1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

DIY custom subwoofer install

Discussion in '80-Series Tech' started by Hayes, Jul 27, 2005.

  1. Hayes

    Hayes

    Messages:
    2,348
    Media:
    8
    Albums:
    1
    Likes Received:
    568
    Joined:
    May 7, 2005
    Location:
    South Jordan, UT
    A couple years ago I had a local audio shop install Focal Access 6" separates in my front doors along with a 4 channel Viper amp behind the ps rear interior panel (where the factory "sub" was). I've also got some decent 6" Kicker coaxial speakers in the rear doors, and an OK Panasonic deck.
    After the amp and Focals were installed, the sound was awesome. Loud, clean and very musical. The bass was a lacking, but it sounded great nonetheless.

    The other day I got a wild hair to add a subwoofer.

    My goals:

    1. Add a sub and amplifier to fill out the bottom end. I don't listen to rap or music that demands monstrous bass, but I really wanted to fill in where the excellent Focals left off.

    2. I didn't want to lose ANY cargo space. None.

    3. I didn't have much $$. I had to do it all myself.

    Results:

    I did some research online, learned a bit about subwoofers and enclosures, downloaded a free enclosure design program, and started looking at different drivers.

    I estimated that I would be able to get about 1/3 of a cubic foot of airspace for a subwoofer enclosure behind the ps rear panel, next to my 4 channel amp--where the little cubby hatch is. I also figured I could mount a small mono amp somewhere behind the ds rear interior panel.

    I settled on the following equipment:

    One JL 8 inch 8W3 driver $100
    One JL e1200 200W (into 2 ohms) mono amp $175

    After the cables and tax I spent $300 at Car Concepts in SLC.

    I decided to add some sound dampening to all the doors and the rear body panels while I was at it. I spent $80 on 50 square feet of Fatmat. This is a helluva lot cheaper than Dynamat, and I figure it's almost as good.

    I also bought a sheet of 1/2 inch mdf, some heavy duty Liquid Nails, assorted screws, fiberglass batting, some metal strapping, velcro, adhesive foam tape, and other miscellaneous stuff from Home Depot.

    This was my first ever attempt at any custom car stereo installation short of putting in a new deck. It went well, with lots of tweaking, adjusting, and a little cussing.

    The enclosure went in easier than expected. I applied strips of foam tape to any area that could possible come into contact between the enclosure and the truck, and secured the enclosure with three metal straps.

    Here's a picture of the sub enclosure and the 4 channel amp that runs the doors. The enclosure is not pretty, but it is sturdy and well-sealed. The random placement of velcro is part of how I decided to finish it all off with the interior panel. I'll explain momentarily.

    [​IMG]

    [​IMG]

    I installed the amp behind the ds rear jack access panel. I obviously had to remove the jack as well as one of the jack's mounting brackets. No big deal to me, the jack now resides in my tool box. This turned out to be a great location because it is ventilated and I can easily access the amp to make adjustments.
    The amp is mounted to a piece of mdf, and the mdf is mounted to the truck with metal straps. The foam around the top of the amp is (temporary) extra insurance against a leaky window seal that I'm still fixing.

    [​IMG]

    The access door fits over the amp perfectly.

    I modified the the ps interior panel by cutting out the plastic cubby and trimming the panel to fit around the driver. I cut the cubby door to fit around the driver as well. I used a bunch of heavy duty velcro to attach the (now two pieces) cubby door and to sturdy-up the panel's attachments. I also added strips of Fatmat to the insides of both rear interior panels because I had plenty.

    The final result is sturdy, rattle-free, and looks better than I expected:

    [​IMG]

    [​IMG]

    After several days of tweaking levels and crossovers, the sound in my truck just plain kicks ass. The little 8 inch woofer puts out more bass than it has any right to, and it really fleshed out the bass notes and kick drums.

    I didn't lose any cargo space, the finished product is robust and sturdy, and it sounds great.
    I spent less than $400 and a lot of time, and I'm very hapy with the results.

    Hayes
     
    Last edited: Feb 27, 2006
  2. 2badfjs

    2badfjs

    Messages:
    5,522
    Likes Received:
    3
    Joined:
    Jan 26, 2005
    Location:
    in the garage
    awsome job! great write up too!!!!! :D
    you wanna come redo my 60's system? ;)
     
  3. Cobra Jet

    Cobra Jet

    Messages:
    123
    Likes Received:
    0
    Joined:
    Jul 11, 2005
    Location:
    Southern NJ
    Great install.

    The only thing I would do different would be to mount a cooling fan (can be purchased at Radio Shack) behind the panel where the amp is located. You want the cooling fan to blow fresh air across the amp's heatsinks.

    The reason I say this is, the amp is now almost "sealed" inside of that interior panel, and the excessive foam you have put around it will not allow the amp's heatsinks to cool or breather properly, it's actually suffocating it. Even though it may not look like the amp is being suffocated, there really is not a lot of breathing room behind the panel, especially with the insulation now there and the fact that the amp will get very warm when on. By installing a small PC-like cooling fan, this will push air across the amp's heatsinks and effectively cool it so it will not have a chance to overheat.

    The cooling fans are about 3" or less in size and are really quiet too, so there will not be any noticeable noise coming from the fan itself.

    This can be accomplished VERY EASILY:

    1) black wire on fan will get grouded to your ground wire (or chassis)
    2) red (hot or +) wire on fan gets tapped into the amp's turn on lead.

    Once you have the fan hooked up in that manner, when you turn on the head unit up front, the amp will turn on AND the cooling fan will also turn on at the same time. The cooling fan will stay on as long as the amp (or head unit) is "on". When you turn off the head unit, the amp & fan should power off.

    :)

    It will work flawlessly and it DOES work and help to cool the amp.

    I installed and have (2) small cooling fans cooling a PPI 5440 amp in my Cobra. One fan extracts hot air from the amp, while the other pushes fresh air into the amp over the circuit board. You can't even see the cooling fans either, nor can they be heard while the system is on. They can only be heard if there is no volume and the car is not running. Luckily the PPI amp's bottom cover was perforated in such a way that I was able to custom mount the fans in that manner noted above. I had the same exact setup in my prior 95 BMW M3. The amp has NEVER shut down or overheated, no matter how loud I had the system, or how hot the amp location was on a hot summer day.

    :beer:


    Nice job!!
     
  4. Hayes

    Hayes

    Messages:
    2,348
    Media:
    8
    Albums:
    1
    Likes Received:
    568
    Joined:
    May 7, 2005
    Location:
    South Jordan, UT
    Good idea with the PC fans, Cobra Jet.

    Like my (rather lengthy) write-up said, the foam is there to absorb any moisture that might sneak through my leaky window. Occasionally, a few drops of water sneak through the seal and sometimes drip down into the area after a carwash. I've done some things to seal it, but I haven't tested it out yet. I'll remove the foam as soon as I'm sure that I've solved the problem. Don't want to risk getting the amp wet in the meantime.

    The removable panel that covers the amp is vented, so the amp gets some air from the cab. I've also been running the amp in 100+ degree weather around here, and the thermal protection circuit has not activated.

    Your fan idea would be really easy to use, however. I think I will look at adding a small PC fan above the amp (where the foam is now) to pull air through the vents and accross the amp.
    Thanks.

    Hayes
     
  5. Cobra Jet

    Cobra Jet

    Messages:
    123
    Likes Received:
    0
    Joined:
    Jul 11, 2005
    Location:
    Southern NJ
    Hey Hayes - not a problem!

    Your idea above for your application will work perfectly as well! Best of luck, everything looks great!

    BTW - what head unit are you running?
     
  6. livelarg

    livelarg

    Messages:
    315
    Media:
    22
    Albums:
    1
    Likes Received:
    27
    Joined:
    May 11, 2005
    Location:
    OKLAHOMA cITY
    Looks great, I am wanting to make a box for both my trucks. You give me reason to get off my @ss.
     
  7. Hayes

    Hayes

    Messages:
    2,348
    Media:
    8
    Albums:
    1
    Likes Received:
    568
    Joined:
    May 7, 2005
    Location:
    South Jordan, UT
    Cobra Jet,
    I've got a somewhat cheezy Pansonic unit. It's got all the pre-outs, including one for the sub, but I've been told that my system would really benefit from a higher output voltage.

    A new deck is definitely a ways down the list of approved purchases (got in a little trouble with the subwoofer), but do you have any recommendations?

    Hayes
     
  8. Cobra Jet

    Cobra Jet

    Messages:
    123
    Likes Received:
    0
    Joined:
    Jul 11, 2005
    Location:
    Southern NJ

    Well, if you like "old school" head units, here's some I've owned:

    Alpine 7949 - awesome head unit and was a top of the line head unit it it's day. Even today there are few headunits that really compare to it. It had no internal amp, so you had to run an external amp. This kept the unit cool since there was no internal amp. It also had a copper cage, unlike many headunits today that come with just aluminized cages. It had MANY features on it, too many for me to type though. It was detachable face, had a remote and the front of the unit flipped down (not motorized) to reveal the CD slot behind it. Very clean face, not too cluttered. The unit sounds awesome due to no internal amp or noise... a great unit to own even today. This unit was used in MANY high end stereo competitions and received MANY high rated reviews by many Car Stereo Enthusiasts and Car Stereo Magazines, websites, etc... When new, these units retailed in excess of $700+... They now sell on eBay for about $150-$200, depending on condition and if the original box & other paperwork are included. For an old school Alpine, it's an awesome head unit that was way before it's time when comaring the feautres to comparable units available today.

    My current head unit is a Nakamichi CD400 (I'm pretty sure that's the model #). It's a very nice head unit, very clean front, no clutter at all - looks "business like" and is another great head unit. Looks awesome in nearly any vehicle because it's low key being all black (no bling to make it stand out screaming "steal me"). However, for the price of these units, they are fragile... I paid $400 for it, and the damn CD mechanism busted about a year ago... I still have the unit installed, it works excellent, sound excellent, but I can't play any CD's. So, I purchased an iPod and have the iPod hooked up to it to solve the broken CD issue... :) There is another Nakamichi head unit that is nice - and is more sought after, due to it being a better made unit. That one is the CD45z. This was the head unit produced before the CD400... The CD400 was actually modeled after the CD45z, so they look very similar except for minor changes in the face & features. You can pick up CD45z's for about $150-$200 - while the CD400 still is upwards of $250 or better... if I were to buy another Nakamichi, I'd go for the CD45z.

    There is a JVC KD-SH77 head unit in the Cruiser. Again, another nice head unit and was rated very highly by many Car Audio magazines. These too sell for about $150+ on eBay. It's an older model (couple years old, maybe), but again, it has MANY features suitable for a daily driver or one who has installed nice aftermarket components. it's very nice looking, still kinda "plain" on the face, but only comes in silver. It stands out once installed due to being silver instead of black - not too bad, but I'm one who would rather have "plain" over "bling"... Again, detachable face, CD behind face, tons of features and sound quality is awesome.

    I've had Sony head units in the past - had nothing but issues and will never buy another Sony head unit.... I've also had Pioneer and Kenwood... I'll go with kenwood over Pioneer just for the asthetics, as to me, the Kenwood looks better in design. Pioneer and Kenwood, for the most part seem to offer very similar options and pricing. Eclipse made some decent head units years ago, but now, I just don't like their designs plus their displays are very hard to see during the day light.

    You can research any of the above mentioned units by doing a search on Google using the name or model number and you'll see pictures of the units and find all of the features listed for each.

    :grinpimp:
     
  9. TX_TLC

    TX_TLC

    Messages:
    1,475
    Likes Received:
    8
    Joined:
    Apr 29, 2003
    Location:
    Texas
    Very nice write up and great pictures. Thinking out of the box with the sub placement.

    I am wanting to remove the stock "sub" and build something similar.

    On mounting the amp...you said you used metal straps...did you then screw these into the body?

    I don't remember the metal being too thick and puncture the outer skin. Can you expound on the amp securing.

    Thanks!
     
  10. lx450landcruiser

    lx450landcruiser Moderator

    Messages:
    2,779
    Likes Received:
    7
    Joined:
    Sep 22, 2003
    Location:
    Uganda
    it seems odd to me that you mounted the sub in on the left and the amp on the right where the old sub was. why cut a new hole when you could simply enlarge the stock home and look a little more factory? not baggen on ya just a little confused? i have had that pannel off alot and it seems youd have more room for the enclosure I.E more volume.
     
  11. Hayes

    Hayes

    Messages:
    2,348
    Media:
    8
    Albums:
    1
    Likes Received:
    568
    Joined:
    May 7, 2005
    Location:
    South Jordan, UT
    Why is the speaker to the left of the amp?
    Good question.
    TX_TLC has the answer. The amp was installed first. But now that you mention it, I cant think of a reason why I couldn't have moved the amp to the left and built the sub into the old sub location.
    I think it is good to have the old grill and the slots to vent the amp, but you could easily build some kind of vent into the cubby door.
    Yeah.
    The more that I think about it, I should have done it that way.
    Oh well. Such is the work of a rookie.

    Hayes
     
  12. Hayes

    Hayes

    Messages:
    2,348
    Media:
    8
    Albums:
    1
    Likes Received:
    568
    Joined:
    May 7, 2005
    Location:
    South Jordan, UT
    TX-TLC,
    You can see in the pictures that the amps and subs are mounted to the truck with metal straps. I screwed the straps into the sheet metal (using SHORT self-tapping sheet metal screws), but only in hidden, interior tabs and braces. There's actually alot of sheet metal to work with back there.

    On a related note, the shop that originally installed the 4 channel amp (the one next to the sub) screwed one of their mounting straps into the wheel well. The geniuses also left a couple little holes in the wheel well that let water through into interior panel and the amp. Rediculous.
    Don't do this.

    Hayes
     
  13. TX_TLC

    TX_TLC

    Messages:
    1,475
    Likes Received:
    8
    Joined:
    Apr 29, 2003
    Location:
    Texas
    That is just what I was afraid of... :doh:

    Hey it is still a cool install. I know how it can be when you get a project in mind and you just run with it...it is hard to stop and think is this the best way to do it.

    The sound is the most important thing!
     
  14. slambson

    slambson

    Messages:
    175
    Likes Received:
    0
    Joined:
    Apr 29, 2004
    Location:
    Pocatello, Idaho
    I had a large amp in the same location. Fried this spring during a wierd deluge, although there was not much water inside the panel. I thought I had it sealed up pretty good too. Cadence Z1200 for reference with an internal fan. I'm using several smaller amps under the third seat now.
     
  15. OTEP

    OTEP

    Messages:
    221
    Likes Received:
    1
    Joined:
    Oct 1, 2003
    Location:
    Philippines
    This is how one of the local 80 owner's mounted his subs. Not exactly stealth. But I'm pretty sure it has enough SPL to satisfy most people.

    The amps were mounted on the underside of the troop carrier seats.
    173DSCF01631.jpg
     
  16. Hayes

    Hayes

    Messages:
    2,348
    Media:
    8
    Albums:
    1
    Likes Received:
    568
    Joined:
    May 7, 2005
    Location:
    South Jordan, UT
    Yeah. Definitely not stealth. I'm sure it really cranks.

    Everyone's got different needs for their cargo area. I still want to be able to chuck firewood/rocks/tools/muddy boots/snowy boots/coolers/toddlers in the back without worrying about poking a hole in my woofer or shorting my amp.

    So I opted for stealth and zero cargo area loss. Even if it looks a wee bit ghetto.

    Hayes
     
  17. reffug

    reffug

    Messages:
    3,925
    Likes Received:
    10
    Joined:
    May 28, 2004
    Location:
    'in dat der briar patch'
    Hayes nothing ghetto about your set up its called functional and I think its perfect.

    When I go to put my nak 8" in thats how I'm doing it.