I don't know in how mutch time you want it, but here is what we're working on:
This subwoofer enclosure is design for using the maximum air volume it possibly can under the dash (Explaining it's wierd shape) In the picture, you can only see the first piece (The model, the base...) I need to make the molds out of it and when the molds are ready, then I will be able to reproduce the enclosures. Basically, I'm trying right now to sand it, prep it for the best finish it can have. I don't know how mutch time left I have to put in the project but chances are it will be ready to make reproductions by the end of the summer.
As for the cost, I have more than 250$ invested in the project and I think I will invest maybe 250$ more. (This money is only the material I used: Foam, Plaster, Fiberglass stuff, primer, clear...) This doesn't count for the fiberglass I will be using in the products I will sell. So for the price, I don't know right now...
I would want to make some test too, to see how mutch layer of fiberglass will be good for keeping the subwoofer enclosure from expanding too much. And finally, some kind of brackets will be needed for the subwoofer enclosure to be attached in place. (And he is actually quite heavy, and I need to add the weight of the subwoofer, and add some reinforcement just to make sure it won't drop because he is playing or anything)
Now here are the good and the bads: GOODS: -One thing is sure, this subwoofer enclosure is perfect to use the maximum space it can use underdash -You can fit at least 2 kinds of 8" subwoofers -You don't have to put it behind the seat so there is more place for the passenger to move his seat -Obviously, you can put 2.5" more of subwoofers than the original subwoofer enclosure (lol, that's the point of it) -Because it lowers to the same height of the plastic vent used for the air conditionning and heating, people won't detect it as much as a subwoofer enclosure behind the seat. -The modification is hidden, therefore tougher to detect from the outside of the car (If you're planning on going to car shows with an original car
BADS: -You CAN NOT fit bigger than a 8" subwoofer -I can only garenty you that 2 subwoofers will fit in, I didn't tried alot of them -The amplifier CAN NOT be under the dash, there is not ennough space. (I recomend behind the seat or if you want you can put it in the front compartement or even in the trunk) -The subwoofer is exposed to anything, so people could accidently damage it with their feets (I will work on somekind of grill after that for protection) -The modification can easily be seen by the interior of the car (Well, easily... only someone who knows about fiero will know it)
That's all the points I can think about right now, I will write more things when I will do the official post. (When the molds will be ready) I just wanted to let you know that at least someone was in the project!
If you have any questions, I will try to answer them the best I can!
By the way, I DO NOT take waiting list! Sorry guys! :/
Black Pegasus - that enclosure is AWESOME!!!!!! I look forward to seeing it finished and produced! I feel confident that, for the right price, you will sell MANY MANY MANY of these! Alot of people are looking for some "bump" but not willing to sit 6" closer to the dash!
Finally, I took some pictures of the fitting. Sorry for the bright red color, while doing the project and to make a better finish of sanding (Sanding clear makes a better finish and is easier than sanding putty, fiberglass and everything else) I was doing some paint test for my futur color of my Fiero
Here is the hole where the enclosure will fit (Note that you need to relocate the chime module):
The enclosure will go up this way:
Here is the fitting without the dash:
Here is the fitting with the dash:
Now the subwoofer hole:
And now is a important thing we do not want to forget, that above the subwoofer enclosure there is a 4X10 speeker. So we adaped the enclosure like this:
Here is all the pictures I can give you that I can think of right now. I hope you like it. Feel free to leave comments!
This is one thing I forgot to say. Unfortunatelly, the subwoofer enclosure is using the maximum space and is the biggest it can get. Therefore you WILL need to remove the dash. At least, that's what I did for all the testing. I would be actually impressed if you don't need to remove it. But one thing is sure: somehow, you will need to remove the dash to wire the sub, to relocate de chime module and to put on the brakets to hold the sub enclosure there.
And by the way, thanks to everyone for your good comments! Really appreciated!
Fred, I'm definitely interested in purchasing one of those! But it'll have to wait till next summer. I've only got two and a half months left of driving the fiero, so I wanted a quick purchase. Good luck with your product, looks amazing.
A couple questions: Will it work with Fierosound's 5 1/4" Component adapter plate + component speakers? What depth would I have available? At the risk of it sounding like a stupid question: Why wouldn't a 10" speaker fit? Where exactly is the problem? (different angle maybe? little closer into the footwell?) Please explain it a bit. What would the odd shape do to harmonics and sound? Better?, Worse? What exactly is the air volume? (if you haven't tested it, Water, and/or small pellets could help you measure the volume of this odd shape)
G'day from Australia. Have you considered using dowel/s to cross brace the box? If you play with a few different configurations of bracing to find an optimum, you may find it "deadens" the energy that the fibreglass box will absorb which then causes the box to vibrate, producing a sound that is not as accurate.
Also as it appears that no porting is designed in this box (which would be driver specific if you did port). You could try using a high grade, audio specific foam product that will dampen internal standing waves in the box. Damping of the internal air mass is critical in controlling the air flow from the bass driver - affecting bass extension and the speed of the midrange.
If you have the correct driver for the volume of the box, well sorted bracing, good thickness of the walls in the box, and suitable acoustic foam, you may not have the bass of a tuned ported enclosure, but you aught to get a clean midbass and bass from an 8" driver. Of course, the crossover in this circuit with good inductors or if it's an active crossover into a suitably powerful and accurate amplifier will make the world of difference, to handle dampening on the 8" driver.
For the Fierosound's 5 1/4" Component adapter plate with the component speakers, I don't know if they will fit. I don't have this kit/modification on hand so I can't try to fit the enclosure. From what I can see, it appears that it may fit but I can't say for sure. Sorry...
I could not fit a 10" speaker in there. As you can see from the pictures, the space is very limited. The problem was with the combination of diameter / dept and angle of the various 8" subwoofers, we actually had to make a lot of modifications just to allow the fitting of a second type of 8" subwoofer (a choice between shallow or a normal sub). It is impossible to put a 10" under there because of its diameter. The space is just not big enough to mount it (unless you want to cut out your dash and / or the heater’s "duc work" to allow extra clearance) or by bringing it down even more and make like a conic shape to have a bigger hole. An other reason is that, once again, the space is very limited, therefore most 10" subwoofer may not have enough air volume in the enclosure to work properly (There will be too much air resistance therefore you will need more power to drive the subwoofer... The efficiency will go down below acceptable standards). For the amount of space under the dash, an 8" is the biggest thing I can put while staying within the project guidelines.
Rixthetrick is absolutely right. I have not tested if the box shape will change the harmonics significantly. But I do not expect any problem in that area. The only problem that I can see with the fact that the enclosure has a weird shape is the air flow within the box itself. If the air moves rapidly around bumps inside the box, there may be a whistling sound generated by the air movement. This can be easily taken care of with some strategically positioned polyfill damping material. Keep in mind that all woofers will work differently in a given enclosure. The woofer relies (at least partly) on the enclosure for damping. A lot of people just go to a local audio store, pick up a subwoofer and a box, install the subwoofer in the box, connect their power amp and go. This works and often yields good results.
However, if you are looking for optimum performance, this box will be no different than any other box, you will have to pick up a subwoofer that operates within the air displacement availability of the box AND will need to “tune” your subwoofer / enclosure combination to the type of music that you listen (by damping the enclosure as required for your combination).
As for the volume of the enclosure, there is currently no way for me to know the exact amount. What was pictured above is not yet a working model of the enclosure, it's a pre mold model. We made quite a few modifications to the model by adding putty to ensure that both of our subs fit AND to capture the maximum available space under the dash. Therefore we added putty over the existing fiberglass pieces. This means that in some portion of the enclosure, the "walls" of might be as thin as 1/8 inches and some other portions might be as thick as 1 inch! For this reason it is impossible for me to get an accurate volume reading by putting the enclosure in water because it will show the exact exterior volume, this will have a higher volume than the air volume inside the enclosure (Because it will be the exterior volume, it doesn't account for the material thickness I will be using). Plus we may have to add some extra strategically positioned reinforcements inside the enclosure to "tune" the enclosure's reverberation (vibration). I can't pour water inside the enclosure because it was HEAVILY modified. Having that much variation in the enclosure "walls" won't even yield a volume estimation. Basically, I can't give a proper volume estimation until I have a "close to final" product, and the volume won't be exactly the same from one subwoofer enclosure to the next (because of the variation in thickness of resin and fiberglass used when laying the enclosure). Though, I'll make sure to have nice layers of fiberglass to have the strength needed to withstand the force of the subwoofer.
If you guys have any other questions, I will try to help you the best I can!
Black Pegasus, sounds like an exiting project. Can't wait to see (and hear) the results. Keep us in the loop. Which subwoofers are you tuning/designing this box for?
Since this box is so huge it might allow for some medium/high end subs as well. (This will make things easier down the road once the medium/high end speakers drop in price)
As to Fierosounds 5 1/4" enclosure: See if you could contact him, or one of the many members that have it installed to give you the measurements necessary. I'm assuming that the only problem will be depth (or where the depth would be) You could probably make a mockup out of cardboard and use it as a template to make your measurements from. (It's a Word document anyhow)
Keep in mind some medium/high end drivers, such as Polk SR-series, Infinity Reference, Alpine R-Series, maybe even Focal (although they tend to be priced above and somewhat tinny sounding) Since most high end drivers tend to be bigger than normal drivers, that should give you plenty of slack to work with.
Please also post some info about "tuning" with Polyfill, or special material once time comes.
Try pouring rice into the enclosure, it will give you the internal volume without creating whatever issues water would have on a fibreglass box??? Also if you're worried about whatever you're bracing getting waterlogged - paint it with resin, I usually do that with dowel anyway. Are you thinking of lining the box with something affected by water (moisture)?
Poly wool will not nearly give you the same results as properly designed denser "sticky foam". Which you can hold up to your mouth and talk through it, and a second person can audibly discern a difference in pitch. If you can't hear a difference in pitch in the product you're going to use, I assure you there are products that will, and absolutely make a difference. More so to the lower midbass than the lower inaudible frequencies.
Yesterday I found a solution I have chosen to run with, after I source it for the best possible price. Of course it's my best compromise, my car is Right Hand Drive to meet Australian rules. The area this box fits has all been changed in my particular car. Therefore I couldn't possibly use this sub box; otherwise I'd be lining up to give it a try.
This sub enclose is made for high end sub. It was design to fit a shalow 8" subwoofer and a "deap" 8" subwoofer. Here are the 2 subwoofers I'm talking about: -Pioneer TS-SW841D (Shallow) -JL Audio 8W3v3 (At 4 Ohm)
I will do my best to comunicate with Fierosounds, try to make some fitting... At the end, I'll try to do my best to respon properly to your requests.
For the other subwoofer, I will try to go over many brands of car audio system to see statistically what other subwoofer could fit in there. (By statistically, I mean by calculating the specs of the subwoofers. Though they will not be tested therefore I can't garentee it fits properly without any modification on the enclosure. I can't even garentee they will fit at all. It's just to give an idea of what could fit if you already have the sub, or you really want this sub option, or if you are a handy man and you want a little project. Basically, a list that will fit without many mods or maybe even without mods, who knows!)
For the tuning, I'll tell you guys when time will come. Because the Pioneer sub might not require as much damping or even no damping at all... Or this situation might happen with the JL Audio sub. Every subwoofer will react differently on the same subwoofer enclosure with the same given air volume and the exact same shape. Therefore the damping must be adapted differently to one sub to the next. The problem is not with the water itself, it's more of a poblem with the extra material added. Here is a picture to show you: (I made it fast on Paint at midnight just for a visual support)
This is the example of the bottom of the enclosure cut in half (Where there is the hole) if you would watch from the passenger door to the enclosure. Because we needed more spacing to put the shallow one. Here is the ledgend:
Blue = Layers of fiberglass gray = Fiberglass resin Red = Gelcoat Yellow = Filling Putty (Used for body work) Black = Where the sub hole will be Green = The space unable to be counted if we test the volume
(Note: The final product will be only made out of Fiberglass, Fiberglass resin and Gelcoat, these are waterproof and are not affected by water)
Basically, we made a first rough shape with fiberglass and gelcoat, a rigid base. When it was time for the modification (To take more place out of the underdash) in this case it was to be able to put the sub too. We needed to tilt the sub box to make it fit so we added extra putty for the support where the enclosure will screw on.
By adding this putty, if you put water, or rice in it, it will show the volume of the inside of the enclosure (In the diagram, it would be the upper gray portion represented by the fiberglass resin). This means that all the extra putty we put would be ignored, useless. In the final product, there won't be putty so the enclosure should like more like this picture:
The green part is all the extra space we made and can not be counted right now because of the material taking the space.
As you can see, there is alot of things modified, and we can't put all the sub in the water because it will show the exterior volume (The bottom yellow part of the first picture). Yes it will be the exact same exterior volume but the interior will change because you need to add the thickness of the material (fiberglass, resin and gelcoat) Therefore in both ways it won't give a proper volume reading.
It's not only the bottom that had been modified, here is a photo of the enclosure:
In this case, the red is the gelcoat, the pink is all the major putty we put on and the yellow is the finishing putty. I don't know if you guys understand, if it's explin properly. It's pretty hard to explain. If you don't get it, just tell me and I'll give it a second try to try to help you!
Rixthetrick, I'm sorry that the enclosure won't fit for you. It's such a nice project I'm so excited with. I can't wait to hear it! But I would of hoped to have someone who has alot of knowledge in the subject and expertise to try it, make a critic of thing that could be ameliorated, or things that are awsome. You can still fallow the subject and post, if you have anything you can think of.
There was little that was done on the project for many reasons: -I've developped severe back pain -I've got sick (Flue I think) -School started
Though, as all Fiero owner, the family is involved! (My father has some, my brother, my mother...) And this project was for our Fieros at the begining, (The 4 first enclosure that will be made will be for my family member and I) so I don't have to tell you how mutch everyone is pretty excited about the project! My father was my partner on this one and he made an awsome work on it.
Just because I am an awsome son ( ) and I love to make surprise, my father took vacation today and he will not be home for a couple of weeks, therefore I will try to make as mutch progess as possible and hopefully, the mold will be done when he'll be back of vacation! (I don't know how this surprice will work out due to school problems, my priority is there, I'm sorry... ) But, I'll do my best! (These weeks will be my self-kick in the butt to move on the project! :P)
Progress: First off, I've made some remarkable sanding, 3 out of 6 faces are ready to be polished and the other 3 has only little bit of sanding. (But still, I'm not starting from skratch! )
Next step: Sanding the 3 other faces!
I like the fact that you are still interested in the project, I really apreciate, thanks! I'll try to get some pics of the enclosure when he will be all sanded. Fred
All faces of the enclosure has been wet sanded with 400 grid sand paper. It has beed sanded with a hard sanding block to remove all the defects in the bad clear coat I painted... ( ) lol
Next step would be: Sanding with an even smaller grain of sand paper (We can still see all the marks left by the sand paper) I'm guessing a 600 sand paper will be ok, if not, I'll go to 800... 1 000... PLEASE hopefully I will be done and I won't be forced to go to 2 000 grid! lol...
As soon as the sanding is done, I will post some picture!
Once again, I'm sick (Damn, twice in a month? fortunatelly it's not H1N1! :P)
The only thing I can tell you as update is: I've polished 2 faces of the enclosure (Polishing alone is quite difficult because it moves everywhere on the table, I'm just waiting for my father to come back for his second vacation for some well placed help! )
After that, it will be officially the time to start making the molds! (Unless there is something wrong or I'm forgetting something... :P )
I don't know if a subwoofer is better than an other one, nothing have been tested yet. Though, I just have this feeling that a 12" subwoofer made by Alpine would sound GREAT!!! (too bad it doesn't fit... ) I will test the 2 model of subwoofer and we'll see from there... Though, I will try to give you all the mesurments (When the enclosure will be ready) so that you can fit in your own subwoofer if you want to. (So Austrian Import, with these mesurements, you will be able to figure out if your sub fits. The reason I am doing it this way is, I don't want to be responsible if the sub doesn't fit. This is why I'm only taking position on these two subs, because I know these will fit. Though, I'm not really recomanding this subwoofer [The JL Audio 8W7] because because it requires around 0.875 cubic feet of air to making it work in optimum performance and our enclosure just isn't that big enough, we have around 0.3 cubic feet. You will need a MUTCH more powerfull Amplifier to drive it and it won't be good for the subwoofer and the subwoofer won't work at it's optimum performance. But this is my opinion, I wouldn't do it, you can if you want, I'm just giving you facts. [Sorry if this seamed harsh somehow or if I desapointed you.])
I have calculated roughly the air volume of the subwoofer and it's close to 0.3 cubic feet. This mean that the two subwoofer that I fitted in will not require a ported enclosure. (Wich is good because there is no space to fit a tube! lol) Though, it's possible that the enclosure can be bigger than 0.3, or it's possible it can be slightly smaller. THIS IS NOT A DEFINITIVE AIR VOLUME MESURMENT! (I'm not yelling, I just want to make sure everyone understand this. Sorry if you get offended) A better mesurement will be taken when the first production subwoofer will be made.
The weight of the subwoofer will certainly matters. I just don't know how mutch it will matters. It depends on how mutch layers of fiberglass I will put in there. I juste know that the magnets is significantly heavy. This is why, again, some test will be needed to be done.
If you have some questions, comments, suggestions or if this didn't quite answered your question, just let me know!
EDITED: For links...
------------------ 87 Pontiac Fiero GT
[This message has been edited by Black Pegasus (edited 10-29-2009).]
high end 8 will sound cleaner and be able to carry as much wattage as a low end 10 or 12 if not more and still sound better. Loudness one thing clarity is another thing all together. The problem with that speaker in an under dash set up is the weight of the speaker and air volume required for it to operate, That 8 probably tips the scales at near 20 lbs and I would hazard a guess that it requires at least 2+ cf of airspace to function properly. There are shallow mount options that are lighter and require less volume in the box, The big thing to look at is frequency range, wattage peak and wattage RMS and is the speaker dual voice coil vs single voice coil. Dual voice coils tend to hit much harder due to the design.
[This message has been edited by Macs86GT (edited 11-02-2009).]
EDITED: I've posted before seing the post of Macs86GT (By the way, you are right Macs86GT)
The problem with the JL Audio 8W7 subwoofer, I don't think it would be fitting it. I think there is a way possible to fit it in the enclosure. Physically, I think (I'm not a 100% sure though) that this subwoofer will fit with some modification to the enclosure. The only problem I could see though is the air volume required by that subwoofer.
I have an enclosure able to contain about 0.3 cubic feet. But this subwoofer require 0.875 cubic feet to work in it optimum performance. This mean, even if the subwoofer fits in the enclosure, he is missing 0.575 cubic feet of air to work with. This means the music notes won't sound like it should or as loud as it should. I can't make the enclosure bigger (As you can see in the pictures) because I'm already using the maximum space available under the dash.
In other word: -This subwoofer might fit if we work on the enclosure a little more. -The weight won't be a problem if we design some kind of a metal bracket to support the enclosure and the subwoofer. -The enclosure does not meet the requirements of the subwoofer: Thus you will need an extremely more powerful amplifier to run it.
------------------ 87 Pontiac Fiero GT
[This message has been edited by Black Pegasus (edited 11-02-2009).]
Black Pegasus, how much would the enclosure stick out to get the minimum box requirement? Or even 1 cubic foot?
I'm not dead set on any single subwoofer yet, but I have to admit, I'm in awe of what the 8w7 can do. http://www.audiogearreviews...iew-JL_Audio_8W7.asp (click through to page 2 for thorough review) It's a couple of years old though, isn't there any other subwoofer that comes near those specs?
Also, how do you amp it at 3ohm? I've only seen 2ohm and 4ohm amps before.
I'm afraid this subwoofer can not be made to fit under the dash. The only way possible to make a subwoofer enclosure big enough is by: -Make some modification to the air duck work. (For the heater of the car) -Fit an other (Or custom) dash. -Make the enclosure go down even more until it reaches the floor of the car.
I am honnestly clueless about this one. Honnestly, I would like it to work (I would get myself one too) but I just don't see how we can pass the fact that it's missing some drastic air volume within the enclosure.
Black Pegasus, could you modify the air duct flap to take up less volume? (the one where you already removed the mounting bracket) Or make it curve so it lets the speaker have more room? How much more with would you need to get the extra .5 cubic feet?
Modifying the air duct flap in possible but complicated. The less it takes place, the less air will go into the air conditionning and all this stuff. I don't think I will gain much more air volume within the enclosure by doing this. Just to give you an idea on how much more I need, the photo shows a 0.3 cubic feet enclosure. This mean, I need an enclosure at least twice bigger! This is a lot of place...
It's quite tough to make a great sound system in a Fiero because the space is very limited.
I honnestly don't know how to make this enclosure big enough..