legacycentral bbs

My amplifier stays on for about a second after the head unit turns off. This has nothing to do with my previous problem, it has something to do with the head unit telling the amp to shut off too late before it cuts off its own power, and the amp's soft shut down circuit taking too long.

So the result is, head unit shuts off, amp stays on for a second and attempts to amplify a null signal from the head unit which causes the midwoofers to go "pop". Its annoying to say the least, and if gone unchecked can damage the speakers.

So I need a circuit that will tell the amp to turn off when I turn the key. Stinger makes a unit that connects to 12V constant and ACC, and the remote turn on wire, but its ~$20 and I bet its pretty simple to do. Any help?

Thanks.

Hmm, well, your accessory rail stays powered when you shut the key off though, right? So you can't use that as a signal for when you shut off the ignition...

How would you feel about your amp being powered only if the ignition was in the ON position? You could just stick a relay inline with the remote wire (cut the remote wire and connect it to terminals 30 and 87) and power it off the ignition circuit (ground terminal 85 and connect 86 to an ignition-switched source).

I don't think it matters that the ACC is still powered after the car shuts off. Its just a delay after I turn the key, so it should perform the same. When the power signal is cut, it tells the amp to shut off instead of waiting for the head unit to tell it to.

Okay, then try what I said but using the ACC line instead of the IGN line.

Cut the remote wire, connect the stereo side to the 30 terminal, connect the amp side to the 87 terminal. Connect the 85 terminal to ground, and the 86 terminal to the accessory power wire.

See if that gives you the results you want.