Got a new headunit recently, but had a question....

Well recently I got an Alpine CDM-7874 CD player headunit. I got it because I thought my stock AM/FM radio unit was going out on me (turned out it was actually my CD changer that was going bad, and NOT the radio...)

So anywho, I got the Alpine unit from and installed at Circuit City, they were offering free installation on it, so I couldn't pass it up. Since I was getting a headunit that had pre-outs on the back (2 sets actually, one being for subwoofer purposes specifically), I had them connect my amp to the headunit, so I get a better, cleaner signal to my amp to drive my sub I have. Something I'm noticing though, is everytime I turn on my radio, my sub pops really loud, unless I have my amp turned off which I can control via a switch I have my remote wire hooked to. Is there anyway I can prevent this from happening WITHOUT having to turn my amp off before I turn on my radio? I dunno if it may have anything to do with it (refering to how long it takes the amp to kick on vs. the pop the headunit seems to send through the pre-outs when it's turned on) but as I have it right now, my amp remote wire I have hooked to a blank terminal on my fuse box, that gives it power ANYTIME the key is in at least the ACC position. Would haveing the remote wire hooked the radio's power wire maybe prevent this, as I'm thinking that when I turn on my radio, the powering up of the amp will allow the "pop" to happen, before the amp is fully powered up, as it takes a second or 2 for that, where the pop happens as soon as I push a button to turn on the radio or CD player. Any thoughts, ideas, suggestions? I'm concerned, because I know this "pop" can't possibly be good for either the amp, or the sub especially.

i had that problem before. there is almost nothing you can do about it. you gotta turn on your headunit on before your amp. thats the best known way. some amps now have the "soft-turn on" output, which quiets the pop when you turn it on. you got a few choices to make now:

1. buy a new amp with that feature
2. try to shorten the ground cable
3. live with it.
4. turn on the headunit before the amp.

good luck.

That's why you shouldn't mess with the remote turn-on lead, so the HU must turn on first.

Where is your amp grounded? what about your headunit? somewhere you have what is called a ground loop. If your amp shares a somewhat common ground with an accessory, say your brakes everytime you hit your brakes you hear a popping noise in your sub. If your headunit and amp share the same ground path then that could be causing your popping. Try a different ground for either your radio or amp or both and let me know what happens.

- Brian

My radio I think uses the ground that's part of what the stock radio uses if I'm not mistaken, since they hook it to the same harness via an adapter harness. My amp I have grounded to one of the bolts that holds the outer tail light cluster to the body, in the trunk. I haven't yet had a problem with my amp ground location....

-My amp I have grounded to one of the bolts that holds the outer tail light cluster to the body, in the trunk.

Although one of the easiest way to ground an amp, probably the worst place you could choose. Try a seat bolt or seat belt bolt under your back seat. These bolts go straight through the cars frame and provide a better ground contact for the amp. Also use a star washer if youre not already. Also, is your amp mounted straight to metal? If the amps chassis is touching metal you can also create a popping problem. If it is resting on metal, insulate it, build an amp rack or take a piece of MDF cover it with carpet and mount your amp to that. When youre done smoke one for me.

- Brian:smoker2:

maybe its just circuit city... im thinking they dont know shit. a friend of mine had an amp & box hooked up by them, and he would always turn the volume all the way down, cause whenever he would turn the radio on, it would pop. i just thought it was cause they didnt put a fuse between the battery and the amp. i did my install myself, and i never had that problem. maybe i should work for circuitcity, and do it right for them.

while speaking of grounding I have a 00 integra where is a good place to ground I dont really care for where I have mine grounded now

Originally posted by EFsleeper
-My amp I have grounded to one of the bolts that holds the outer tail light cluster to the body, in the trunk.

Although one of the easiest way to ground an amp, probably the worst place you could choose. Try a seat bolt or seat belt bolt under your back seat. These bolts go straight through the cars frame and provide a better ground contact for the amp. Also use a star washer if youre not already. Also, is your amp mounted straight to metal? If the amps chassis is touching metal you can also create a popping problem. If it is resting on metal, insulate it, build an amp rack or take a piece of MDF cover it with carpet and mount your amp to that. When youre done smoke one for me.

- Brian:smoker2:

I can try that, but something tells me that won't help, relocating the ground wire. But I will try it out. :)

My amp I have mounted to a wood board that is mounted to the sheet metal of the bottom of the trunk, so the amp isn't touching anything metal itself.