down as well as new cars that practically come with a home entertainment system built in/plenty good for avg joe making all your period OE quality/made in Japan & Europe Alpine/Boston/Dynaudio kool-aid worthless.

Paradoxically, a heathkit or marantz home amp or console can be crackprice depending what you have now for nostalgia reasons as much as anything...

So yeah, I'll stick to my guns, make it bolt to the hub of the spare wheel/tire flipped around or whatever for the sub.
Hang the amp somewhere in the other quarter by the fuel filler tube carefully behind the wheel well there?

I've got about 100' of wiring in the car now:

Head unit in front of car, to amp in back of car, back to speakers in front of car...

aharres said:

Yeah I think I remember seeing that thread. I remember finding out about the bass shaker recently. I don't think the bass shaker will actually produce much of a clean sound. More like rattle stuff.

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That was this one. http://forums.turbobricks.com/showthread.php?t=356717

Sure, I didn't think rattling the seat would be sonically pleasing, either. But it's absolutely amazing. My semi-educated guess is that the shaker gives the fundamental and possibly the 2nd harmonic (depending on the note of interest), while the mains give everything above. It's the "everything above" that causes our ears to perceive timbre or color. Nothing we listen to is a pure sine wave. The "everything above" is how we can tell that an instrument is, in fact, an upright bass, even if it's coming through 1" speakers on a laptop.

Put another way, does the lowest C of a pipe organ come out clean on any speaker? Even with an 18" sub? Getting bass notes you can feel is a chain reaction: the cone creates significant air pressure, which strikes the furnishings in the room, which you then feel in your seat. Once I discovered that the intermediate stage could be bypassed, it opened entire worlds of possibility.

If you want a vibrator, call Hitachi.
If you want a sub, call JL Audio

If you want a sub dont call overpriced jl audio

I just ordered a kenwood ksc-sw11. We'll see how I can get this thing to fit. It's the smallest power sub I could find. Seems like it'll have just enough power. Actually I should be able to use the factory heated seat wiring to power this thing. It's only 75 watts rms

aharres said:

I just ordered a kenwood ksc-sw11. We'll see how I can get this thing to fit. It's the smallest power sub I could find. Seems like it'll have just enough power. Actually I should be able to use the factory heated seat wiring to power this thing. It's only 75 watts rms

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I added that exact sub to my 740 under the drivers seat. It sticks out a bit, and folks sitting in the backseat have to be a little careful, but it fits well enough. It adds plenty to the overall quality of audio in the car as well.

Alright! Good to know you had a good experience with it. I can't wait to build my system. It'll be my first time doing this, but I think I'm going to have something that sounds really good.

aharres said:

I just ordered a kenwood ksc-sw11. We'll see how I can get this thing to fit. It's the smallest power sub I could find. Seems like it'll have just enough power. Actually I should be able to use the factory heated seat wiring to power this thing. It's only 75 watts rms

Click to expand...

I wouldn?t power anything off the factory wiring. Please run an actual power wire.

onelow89s10 said:

I wouldn’t power anything off the factory wiring. Please run an actual power wire.

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Yeah I was looking at the wiring diagrams and that circuit will only get power with ignition in run/start. I couldn't find any writing on the wires which would indicate gauge, nor did I see anything about wire gauge in the wiring diagrams. However, volvo decided to protect the circuit with a 16A fuse whereas kenwood has selected a 10A fuse. This seems to indicate that the heated seat wiring is physically capable of handling the load. The trick would be moving the spade terminal on the fuse block to a spot which receives power with igition in acc/run (and also won't be overloading an existing circuit) and then building a looped connector to bypass the missing heated seat switch.