People have been asking this quite often, and the photos on my website obviously don't show clearly this information. I had my seats out to shampoo the carpet and took new photos as below.
At location I & II it is 3 inches from the FRONT of the console to the front of the sub-box. At location III it is 4 1/2 inches from the bolt center to the front of the sub-box. In the second photo you can see where the front of the sub box is relative to the seat belts on the side panels.
first of all, your system is the best!! i need advice. i have a fiero as a weekend car. it has roll bars along the interior from front to back 'cause i cut the top into a full targa. looks great, but now it's time for the stereo setup. i want to make a box out of the area where the back glass is and wall it out with two 12" subs. i think it would be more show than quality, but it's better than nothing!! by the way, my car is on the radical side as far as customizing goes. the interior has been redone with black, white, and yellow accents. any suggestions??
Hey FieroSound... I fianlly have almost finished my set-up similar to yours (need to vinyl) The lower section has the sub while the upper houses the amp.... all in one nice neat unit. Should have pics soon. (need to finish rolL) It rocks HARD with 2 JL Audio 10w1's
FieroSound, I have been toying with a similar idea, though I am not looking for a real boomer, just some more bass. Your install is great real clean and neat just the way I like to see things done. What did you cover the boxes with? How did you attach them to the back? I was actually thinking of get this a big chunk of VELCRO. Keep up the good work
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12:40 AM
fierosound Member
Posts: 15145 From: Calgary, Canada Registered: Nov 1999
I attached the boxes to the firewall with sheet metal screws, but I used alot less than Loki http://www.cox-internet.com/fiero/mystereo.htm and once they're in, they're there forever!!
I covered them with unbacked carpeting, using a high quality spray adhesive. I also recovered the door panels with the same material. As I had installed speakers in the kick panels where the footrests are, I ordered new matching carpet without any footpads as well.
If you decide to install subs this way, here's a better breakdown of the work involved.
Tools you need:
- electric drill and bits - electric hand jigsaw - wood and metal blades - table saw or electric hand saw - hand saw - tape measure - 3/4" MDF panel (Medium Density Fiberboard) - wood screws, metal screws, wood glue, silicone - cardboard from appliance box is useful
The interior of the Fiero is not "square", so I can't send exact sizes for anything. You have to build the boxes into the car while the interior in the rear section is removed. Removing the seats gives more room. If needed as a daily driver, you may have to remove/reinstall driver's seat several times as you work.
Once the interior is out, what needs to be done becomes obvious if you follow the information at my site.
The gas filler pipe runs through the area on the driver's side - be careful!! To cut out the firewall, drill a small hole about 12 inches up from the floor. Insert a wire coat hanger to "feel out" how large an area you can cut out. Use and electric hand jigsaw. It's better to start small - you can always cut out more.
The "well" is in an 8" or 10" inch channel supporting the firewall. Each end needs to be sealed. Cut some MDF to fit and silicone into place. Some people are using fibreglass to to this - probably easier. You need to seal this - otherwise all your bass will be "outside". There is limited space for speaker magnets. Buy high efficiency speakers with small magnets. I recommend OZ Audio 10" 250L subs because of their excellent specs. http://www.sounddomain.com/shopping/product_details.cgi?sku=OZA250L&sidebar_
"Try out" how/where speakers will fit and take measurements. You can use cardboard to help "size" the box you will need to build. This can then serve as a template to help build the MDF enclosure.
Build the "frames" first - make sure they fit properly. It'll take time to shape and trim them to fit snugly against the firewall. THIS IS THE MOST TIME CONSUMING BUT MOST IMPORTANT PART!!!
Attach to firewall with sheet metal screws. Don't forget to get your speaker wire routed into the sub box at this time. Seal firewall/frame joint with silicone to make sub box airtight. This is where proper fitting helps installing and sealing.
Make your front panels. Also determine what you will do across the top below the window to finish. Keep in mind you need to install speakers from the front - so you can remove them for replacement. Determine how you want to mount speaker: - surface mount with grill - sunken with custom grill panel
Check for clearance/fit of panels to center console, wall panels, etc. Attach speakers to panels and check again, making sure everything fits/clears. Make adjustments as necessary so everything fits. Remove speakers (to prevent accidentally damaging them).
Attach front panels to frames with glue/screws. Install speakers again and test run - check for rattles, etc. and fix if any. Remove speakers (to prevent accidentally damaging them).
Cover the sub boxes with covering of your choice. Unbacked carpeting is best and easiest to work with. It can be cut easily, stretched around corners and will hide small imperfections. It can be bought from car upholstery shops and Car Audio stores in a variety of colors. Use a good quality spray adhesive.
Cut and reinstall carpeting - leave enough to tuck under/around edges sub boxes. Install side panels and center console. Install speakers and grills. Reinstall seats. You're done!!!
Hope this helps, Good luck.
fierosound Calgary, AB
[This message has been edited by fierosound (edited 12-16-2000).]
180 watts per sub (360 peak per sub) should be more than enough for anybody. I'm only running 50 watts each! More important, is the 93db sensitivity (efficiency) which means you can get more SPL with less power. Check the specs on some other subs. Those with a sensitivity of 86db (and lower) NEED LOTS of power to work properly!
About your nickname... does it relate somehow to the amount of WATTS and BASS you think you need??
[This message has been edited by fierosound (edited 05-09-2000).]
Are your seats covered with cloth or leather? I'm looking for that setup but I'm worried that the sub will not sound as good through my leather seats. If I install the subs there my seats will allways be all the way to the back (6' driver) and I'n not sure how the waves will travel with the seat back stuck to the grill. Any ideas?
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03:42 PM
fierosound Member
Posts: 15145 From: Calgary, Canada Registered: Nov 1999
The above site give specs for the 10" MOMO (the Competition series) sub from Polk Audio. It has a sensitivity rating of 85db. I'm not sure which model you have.
The rule of thumb in car audio is:
To DOUBLE the volume, you need 10 TIMES the power. That is why 50 watts does little for your sub, as it needs more power anyway. This is where some people get in trouble... they mismatch their speakers and amplifier power. Mine could use more power but DOESN'T NEED IT. If I put it into competition again, I might do something just to generate more SPL points.
[This message has been edited by fierosound (edited 05-09-2000).]
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07:28 PM
fierosound Member
Posts: 15145 From: Calgary, Canada Registered: Nov 1999
Leave 1 inch between your seatback and grill. If you can't, I suppose you need to look a for an alternate method of installing subs.
Most trunk equipped cars fire their subs THROUGH the backseat without any problems. The nature of the low frequency soundwaves is quite different from that of highs and is less prone to being blocked.
No matter what, your bass will have to be better than a car that has no subs at all!
[This message has been edited by fierosound (edited 05-09-2000).]
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07:30 PM
May 10th, 2000
Dan86gt3.8 Member
Posts: 465 From: Waco/San Marcos, Tx (USA) Registered: Jan 2000
fierosound, where do you get the info on where the fals wallis I am gona try this this summer sometime and was wondering where that area is where theres a fals wall.
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12:57 AM
fierosound Member
Posts: 15145 From: Calgary, Canada Registered: Nov 1999
Check this earlier forum. The photo there may give you a better idea about what you get after cutting the firewall. You then have to build the sub boxes.
take a look at the JBL GT subwoofers, or the gti subwoofers. I have a pair of 12" JBL gt subwoofers, they have a sensetivity rating of 97, and handle 300 wats RMS. the new gti subwoofers are a little less sensitive, but have 2X the Xmax of the gt. one of best sounding subwoofers i have heard.
I did the same thing as Fierosound only after seeing his car at his site. He e-mailed me the info on this thread. I used 12" alumapro subs and adjusted the box volume. There are powered with 2 Zapco studio 300 amps each bridged. my car sounds really great. And by the way I never thanked fierosound for the info you made it real easy THANKS FIEROSOUND
Foer some reason the pics that Fierosound has on here will not load up for me. Can someone send me the pics to see what it looks like with these new pictures?
Yes, my car is listed as an install at www.sounddomain.com I think there are 7 Fieros with their sound systems listed there...
Thanks. OZ Audio subs are noted for high-end SQ applications. Anyone who has sat in my car and listened to the system has NEVER made any comments about any lack of SPL or pointed out any inadequacies of the system. (I guess there is none that they can notice) I've taken home hardware (trophies) from every event I competed in (15), including a "1st Place" AND "Best of Show" at one event.
I'd still recommend OZ Audio subs (or similarly spec'd subs) for a Fiero install because they have a high efficiency rating, and have small powerful magnet structures. This is ideal, because there is limited room in the driver's side for a sub magnet, even after you cut out the firewall next to the gas filler pipe.
