My sub project (spare tire area)
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Joined: Mar 2007
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From: Los Angeles, CA
My sub project (spare tire area)
First, some background......
Like all other S2000 owners, I absolutely love my car, but hate the stereo is comes with. I upgraded the headunit and added the headrest speakers which were a huge improvement. However, there was still the one thing lacking....BASS!!
So I looked at my options.......Unfortunately, all options out there involved either A)spending alot of money, and/or B) losing valuable trunk space (most times, both!)
I like taking roadtrips and I like to golf every now and then so I did not want to give up any trunk space (so I ruled out all options of using the spare tool area). The custom boxes that go on the sides of the trunk are very cool, but again I didnt want to be taking them out everytime I wanted to hit the driving range or cruise to vegas).
The installations in the passenger footwell look cool, but I did not have the resources or cash to pull something like that off.
So, I went after the one place I knew I could definitely do without....the spare tire area!! I have AAA so I took out the spare a long time ago.
Here is a complete step by step process of what I did last week (I'll list materials and prices at the end)......
First off, anyone that has seen that area knows that its very tight, seems too small for any sub box to fit in there. You definitely want to make sure you have the right sized enclosure (otherwise your bass will sound like shit, no matter what amp or sub setup you have). That was one limitation. Another was that all I had to work with was a Dremel, and a handsaw (don't laugh). I wanted to mainly keep the cost of the project down so I wasn't about to buy special tools that I will hardly ever use.
Therefore, the only option was to make a simple sealed, rectangular cube box (no fancy angles or cutouts).
Knowing this, I measured the maximum dimensions that would fit in that area are: .45'(tall)x1.45'(wide)x1.42'(deep). Keep in mind that those are in feet, which is what my cheap tape measure had increments of (tenths of feet, not inches) so you can do the easy conversions if you want inches.
You always want to use 3/4"MDF board for speakers, so a new issue was having the box be deep enough for the sub to fit, and have enough room for the sub to expand without hitting anything when the music was booming.
I quickly realized that this couldn't work if the speaker was facing up (unless I wanted to install a 6.5 sub, forget that shit!). The cool thing I noticed about the spare area is that it isn't flat, it bends and gets shallower in the back left corner (facing from the back of the trunk), as you can see in the first pic above. This meant that I could build the box all the way to the top, and as long as the sub is within the deepest part of the spare area, it would "float" and have enough room to fully expand without hitting the bottom. This also means that the back edge of the box would have to sit on top of the rear sway bar.
Time to cut.....
(I wasn't kidding about the handsaw! Luckily, MDF isn't that tough to cut, but far from easy at the same time!)
First I cut the bottom to make sure that the footprint of the box is correct...
As you can see above, there is close to an inch of space behind the bar from the box to the bottom of the trunk.
Now that I knew the dimensions checked out, I cut the rest of the pieces and duct taped them together to check the entire fit...
I forgot to take a pic because I was so excited, but trust me, it fit perfectly but there was one thing in my way...
this corner piece of the bracket holding up the tray was hitting, and I had to cut it to get the box to fit flush (so that I could later make a flat panel to cover the entire spare area correctly.
Got out the dremel and took care of the issue...
Dont worry, its not a crucial cut, and the tray did not come crashing down.
So now that I had my box, I had to see what (good) subs were out there that could fit inside AND more importantly, be able to sound good in the small amount of airspace. By the way, using the dimensions I stated above, and using 3/4" MDF, the box gives you only .55 cubic feet.
Only having about 4.5inches of mounting depth, I had to go for a shallow mount sub. Unfortunately, there aren't many "good" ones out there, and I really wanted a 10" instead of an 8". Luckily, I found this badboy that was perfect.....
Only needs 4.25inches mounting depth, and .65 cu feet in the enclosure (yea, I am running alittle small with my box, but its close enough to use polyfill (box stuffing) to make up the difference. Plus, 300watts RMS was a good amount of power handling for that size sub.
Now that I had the sub, I needed juice. I found this small new Alpine monochannel amp was perfect.....
500watts RMS is a bit much, but since the sub had dual voicecoils, I would just wire it to 4ohms and I had the perfect combo, 300watts RMS to a 300watt sub.
I got them both brand new wholesale for 200bucks!!!!
Back to the box.....
Started putting the sides together with wood glue and screws....
Once you have the bottom and sides together, you have to now seal all the edges to have an airtight box (you dont want to wait til all the box is enclosed to seal cause I imagine it would be a pain to get all the edges at once)
Now its time to cut the hole for the speaker. I looked at the specs for the sub to make sure the hole I was cutting was the right size (not all 10" subs have the same cutout area).
if you have balls, you can trace the circle freehand. I took no chances and used an old school geometry compass to get a perfect circle. Notice the location of the cutout is towards the edge, this is that area right behind the bar that has enough room for the sub to expand. Also notice that I used wood glue on the outside to REALLY make sure the box was fully sealed. Didnt want to find out there was a leak after the box was finished.
Its Dremeltime.....
I recommend using a jigsaw if you have one. I dont think the Dremel was made to cut 3/4"MDF, took forever and I think I was close to breaking it a couple times. But it did the job. I made sure to cut inside the line, cause I could always use the sander to widen it later. (no, I didnt cut an entire inch inside the line! The outside line you see is the perimeter of the entire speaker.
this step might be alittle redundant. I initially used wood glue to seal the inside edges, but then I followed up by also using a latex sealant on top. Again, didnt want to risk a leak.
Went back to the car to check the fit.....
Looking good!!!
Finally, I attached the top piece and sealed it like the other sides....
From an old sub project years ago, I had an extra set of speaker terminals that I cut the circle for (using the dremel) and attached. Apparently I was too excited to take a picture of this step, but you'll see them later...
I went to a local car upholstery shop and the owner was nice enough to give me some scrap plastic paneling (for later) and some scrap carpet for free!! Using a spray adhesive and a razor blade, I cut the carpet to cover all sides.
(you can see the terminals).
As mentioned before, I added polyfill (just gutted an old pillow and stuffed the inside of the box loosely) to make up for having an enclosure that is slightly too tight for the recommended airspace.
And finally, attached the sub....
Unfortunately, I didnt take a full picture of the completed sub box in place (dont know why, just forgot!!) but trust me, it fit perfectly (actually, alittle tight)! The good thing was that it was so snug that I didnt need to secure it down with anything, but its not going anywhere.
Here is a pic where you can see the room the sub has underneath...
more than enough space, there is no way the cone surround could hit the bottom.
Now that the sub is finished, time to make the trunk look professional. As I mentioned, I got some extra carpet and some plastic scrap from the upholstery place and I took a bunch of measurements (many were just trial and error) to get the template for the rear panel.....
Here are some shots of it in place......
notice that I cut off most of the left section as well (the part that bows in).
Using the scrap carpet piece, I trimmed and glued it to the plastic panel...
Finished!!! Notice that extra piece sticking out of the right side, you'll see why that was necessary at the end....
Making sure the holes lined up was a major pain in the ass!!! But I got it to work. The important step is you measure, measure, and measure again!!! I even missed a couple times, but the important thing is to get it right with the plastic piece before you attach the carpet (that way you can cover up any fckups and no one will know!)
Here is the finished product......
Notice on the right where I tucked in the wires underneath the extra piece of carpet (told you it would come in handy), but its still in front of the panel piece. I know I could've done a better job of hiding the wires, but I didnt want to put any holes in the panel in case I wanted to move the amp somewhere else in the trunk, didn't want a gapping hole showing.
Here is another shot. I screwed the amp onto the metal trunk panel (its not just attached to the plastic panel). This also helps hold the panel in place, but if I take off the amp, the piece is still secured.
By the way, the bass sounds great!!! Nice and tight. Its not gonna hit like a highpowered 12", but trust me, it can easily rumble the S!! If you want to enter competitions, go with something bigger and lose your trunk space. If you want hard hitting clean bass, this is the way to go!!
The best part is that I still have my full trunk!!!!
Here is a main cost breakdown:
Components:
Alpine MRP-M500 Amp - $130
Alpine SWS-1043D 10" Sub - $70
4-gauge amp cables - $20
LOVE WHOLESALE!!!!!
Materials:
2'x4' 3/4" MDF Board - $10
Wood Glue - $3
Wood Screws - $2
Latex sealant - $2
Carpet Scrap - $0
Plastic panel scrap - $0
Polyfill - $0
Total project cost = $237
Let me know if you have any questions, I mightve left out some stuff here and there. It took me about a week to finish. I work during the day so I could only do a couple hours every night. I couldve also cut the time down if I had better tools, but it shows you whats possible with a handsaw and Dremel!
-MO-
Like all other S2000 owners, I absolutely love my car, but hate the stereo is comes with. I upgraded the headunit and added the headrest speakers which were a huge improvement. However, there was still the one thing lacking....BASS!!
So I looked at my options.......Unfortunately, all options out there involved either A)spending alot of money, and/or B) losing valuable trunk space (most times, both!)
I like taking roadtrips and I like to golf every now and then so I did not want to give up any trunk space (so I ruled out all options of using the spare tool area). The custom boxes that go on the sides of the trunk are very cool, but again I didnt want to be taking them out everytime I wanted to hit the driving range or cruise to vegas).
The installations in the passenger footwell look cool, but I did not have the resources or cash to pull something like that off.
So, I went after the one place I knew I could definitely do without....the spare tire area!! I have AAA so I took out the spare a long time ago.
Here is a complete step by step process of what I did last week (I'll list materials and prices at the end)......
First off, anyone that has seen that area knows that its very tight, seems too small for any sub box to fit in there. You definitely want to make sure you have the right sized enclosure (otherwise your bass will sound like shit, no matter what amp or sub setup you have). That was one limitation. Another was that all I had to work with was a Dremel, and a handsaw (don't laugh). I wanted to mainly keep the cost of the project down so I wasn't about to buy special tools that I will hardly ever use.
Therefore, the only option was to make a simple sealed, rectangular cube box (no fancy angles or cutouts).
Knowing this, I measured the maximum dimensions that would fit in that area are: .45'(tall)x1.45'(wide)x1.42'(deep). Keep in mind that those are in feet, which is what my cheap tape measure had increments of (tenths of feet, not inches) so you can do the easy conversions if you want inches.
You always want to use 3/4"MDF board for speakers, so a new issue was having the box be deep enough for the sub to fit, and have enough room for the sub to expand without hitting anything when the music was booming.
I quickly realized that this couldn't work if the speaker was facing up (unless I wanted to install a 6.5 sub, forget that shit!). The cool thing I noticed about the spare area is that it isn't flat, it bends and gets shallower in the back left corner (facing from the back of the trunk), as you can see in the first pic above. This meant that I could build the box all the way to the top, and as long as the sub is within the deepest part of the spare area, it would "float" and have enough room to fully expand without hitting the bottom. This also means that the back edge of the box would have to sit on top of the rear sway bar.
Time to cut.....
(I wasn't kidding about the handsaw! Luckily, MDF isn't that tough to cut, but far from easy at the same time!)
First I cut the bottom to make sure that the footprint of the box is correct...
As you can see above, there is close to an inch of space behind the bar from the box to the bottom of the trunk.
Now that I knew the dimensions checked out, I cut the rest of the pieces and duct taped them together to check the entire fit...
I forgot to take a pic because I was so excited, but trust me, it fit perfectly but there was one thing in my way...
this corner piece of the bracket holding up the tray was hitting, and I had to cut it to get the box to fit flush (so that I could later make a flat panel to cover the entire spare area correctly.
Got out the dremel and took care of the issue...
Dont worry, its not a crucial cut, and the tray did not come crashing down.
So now that I had my box, I had to see what (good) subs were out there that could fit inside AND more importantly, be able to sound good in the small amount of airspace. By the way, using the dimensions I stated above, and using 3/4" MDF, the box gives you only .55 cubic feet.
Only having about 4.5inches of mounting depth, I had to go for a shallow mount sub. Unfortunately, there aren't many "good" ones out there, and I really wanted a 10" instead of an 8". Luckily, I found this badboy that was perfect.....
Only needs 4.25inches mounting depth, and .65 cu feet in the enclosure (yea, I am running alittle small with my box, but its close enough to use polyfill (box stuffing) to make up the difference. Plus, 300watts RMS was a good amount of power handling for that size sub.
Now that I had the sub, I needed juice. I found this small new Alpine monochannel amp was perfect.....
500watts RMS is a bit much, but since the sub had dual voicecoils, I would just wire it to 4ohms and I had the perfect combo, 300watts RMS to a 300watt sub.
I got them both brand new wholesale for 200bucks!!!!
Back to the box.....
Started putting the sides together with wood glue and screws....
Once you have the bottom and sides together, you have to now seal all the edges to have an airtight box (you dont want to wait til all the box is enclosed to seal cause I imagine it would be a pain to get all the edges at once)
Now its time to cut the hole for the speaker. I looked at the specs for the sub to make sure the hole I was cutting was the right size (not all 10" subs have the same cutout area).
if you have balls, you can trace the circle freehand. I took no chances and used an old school geometry compass to get a perfect circle. Notice the location of the cutout is towards the edge, this is that area right behind the bar that has enough room for the sub to expand. Also notice that I used wood glue on the outside to REALLY make sure the box was fully sealed. Didnt want to find out there was a leak after the box was finished.
Its Dremeltime.....
I recommend using a jigsaw if you have one. I dont think the Dremel was made to cut 3/4"MDF, took forever and I think I was close to breaking it a couple times. But it did the job. I made sure to cut inside the line, cause I could always use the sander to widen it later. (no, I didnt cut an entire inch inside the line! The outside line you see is the perimeter of the entire speaker.
this step might be alittle redundant. I initially used wood glue to seal the inside edges, but then I followed up by also using a latex sealant on top. Again, didnt want to risk a leak.
Went back to the car to check the fit.....
Looking good!!!
Finally, I attached the top piece and sealed it like the other sides....
From an old sub project years ago, I had an extra set of speaker terminals that I cut the circle for (using the dremel) and attached. Apparently I was too excited to take a picture of this step, but you'll see them later...
I went to a local car upholstery shop and the owner was nice enough to give me some scrap plastic paneling (for later) and some scrap carpet for free!! Using a spray adhesive and a razor blade, I cut the carpet to cover all sides.
(you can see the terminals).
As mentioned before, I added polyfill (just gutted an old pillow and stuffed the inside of the box loosely) to make up for having an enclosure that is slightly too tight for the recommended airspace.
And finally, attached the sub....
Unfortunately, I didnt take a full picture of the completed sub box in place (dont know why, just forgot!!) but trust me, it fit perfectly (actually, alittle tight)! The good thing was that it was so snug that I didnt need to secure it down with anything, but its not going anywhere.
Here is a pic where you can see the room the sub has underneath...
more than enough space, there is no way the cone surround could hit the bottom.
Now that the sub is finished, time to make the trunk look professional. As I mentioned, I got some extra carpet and some plastic scrap from the upholstery place and I took a bunch of measurements (many were just trial and error) to get the template for the rear panel.....
Here are some shots of it in place......
notice that I cut off most of the left section as well (the part that bows in).
Using the scrap carpet piece, I trimmed and glued it to the plastic panel...
Finished!!! Notice that extra piece sticking out of the right side, you'll see why that was necessary at the end....
Making sure the holes lined up was a major pain in the ass!!! But I got it to work. The important step is you measure, measure, and measure again!!! I even missed a couple times, but the important thing is to get it right with the plastic piece before you attach the carpet (that way you can cover up any fckups and no one will know!)
Here is the finished product......
Notice on the right where I tucked in the wires underneath the extra piece of carpet (told you it would come in handy), but its still in front of the panel piece. I know I could've done a better job of hiding the wires, but I didnt want to put any holes in the panel in case I wanted to move the amp somewhere else in the trunk, didn't want a gapping hole showing.
Here is another shot. I screwed the amp onto the metal trunk panel (its not just attached to the plastic panel). This also helps hold the panel in place, but if I take off the amp, the piece is still secured.
By the way, the bass sounds great!!! Nice and tight. Its not gonna hit like a highpowered 12", but trust me, it can easily rumble the S!! If you want to enter competitions, go with something bigger and lose your trunk space. If you want hard hitting clean bass, this is the way to go!!
The best part is that I still have my full trunk!!!!
Here is a main cost breakdown:
Components:
Alpine MRP-M500 Amp - $130
Alpine SWS-1043D 10" Sub - $70
4-gauge amp cables - $20
LOVE WHOLESALE!!!!!
Materials:
2'x4' 3/4" MDF Board - $10
Wood Glue - $3
Wood Screws - $2
Latex sealant - $2
Carpet Scrap - $0
Plastic panel scrap - $0
Polyfill - $0
Total project cost = $237
Let me know if you have any questions, I mightve left out some stuff here and there. It took me about a week to finish. I work during the day so I could only do a couple hours every night. I couldve also cut the time down if I had better tools, but it shows you whats possible with a handsaw and Dremel!
-MO-
Nice job!
I'm very impressed. I'm considering doing this myself. I've been ready to install a sub for the longest time. 
