Need help Setting X-over on amp!!!!

Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=7775
Printed Date: May 10, 2025 at 9:29 AM

Topic: Need help Setting X-over on amp!!!!

Posted By: Wantofok
Subject: Need help Setting X-over on amp!!!!
Date Posted: January 07, 2003 at 4:48 AM

Hy, I need some help on how to configure the xover settings on my amplifiers to get the best SQ possible. I'm a bit confused to be honest posted_image

Ok this is what my system consists of:

Rockford Fosgate 500a2(2 channel) which is running on one channel bridged with 1 Polk Momo 12" sub.

Phoenix Gold T400.4(4 channel) which is running a set of 5 1/4 boston rally components up front(front channels). A pair of 6 1/2 polk dx's in the rear(rear channels), but I also have an infinity 605cs system laying around that I might replace it with, please advice. All in factory locations.

I also have an Alpine ere-g180 eq setup for both the amps signals.
My car is a 2 door acura integra by the way. Will appreciate any help. Thanks, Jeff.

Replies:

Posted By: F4Pilot
Date Posted: January 07, 2003 at 10:07 AM

Initially, use your adjustable crossover on your eq to split the usable signals to your sub and your highs. If your eq's crossover is on-off selectable, you can just use the amp's onboard crossovers. Actual crossover points vary according to taste and listening volumes. Hi bass volumes usually require a lower crossover point. You will want to gap the hi-pass xover point a little so as to not make the hi's work so hard.

In either case: try setting the sub around 80hz, and for the highs set xover point around 125-150hz at the amp if not selectable at the eq. Also use your individual frequency points on the eq to help tailor the sound. Whatever the "correct" settings are, the goal is to eliminate distortion at the hi-end of the sub and at the low-end of the highs.

Posted By: Wantofok
Date Posted: January 08, 2003 at 1:03 AM

Alright sounds pretty straight forward, thanks for the feedback posted_image

. I still have one more problem though, When stereo is at about 50% volume sound starts clipping. The readable gauge on the eq is all the way up in the red at about 30% volume. This shouldn't be happening, my guess is that I am overpowering my amp. This is only for the 4 channel amp. Please give some feedback, thanks.

Posted By: F4Pilot
Date Posted: January 08, 2003 at 12:13 PM

Clipping as in, past the point of human audible distortion and the sound starts cutting out? Your amplifier gains maybe set too high. Also make sure there arent any user selectable boosts on the rear of the eq that could be causing this. What type of head unit are you running?

You say that this is only a problem with the t400? how do you know? you adjusted the crossover points individually by connecting only one amp output from the eq at a time? you are sure the sub is not distorting?

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02 Odyssey / 99 F4

Posted By: Wantofok
Date Posted: January 08, 2003 at 3:38 PM

Ok, the amp gains on the t400 are set on lowest. Well, actually, it's labeled sensitivity but still I have it set on lowest signal level. I'm using a stock head unit with a h/l converter and an Audio Control Overdrive which is set at 10db. I know that it's the t400 causing the clipping because the eq has on on/off selection for the sub. So I'm sure the sub isn't distorting. Please help me out here!! posted_image

Posted By: F4Pilot
Date Posted: January 08, 2003 at 8:58 PM

Sounds like you have gain set too high somewhere else as you didnt mention these other electrical components previously. The sub is most likely distorting as well - but not to the extent that you can hear on the highs. But if you say its not.......

Assuming the h/l converter wiring is correct, check for output gains. Set them at the just-above-minimum setting. Also, goto your balanced output processor and turn the gain down there as well.

You will need to turn down all the gains everywhere to just-above-minimum and start tuning your system from there. If you turn one or more gains down too much than you may not hear anything.

Be careful with any signal processors. They help tremendously with sound quality but can also overdo it - as what appears to be your problem. Try not to have any one component on full gain and remember that too high of a boost on your inputs will clip and spike faster than you can say FRIED chicken.

Good Luck.

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02 Odyssey / 99 F4