Hey, this has probably been asked before but I'm asking again in hope for some new posters. =) I'm trying to plan a speaker/sub setup in the rear of my '79 that can handle 2 6x9's, 2 10" subs, and most likely 2 amps. I must be able to fit my T-Tops in also.

I was thinking of building 6x9 boxes so they could fit into the corners by the wheel wells and take up very little room. Doing this...I could build boxes aginst the back wall for the 2 subs and have them raised about 5-6" so that I can stack the T-Tops and slide them under. This would leave about 6" for the height of the sub box, and about 25"-30" for the width, and 13-14" for the depth. Does anyone know if they are any good subs out there that require less air space than most? I've also heard of stuffing boxes with fibreglass to slow down the sound waves which can increase virtual air space 15-20%.

Please share your ideas, pics, comments, suggestions. thanks!

 

if you're going to put 2 10's in the rear forget about the 6x9's that's just a waste of cash, insted use it for better front speakers or something else.

:cheers:

 

You don't think so? I was planning on replacing the front 6x4's..? and adding two 6x9's in the back also. Anyone else have any comments on this?

Nobody else has anything else to share? come on... =)

 

oval speakers are bad for sound quality

 

Gee, you don't want much do you? :p:

If you have the subs, you won't need the 6x9's. Use some 6 or 8 in round speakers instead - maybe splits?

:cheers:

 

How much custom work are you willing to do ?? Cause you can get a nice component set for the front, 5 1/4 will fit in the kick panels just need to cut them for install, then fab up a mounting plate for the tweeters in place of 4x6's for a more stock look. they'll sound better than the 4x6's and you'll have all the mid/high range you need to work with the 2 subs in the rear. If you want i'll give you a break down of the system i'm putting together for my car.

 

I am willing to do alot of work to get it just right. Just can't really do any fibreglass work....any wood-working I can do, have all the tools and I can get all the supplies I need. Please share your plans.

 

You'll have to make a custom box for the subs, but you don't really need to worry about enclosure space, as long as the subs are facing up to the rear glass you'll be fine. With the large glass and shape it's perfect for subs. Then like I said before you'll have to cut the kick panels for the mids and make a plate to mount the tweeters to to replace the 4x6s.

Ok, here's what I'm putting together a peice at a time:

Hi-output Alt. 180amp off ebay for $130
Optima Batt. found for $105.00 on the net.
2x 1 Farad digital caps from RF $115 ea. ebay
JBL 1200.1 $255 ebay
JBL 180.2 $140 ebay
Audiobahn ABD40X $140 on the net.
HiFonics Zeus HZCX5.2C $80 ebay
MTX T6103A $270 on the net
Alpine CDA-7995 $370 ebay

plus all the misc fuses and wiring, puts the total system in at around 2k :D

 

hmm, yeah I was thinking of making them face upwards and putting them as far back against the back wall as I can.....are you positive the air space won't matter? I'll probably end up with like 70% of the airspace that the subs recommend. Can anyone else confirm that the shape of the rear makes up for lack of air space?

thanks.

 

What I think Metal_Wulf is saying is that the rear glass is good for deflecting bass if the subs are firing upward into it. Yes, that is true, however, it won’t compensate for lack of airspace. The best you can do for that is to pack the enclosure with pollyfill. Look for a sub that doesn’t require a lot of airspace in a sealed enclosure. Try IDQ10 or RF HE 10” line. Just two suggestions, there are more, just shop around.

 

Here is what I did. 2 10s, 2 6x9s and 2 amps, just like you said. With room for the t-tops.

 

Pat, I saw your design and it inspired me to make one similar. Do you have the dimensions of your boxes? Is it all one piece? Are the two subs in seperate boxes? How much air space is in each sub box? What type of subs are they? How does it sound? Please share Pat! =) Great job man.

 

The sub box was built seperate with outside dimensions of 8"H, 24"W,12"D. There is a divider in the center of the box so each sub is in its own enclosure. Each side comes in right at 0.5 cubic feet which is on the low end for the speakers I have but they still sound good. The subs I have are Advent 10" and I got them for free so I could not complain. If I blow them I will just get something more mainstream, but for now they are fine. The side shelves were made by first cutting a cardboard template to fit over the wheel well, one in front and one against the back wall. Once these were made I then made a shelf on top. My shelf drops down 2" from the top of the sub box to hold the amps on the sides. This way the shade it still operational and the whole thing can be hidden from view. Construction was with 1/2" MDF, screws every 3" and silicone. One 1/4" hole in the rear of each sub partition for the speaker wire to enter. The 6x9s were kind of a pain. I built a slanted shelf underneath the amp shelf and mouned the speakers underneath the slanted board. If I did this again I would most likely get some component speakers, like a 5" mid and a tweeter and just point them forward. Would make the comstruction easier. Finally to install, I placed each side shelf and slid, actually forced, the sub box in between. It is somewhat of a zero tolerance fit so everything is tight. A couple of L braces on the rear board of the side shelves provides support for the rear sub box, and I also secured the front together with some 3" flat braces. So once installed this is all a single unit. The opening under the sub box is 25"x4.5". If you stack the t-tops they will just slide under the center section. Once I was done I found the extra carpet from when I redid my interior years ago and was lucky enough to have enough to cover the whole thing. The grills are quite unique being welded stainless "v-wire" from a my neighbors business. Hope this helps with ideas for you. I do not have any drawings, kind of just built it as a went. It helps to have a table saw, band saw and a good jig saw.

 

Thanks alot Pat! I plan to do something very similar to you...I will probably construct it different, but the finished product will look very similar.Yours is definately the best system I have seen in a C3 without doing loads of fibreglass work. I'll most likely use some mids & tweeters in place of 6x9's...since the friendly folks in this forum assured me 6x9s are not needed if I have 2 10" subs. Thanks, again...

-I'll post pictures of my finished system when it's done. porbably won't be for a while though...I need to get the money first. ;).