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Glass, can you help me with this one? I have a ppi Old school DCX-1000 crossover. I have it set to factory. Now, to set it myself, would i have to look up the speaker, well, jeez, i'm not sure how to explain this, lol.... But i'm going to try:} OK, i want to now if i was to set this and not use the factory settings how would i go about doing this? The crossover has all kinds of settings. If you can remember from your day, lol. Do you look up the speaker specs like 50HZ to 250 HZ or 12KHZ to 5 db. Is that how i would do it or is it just done be ear? Thanks Glass, Steve. P.S. How's the Car Audio Central ‘Live’ Chat working out? How many peple are using it? I'm thinking of joining it.

Steven the x over needs to be set to match the speaker, vehical, and other speakers in your set up. Most of this is done by ear, or with a RTA, except matching the x-over to the speaker. That can be done using a general freq, and slope, and then fine tuning the rest.

So let us know what your hooking up, and we can help you with some general refrences.

Well since the grill is heating up, here is a quick refrence.

Say you have a 12, and a set of 6.5 components. A general x-over set up would look like this.

sub x-over 60 to 80 herts with a 24db slope
Mid x-over 80 to 100 herts with a 12, 18, or 24db slope.

As a general rule you want some gap between the sub and mid x-over points since you will have more speakers playing those freqs. That will give you a smoother responce curve, and alow some room when you fine tune everything.

Hi Jeremy, i have a set of 3 way Focal 165w3 and a 4 chanel promos 450 powering them, the amp has no xover. The midbass, you can hardly hear it. The midrange and tweeters over power the midbass.

Sory, it's a ppi 450 pro mos.

I think glass/kiki is out right now on a break...

So what does the rest of your set up look like?

Off the top of my head, it sounds like something is wrong. Maybe the polarity on one of the mids, or where you have everything installed. I would set the x-over on your amp to about 80 with a 12db slope to start, and go from there.

One more thing. I am guessing the mids are in the doors. Make sure you sound deadon the inside of the door, and close off all the openings in the interior peice of sheet metal. (any sound deadoning matt will ork for this) You could be getting some cancelation if it is still open.

Yes, they are in the doors and iv'e sound deaden them very well. Lets see, i have a Eclipse 5423 hu, 2 Audio Control EQTs, 2Audio Control over drive line drivers, 1 PPI FRX xover, i use it for my subs. The subs are Pioneer TS-W305DVC in a sealed box, powered by a PPI A1200 amp. Front doors i have Focal Utopia 165W3 speakers and a set of Focal Polyglass 165V both sets are 61/2. Kick panels i have 4'' canton midrange with tweeters in the middle of them. In the rear doors i have a pair of 61/2 Infinity speakers and a pair of 61/2 Diamond Audio M361 speakers. Two 8" midbass Drivers in truck speaker boxes, i don't know if i'm going to keep them or not just trying them out. Oh, i have 4 sets of focal tweeters up front and the 2 that are in the kicks, 2 sets of focal tweeters in the rear. And i have that PPI DCX-1000, thats all i can think of for now, lol..

Forgot, i have a PPI 450 pro mos for the Focals and a PPI a404 and a PPI a300 that i am using for the interiors. I have 2 PPi 2050am amps and a a100 here i'm not using at the moment:]

Steven, it sounds like your running into the same cancellation and phasing problems, we always try to warn people about. That many speakers, all at different path lengths is causing you all kinds of problems.

Think of it this way. Sound waves are an AC wave. When they arrive at your ear you want the waves from each speaker to be as close to the same polarity as possible. Thats why switching the polarity on one side can help center the soundstage (sometimes). Even with a simple two way component set, your never really going to get all the freqs to arrive in polarity with each other. Theres to many things for the waves to bounce off of, and the path lengths to your ear are to different.

Now let’s add in more speakers. Not only do you add in more AC waves arriving at your ears at different polarities, but now you have speakers sending out sound waves, canceling out other sound waves. (Any time a wave is met by a sound wave on the same freq but 180 deg opposite in polarity you will have cancellation.)

My suggestion, drop half of your speakers, and get (or build) one good 3 way or 2 way component set.

Or (granted this won't be near as good) You can make a few changes to what you have, and get it a little better.

First off, take the tweeters out of the dash. Focals hate being fired into the window. The A-Pillar is ok, but you will still need some tweaking.

Second, get a computer based RTA, and adjust each speakers polarity so they arrive at the mic in close to the same polarity. And adjust your EQs to give you a close to flat response curve.

Thanks again Jeremy, where do you get a computer based RTA? I was reading a post from Glasswolf about speaker imaging, he said to use a dash mat. What do you do, put a rug on the dash,lol.. Not trying to be funny:}