Space-saving 8" sub build

[canonman]

Hi there, I've not posted on here for a long time, but it's been a handy source of info over the last couple of years so I thought I'd share my project in case anyone else was thinking of doing something similar.

At the moment I have a two channel amp in the bin behind the driver's seat and wanted to upgrade to a 4 channel amp and an 8" sub.  As I often use the slightly bigger bin behind the passenger seat, I really didn't want to have to lose that limited storage space so after a lot of brainstorming, I came up with the following plan to fit an 11 litre enclose for an 8" sub and 4 channel amp.

I've struggled to find any info on how such an odd-shaped enclosure will perform, but as far as I'm aware the shape of an enclosure isn't important,  only the volume.  I have no idea if this will work properly or not.  It may not be perfect, but it'll certainly get me a bit more bass.  

The sub is going to be the shallow mount pioneer 8"  Most 8" subs will fit, but with only a few millimetres to spare behind, I figured a shallow mount would be the best option.  

The amp is going to be the Alpine F640.  It's pretty much the only affordable option that will fit, especially taking into account the wires connecting to it on either side.


I started off with a half-arsed design and a quick cardboard mock-up just to check that it would fit ok.






Then stared building with 12mm MDF
















And a check to make sure it fits ok




I'll report back when it's all up and running   s:) s:)

[onion86]

Nice idea, I have doubts it will work thought but interesting to see if it does! I wouldn't really say it's 'space saving'  s:) s:)

[simers]

Nice idea, I have doubts it will work thought but interesting to see if it does! I wouldn't really say it's 'space saving'  s:) s:)

It should work depending on depth of the sub as in if its too close to base of enclosure the sound will be shocking

[stargazer30]

Always good to see a DIY effort on sub boxes.  I've tried various shapes and locations too.

The volume of the box looks large for an 8" driver though?  Also did you consider a UD sub from Nathan first?  Thats as space saving as it gets as it goes under the dashboard.

[nathanMR2]

Interesting build. Beginning to see a few different things lately. It's unlikely I'm going to be building any more boxes any time soon to be honest. They take up too much of my time for not much of a return in comparison.

Amer currently has a box of mine for sale. Well worth it for real space saving.

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[AckersMR2]

Interesting build. Beginning to see a few different things lately. It's likely I'm going to be building any more boxes any time soon to be honest. They take up too much of my time for not much of a return in comparison.

Amer currently has a box of mine for sale. Well worth it for real space saving.

 l viewtopic.php?f=37&t=41566 l

I take it that's a "not likely"  s:lol: :lol: s:lol:

[nathanMR2]

Opps fixed  s;) s;)

[canonman]

I did consider the under-dash idea but decided against it for a couple of reasons.  Cost, hassle of fitting it, hassle of running more wires from the back to the front, and the limited choices of 6" subs.  This one only cost me £12.50 to build and the sub I got used off eBay so it was a no-brainer really.  

Sub arrived today, ran a signal from the PC with an 80z low pass on it and it sounds awesome, much better than I hoped.  I doubt it's going to crack the windows or anything, but I'm after pure sound quality anyway, not volume.  I don't even plan on having it turned right up, I just need that little extra bottom end to round everything off.

So, just need to cover the box it and get it all fitted in.

RE: not being much of a space saver... true, not as much as an under-dash one, but seeing as the bin behind the driver's seat is already taken up with an amp the only space I've lost is above the raised bit in the middle of the two bins.  I've still got the deeper passenger one to put stuff in.

RE: volume... it's 11508 cubic cm which is 0.40 cubic feet.  Right on the recommended volume for the Pioneer TS-SW841D.  I don't know if the narrow passage (56mm) between the upper and lower sections will make it behave as though it's slightly smaller, but like I said, I don't need it to be perfect, I just need a little more bottom end.

[stargazer30]

One of things I found with the UD sub vs a bin mounted box is the UD sub actually works with the roof down!  Other boxes just die when the roof is lowered as theres no cabin to pressurise and the bass just bleeds away.   The UB box uses corner effect and because its under the dash the bass is pretty much as good with the roof down.  Cost was a concern for me too.  6" ebay sub £20, until I could get the JL 6" sub later.   Wiring is very easy, not a hassle at all.  Fitting the thing is a royal pain in the butt though   s:lol: :lol: s:lol:

[nathanMR2]

You get very used to that  s:lol: :lol: s:lol:

I can remove and install my box in about 15mins now   s:wink: :wink: s:wink:

[Anonymous]

Looking forward to seeing how this pans out...

Although it doesnt look too space saving to me.. I think underdash is more...

But like i said, i will be very interested to see how this looks and sounds - i like a project  s:D s:D

[canonman]

Here's the Pioneer 8" shallow sub...





Here it is in the box.  I had to remove the rubber gasket thing as it would have sat too tall and touched the back of the bin doors.





All fitted and it sounds mint!  Not overpowering but just enough bottom end to round the sound off nicely and also take some of the strain off the Focals!   s:bounce: :bounce: s:bounce:  

It's dark now but I'll get a picture tomorrow of it in the car.

[StuC]

Looks well finished. Interested in that installed piccy when you can  :-) :-) :-)

[AndyM]

Looks good!  s:) s:)

You might get some buzzing at certain frequencies (the rubber gasket helps remove it). If you do, an alternative could be some thinner foam cut to fit under the rim, just to give it a bit of padding between the box and the sub.

Being picky, I'm still not sure what the thin aperture in the middle would do to the SQ or response of the driver, I'd love to listen to it against a similar volume box to see if you can notice anything. The main thing with any audio though is that you like it, so by that measure it sounds like you've had a great success!  s:D s:D  

I'd love to see/hear it sometime at a meet or something.