Crossover help

kevinberry1 · Post by **kevinberry1** » Tue Mar 29, 2005 7:23 pm

I have installed my 6.5" components and am using an Audio Control 3xs crossover for my midrange and sub amps. I used seperate RCA's for the front and rear channels but when I hook up the RCA's for my midrange amp to the front/high channel I don't get any sound from the woofers, just the tweeters. I can get full range when I hook them up to the rear/high position, but I can no longer use the fade function on my head unit because everything is running on the rear channel. I have no problem with the low pass output for my subwoofer.
I was able to download the manual for my crossover, but it hasn't helped me figure out how to change the output. I know there are crossover modules that can be changed in the inside the 3xs, but am not sure what I should do. The crossover frequencies are 150 for the front, 90 for the rear, and 90 for the subwoofer crossover module.
Anyone know of what I should/could do to regain the ability to fade the sound output correctly?

William from NOLA · Post by **William from NOLA** » Tue Mar 29, 2005 8:34 pm

Did you buy it used?

What about setting the crossover to the lowest point with the high pass on for the front channel? Did you check all of the EQ settings (if any)?

Fishy · Post by **Fishy** » Tue Mar 29, 2005 10:49 pm

Thats weird.

Are you sure the front module is 150 Hz? You should still get a noticeable amount of midbass with that setting. As an experiement you could try swapping your front(150 Hz?) and rear(90 hz) modules. I've owned the 2XS and the 4XS, both of which were fairly simple and straightforward in their operation(set xover points and gain). If utilizing the 90 Hz module up front doesn't help then there may be something fubar'd in the front channel. If the swap works then get yourself another 90 Hz module for the rear or do like I did and make a few. They're just a bunch of resistors. There should be a formula in your manual to determine the proper values or you could simply measure the resistance across opposite pins on your existing 90 Hz guy.

-Fishy

kevinberry1 · Post by **kevinberry1** » Wed Mar 30, 2005 6:12 am

Thanks for your help fishy. I hadn't thought about switching the modules. If it works that will be great because I don't plan to run another amp for rear speakers. I'll try it tonight after I get home from work and let you know what happens.

Fishy · Post by **Fishy** » Wed Mar 30, 2005 8:39 am

Hmmm..... why do you need a fader then?

I'm pretty sure the lowpass on the 3xs is "non-fading" only(utilizes a non-defeatable summing amp) so you can't really use the fader as a subwoofer level control and still use the hipass. If you're powering your rear fill off the h/u you shouldn't lose any functionality there regardless of whether you're using the front or rear hipass. Just make sure you have both front and rear inputs hooked up to your h/u so the xover can sum them for that "constant bass" lowpass output. If you're stuck using thr rear hipass just connect the front h/u preouts to the 3xs's rear inputs and visa a versa.

lol, that make any sense?

:)

-Fishy

kevinberry1 · Post by **kevinberry1** » Wed Mar 30, 2005 9:42 am

I want to be able to fade from the front as a way to reduce the volume of the front speakers if need be. I was running my 6x9's off the deck, but decided to just unplug them for a while to see if I liked it.

Switching the RCA's didn't seem to make a difference, but I will try swapping those modules tonight. It seemed strange that the crossover could over ride the use of my RCA's and turn my front input into a rear output. I guess I don't know the mechanics of how the crossover could change that.

Fishy · Post by **Fishy** » Wed Mar 30, 2005 1:47 pm

What happens when you fade your front speakers?

Does your subwoofer output go down as well?

It shouldn't if you have both front and rear rca's hooked up to that 3xs. If all you need to do is attenuate your front speaks as needed you should be fine just utilizing the 3xs's "rear" hipass filter(the one thats working, right?). I suggested swapping the rca's just so that when your h/u "said" you were fading the front thats actually what you were doing and in case you were powering rear speakers off the h/u.

-Fishy

kevinberry1 · Post by **kevinberry1** » Wed Mar 30, 2005 9:01 pm

After inspecting the inner workings of my 3xs, I noticed that the previous owner had replaced the factory front module with a 4500 hrz module, hence my problem with just getting high frequencies. I swapped this one with the 90 hrz for the rear and all is good. Thanks for your help fishy. Now I can fade to the rear as a way to control the output from my components. If I can get my custom install done everything will be good to go.