I'm just a car audio hobbyist but have been doing work for a few years now. I recently installed a rather large (1600watts) amp in a 2001 Mustang. It had a factory in dash changer and the "premium" Mach sound setup. I ran the high inputs from the plug that goes to the two 6x8's in the back dash (BLACK/ white and BLACK/ green pairs). When the gain was up on the amp if you closed the trunk it would cause the speakers to hum. The closer the trunk came to shutting, the louder the hum got. Disconnecting the plug to the 6x8's solved the problem. I was wondering what was the cause of the problem and a better way to fix it. Thank you.
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-=Shannon Tappan=-
Let me try and understand the situation better. You still have the Mach 460 set up in there. You spliced into the rear outputs of the speakers on the back of the head unit. And you are using high inputs on the amp and not rca’s. Now I take it the 1600 watt amp is for subs. Please let me know if this is how you have things set up and correct me if im wrong.
we have had this problem before.. usually grounding the input shield or (if your using one) the line out converter will take care of it.. it's nothing new.. some cars do it, some cars don't.. I don't know exactly what causes it..
I believe you are only getting this when you are using the factory radio and you actually turn the radio off and leave the key on.. amp hooked up on ign.. am I right? I don't know what causes it, but ground the shields and try that.... I will talk to my tech tomorrow and see what I can find..
Don't knwo what the trunk has to do with it.. 12volt, any ideas?
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George
David's Car Stereo
Baton Rouge, LA
You may have to run a ground strap from the trunk lid to body.....Just a thought....
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Clean tools = Clean work!
Are you using a High/Low converter or your Amps High input terminals? If you are using the Hi/Low adapter where is it located?
Well, I think it was getting feedback from the signal from the 6x8's in the back dash. The subwoofers have 200oz magnets and the trunk is rather small in those cars. I think the large magnets were causing feedback through the 6x8's and back into the amp. It normally would not have been a problem but the amp in that car never turns itself off. It won't turn on without the remote wire but even after you disconnect the remote wire it stays on. The cap in that car (Power Acoustik model PC1.2F) turns itself on and off automatically. So I figured that might have something to do with it but I think it may just be a bad amp from the factory (it was new). Anyways, I think when you closed the trunk all that metal got too much of the magnetic field from the woofers and because the 6x8's were close enough to be affected it sent feedback. That's my guess.
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-=Shannon Tappan=-