6G Celicas Forums

So I have big plans for my audio system for my car... I am going to run 2 10"s in the trunk in custom fiberglass housing, and add two 5"x7" into the hump in the back seat, add upgrade all speakers in the car.

This is the early stage of the build i dont know what i kind of anything i will be running, but i got hook ups at car toys at get crazy deals(like my 800+ alarm i got for 350 installed) So anything i add will be high end, keep that in mind. My girlfriend runs 1,000 watt amp off two tens and they sound great, since i have a smaller car i figure that running 1,000 watts plus a 8.2 sound system should be freaking awesome And yes she loves to throw it in my face that her stereo kills mine

Part 1. Subs in Fiberglass
I want to palce subs up by the hinges for my trunk, right above the wheel wells, i think i can fit some slim subs in there, or maybe evern full sized... If i mount them up there should i build a metal bracket to hold it in place then build the fiber enclosure around that? What are some of the Pro's and Con's of having subs in fiberglass enclosers? Does it hurt the sound quality? Could i break the subs out of the fiberglass, or crack it?

ok imagine that but surrounded with fiber glass to make it look like it belongs in the car:)



Part 2. 5x7 in the back.
I am planning on taking out the bottom half of the back seat and cut out the center part of the hump. the distance between the two lines that run down the middle of the hump are like 4.75" apart so i am planning on cutting all of that and then some to make room for the two speakers. This way i will keep the back seat looking and feeling mostly stock. I am planning on running plexy glass where there use to be soft padding and middle back seat, so that the speakers will mount onto that so you can see the speakers(and sit on them, the only downside).

So has anybody taken out the bottom of their back seat (i have coupe, not sure if that matters), if so is there so long process or is it straight forward?

kinda what i am thinking here



Part 3. Power
I have red alot of forums where people drop in these huge systems the cant power them off a their stock alt, i do not feel like going through all that trouble untill i have to (IE when it goes out, then i'll put in a nice one) So i was thinking i could just run a second battery to power my sound system. I could find alot of info on how that would get wired exactly... Would i have to wire my head and all my speakers, subs and amp to my second battery then have a kill switch for it? Then i would just run that untill that battery died? Where do most people put it, i was think under the passenger seat... or under the hood?

I am sort lost on how that all works, if someone could explain it to me just how running a two battery set up would work tht would be amazing, because i think that is the way i want to go for power.

Part 4. Amp
Generally speaking here, With all of the above mentioned speakers and subs would 1,000 watt amp and a good head unit be enough to power everything or should i plan on going much bigger??


Again sorry for the bad pictures and those are by no means what i will be buying for this, those were just quick googled images. Thanks in advance for the advice and suggestions

This post has been edited by Legit94GT: Feb 29, 2008 - 12:19 PM

I'm not so sure you can run two batteries off the stock alternator either... I am SO not an expert in this, but I actually think you should ask your Car Toys hookup about the power thing in addition to people on here.

As for the two 10s, I'm running two 10s in my hatch and LOVE it... be sure to balance them well w/the front and rear speakers though, they can easily overpower the rest and just sound like crap. Just my 2¢

I am going up to see my hook up next weekend to figure out just what i will be running equpiment wise and such, but i've never heard her talk about running two batteries before... oh and ps i have heard your stereo:) before you did;) ha ha:)

I'll tell you what I know from my experience with my 6gc.

The stock alternator is a joke. If you do not upgrade your electrical system to handle that kind of power you'll just ruin the battery/alt anyway.

If your going to run 1000w RMS, at 13 volts the draw will be 76 amps continuous. If you drive a manual, you only have a 70 amp alternator! (Auto is 80amp i believe)

Keep in mind this does not include the power requirements to RUN the car, or even power your head unit.

You can keep it stock, but your car will suffer from voltage drops from bass notes and at the same time, the voltage drop will cause your amp to work harder to do what it is trying to do, making it hotter than it needs to be. This also causes the overall quality of the bass notes to suffer...

Now that I lectured you on power -

part 1 - user fiberglass and do it right

part 2 - thats a cool idea i never thought of that. It would make the back louder than the front so for it to sound "right" you'd have to keep them turned down a bit, just my 2 cents.

part 4 - Im a rockford guy. I also like kenwoods... and 1000rms is serious power. I run with half of that and the bass is MORE than enough lol.

Besides if you go any bigger your power problem will only be worse.

If your interested in after market alternators, check out powerbastards.com - they made one for me.

good luck!

I've done alot of fiberglass sub setups, and the only advice i have for you there is LAYER!! after layer after layer. You also need to "Oreo" the fiber if you want it to last. Yes it will crack if it's too small. Also, start with a fleece blanket, then fibercloth a billion layers, fill, Then a million more layers.

As for 1000 watts, im running 1500 right now with no power problem, I also have a 1.5Farad capacitor. If you dont know, it's like a batter, but designed to run electricity faster, and on less of a draw. So thats the best way to do "2 batteries" setup. Rember that your battery is only there untill you start the car. Afterwards, your altenator takes over.

Oreo my fiberglass? I dont get it...
And yes i plan on doing a million layers, i only want to do all that noise once:)
Would a metal frame built off the car wall to secure the sub be a good idea?
Cause the fiber would have to hold all the wait all the time then 2 or 3x the amount of the sub when i go over bumps, so i was thinking build a frame to attatch it to the car then the fiberglass would go around it to make it look like it was meant to be there...

Comments on that thought?

And would porting the fiberglass help with the bass at all?


Good info bman. I really dont want to buy a new one if i dont have to... but my car will be tore apart when it gets turbo'd so i guess i can have them throw a new one on...

As for running two batteries i meant like a stand alone battery system that powers strickly car audio, as in its not hooked up to the alt... that is what i was thinking when i read about a two battery set up. Would that work or would i just kill the battery in 10 minutes:)

Problem with running the speakers in that hump bit. If you have them one above the other like that you'll lose the stereo effect. it'll be loud, yes, but the sound quality will go down.

Oreo is to use a different method of laying fiberglass within the layered sheets. Also called sandwitching. But i like oreo~ It's designed to make your fabrication stronger. I also do this when i fabricate body peices. But for a sub setup, you actualy want more!!

Say you lay sheet for your structure, then use the cutNpaste method for your first enforcement, then use fiberball (soup) method next, use the cutNpaste method again before laying your last fleece sheet. Oreo!

If you run a stand alone battery to the amp, then it will be dead within 30 minitues. If its wired in conjunction, it wont do anything but let you lissen to your music longer after you've turned the ignition off. After you start your ignition, your battery may as well not even be there... Why do you think people change there batteries with the car running? It protects your alternator from dead start alternator death.

Get a capacitor. This is My opinion, but my headlights dont dim out when my bass hits either~

Also, Porting wont do you much if any good if your setup is in your trunk. But if you dont then Make sure you have your echo points lined up; with a step(s) if need be. otherwise it WILL sound like crap.

As for metal brackets, I've always used wood to make a skeleton, It's always worked. I've never had a box break... Except one time but they needed a saw~ After you get the body of the box built, leave room and drill the box directly into your car, and bolt it down. Make sure you use at least 3 point attach per side touching the car. More is better, but atleast 3. Minimum, otherwise it'll bounce all over the place!!

This post has been edited by D-Man: Feb 20, 2008 - 2:03 PM

Capacitors SUCK. They drain WAY to quick and then your back to draining the battery. I ran 2 batteries in the Celica with the stock alternator running all day long with no problem. I had a kx1200.1 kicker amp running 2 L7's (1440 watts rms btw) and had no problems what-so-ever. All you have to do is run a power wire from the front battery to the back battery, and have a good ground. That way the front battery will charge the back while the car is running.

Just my .02

Ya i totally thought about having those speakers stacked liked that and the sound quality but i think they would just look so freaking sweet that i'd get over it



Good info, thank you. I think i will run a setup like that... i'll probablly put in a better alt when my car is all tore apart getting turbo'd. so that will help... and what is the worse that'll happen, i have some power drops and stuff when i first put it in, then i just go buy a bigger alt, so what if i have power drops for a day or two...


Thanks Dman for the fiberglass help, i have never done it before but am looking forward to trying it out and making it it will be fun, i have a cool idea on how to get the shape i want from it...

I think i'll just fab up a custom bracket to secure my sub to my car, seeing as how i have access to full metal shops and have been working in them since i was 15 it wont be hard for me to do at all it should be pretty awesome

Update: I am going to visit my connection this weekend to price everything out and to get the ball rolling with this sound system build I have some a new idea for the two extra speakers i want to add in the back, but they arent going to be in the back seat hump anymore, you'll have to wait to find out on these

So I have been doing some reading here and have just two more questions to ask here.

1. Since i will be running two 10's in the trunk when i replace the 8" door speakers i do not need to make them 8"subs, i should just keep them as 8" midranges?
A. I cannot find any 8" round mid ranges... help...

2. If i am adding two more speakers in the back area, mostly likely two 5"x9" should i put in two 4.5" speakers in the front doors? Or would that just be over kill? lol