1989 Town Car issues

**jscoobya** · 10-04-2007, 08:27 PM

Hello
Im new to the site. I have a few questions about moding my 1989 Town Car. I recently purchased a Dual XDM6820, a pair of 6 1/2" 200 watts three way Roadmaster speakers, a pair of 6"x9" 400 watts three way Road master speakers. When I went to install it all i noticed that my car was equiped with "Permium sound" so could not use half the wiring harness kit that bought. The speaker wiring harness was diffrent because it hooked up to a factory amp in the back, I could not figure out how to wire the new head with it so i ran all new 18G speaker wire. It all sounds good except when i turn it up to about 35-40 with alot of bass, I get this anoying high pitched sound that kind of sounds like a guitar wire vibrating, the sound is parallel to the pounding of the bass. I was wondering if anybody knew what could be cause'n it.
Now for my next question, I wanted to purchase 2 amps to place in the trunk along with some subs. But I cant figure out how to wire the Amps. I dont have the money to purchase the amps/subs atm since i recked my wives car(06 uplander). But i want to get the wiring done. I have an RCA cable that will conect to the Dual stero via the pre-amp output. my major issue atm is runing the big beefy power cable thru the firewall. How should I go about it? Or should i just run the power cable under the car, near the frame bars, then into the trunk?
Thank you for your time.

**envisionelec** · 10-05-2007, 09:41 AM

Originally Posted by jscoobya

Hello
Im new to the site. I have a few questions about moding my 1989 Town Car. I recently purchased a Dual XDM6820, a pair of 6 1/2" 200 watts three way Roadmaster speakers, a pair of 6"x9" 400 watts three way Road master speakers. When I went to install it all i noticed that my car was equiped with "Permium sound" so could not use half the wiring harness kit that bought. The speaker wiring harness was diffrent because it hooked up to a factory amp in the back, I could not figure out how to wire the new head with it so i ran all new 18G speaker wire. It all sounds good except when i turn it up to about 35-40 with alot of bass, I get this anoying high pitched sound that kind of sounds like a guitar wire vibrating, the sound is parallel to the pounding of the bass. I was wondering if anybody knew what could be cause'n it.

Yes, the 6x9s are picking up the vibrations of the subwoofers, sending a voltage into the sub amp's "speaker level input" (you didn't mention, but that's how it happens) via the speaker wires and coming back out the subs. It's basic feedback. You will need to either turn the sub amp down or use RCA cables into the sub amp.