Hey all,
I am working on an audio project that im hoping will end up like many of the other owners...it will be a piece of plywood, with hopefully 2 6x9s and 2 subs and a cd changer, which ive already put in. i dont know anything about wattage, but i do know that my stereo head unit only puts out 100 watts. its a custom autosound usa 5...what does that mean? i would like to put the 6x9s in sometime over xmas break but the ones i looked at in the store said they required 300 watts. does that mean i wont be able to use them without a higher amp, like 700 watts or something? Also i heard something about headroom, so how much headroom would i need? what would happen if theyre under or over powered? Any insight anyone can provide into my dilema would be helpful. :?

do yourself a favor, go to a real car audio shop and have them explain things to you, then go to best buy and buy........

I agree with going to the local audio dealer then off to best buy. BUT, plywood? NOOOOOOOOOOOOOOOOOOOOOO, Plywood isn't good if your putting subs and 6x9's (and hopefully your making seperate boxes or compartments for both). A good sub box is made from 3/4 particle board (I think thats what they call the wood-stuff ;)) and then with some sound-deadning material inside of that. There is a site on the net that has the info for building your own boxes, which I recommend because you'll kick yourself in the butt if you make some cheapo boxes and put in a premium system. Check out this site for box-building, excellent tech article - http://www.bcae1.com/ .This site has changed allot since I originally found it but it has a vast amount of info concerning audio.

Thank you for your help Mort, i was planning on builing some sort of enclosure...ill do some research.

speaker are rated in watts lets say for instance a box for a speaker says 500 watts. that usually means the speaker can handle a peak of 500 watts, but they can't handle a continous 500 watts.
rms power is what the speaker can handle continously. usually a smaller wattage then the peak.
amps are also rated in watts. they have the same concept of speakers they have peak power and rms (continous). peak being how many watts it is capable of putting out and rms how many watts it will continously put out.

i hope this clears some of it up for you but i would still go to your local car audio shop and talk to them.

peace
paul

It is recommended that you have enough peak watts in the amp to be available to the peak watts that the speakers want. So if you pair of 6x9's have a peak power of 300 have atleast a 300 watt amp. I have a 400 watt and i am able to run 1 10" and 2 3way 6x9's that have a peak of 220 per-pair. If I crank it all the way up the safty will come on and quickly stops the sound. I hope this is a simple easy way to determine what wattage you need.

BTW the watts that come out of the head unit are only used when the speaker are connected to it through those pigtail wires. If you're going to run everything off of the amp the head unit wattage doesn't apply.

yes that does help, thank you...i was trying to see if my head unit would be powerfully enough to power all that aparently not.

Most head units only put out like 45 watts, I really don;'t know what someone would do with that. You need POWER, get lots-n-lots of big amps and turn up the power (joking). Really, all you would need is a good 4-channel amp (maybe one that peaks at like 360 to 400 watts) with enough watts to run both front and rear speakers and a good healthy amp for subs. You don't need 1000 watts going thru your subs because that wont impress anyone. Allot of affordable subs peak out at 300 to 400 watts, which is plenty enough THUMP in the small 'camino cab.

Now-a-days you don't even have to buy seperate crossovers because most amps have them built into them (crossovers take a single music signal and filters them into 3 seperate signals, low, mids and bass). Some people, like myself, are going to install these crosovers because WE LIKE music and WE LIKE playing with allot of little buttons :).

Another good idea to think about is getting a good brand-name PASSIVE Eq. (Passive means there is NO built-in amp on the unit, which would defeat the use of other external amps). With this Passive Eq. , you can fine-tune music to meet your needs. A friend of miine has a nice sony head-unit with a built in eq. He was "almost" satisfied with the sound his system was producing, when I asked him to plug in a Eq. that I had sitting in my garage. WOW, what a big difference that made. I did not sell this eq to my firiend because this was a unit I had bought for my sons car, instead, we surfed ebay and bought him one.

Brands that I recommend are either Pioneer or Kenwood. I've tried both brands. There are more brands out there but I'm talking quality on a budget.

A good sub box is made from 3/4 particle board (I think thats what they call the wood-stuff ;))

The stuff you are looking for is called MDF (Medium Density Fiberboard) (http://www.woodworkingtips.com/etips/etip10.html). It can be found at Home Depot, Lowes, etc.. It cuts well and carpet can be easily attached with contact cement. If you want to put your box together with wood screws, be sure to drill pilot holes and countersinks first. If you would rather, construction adhesive like liquid nails works really well instead or in addition to screws. I use this stuff for any project that will get covered or painted.

Yeah, that "wood-stuff" :). I couldn;t remember MFD for the life of me, thanks, I owe ya a b33r:)

it's highly recommended that u use BOTH liquid nails and screws. the liquid nails will not only help the screws keep the box together when the bass tries to expand the box but will also give it an airtight seal. www.the12volt.com has alot of info sbout boxes. as far as the different types, their pros and cons, and also calculators cubic inches.
you can also use 3M spray adhesive to glue the carpet on. rubberized coating comes that come in aerosal cans are awesome for dampening the inside of the box and you can also ad poly-fill to the inside of the box also. there are plenty of web sites out there that offer plenty of advise just have to go out and find it. have for building your system!