What am I doing wrong?! Clearly the rear speakers aren't blown because the one single rear speaker that worked when I had all the speaker grounds connected in addition to the chassis ground sounded great. Unfortunately now for whatever reason, when the amp powers on and the rear speakers kick on, they sound like absolute ass. Then saw your comment, so I undid all the individual speaker grounds as you said it grounds thru the chassis ground, and doing this got sound to come out of all 4 speakers. This caused only the passenger side rear speaker to play sound, and the deck's balance/fader controls did nothing, BUT the sound quality was excellent.
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Wired up new head unit to the four positive speaker wires in the car harness, and then wired up the negatives, as well as chassis ground, power and switched power, power antenna and amp turn on wires I wired together to the blue/white on the new deck harness.
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Anyway, been trying to do this for hours now, finally stumbled across your long comment on the official e30 aftermarket radio install thread where you said the initial post didn't apply to late model premium sound cars. Had the original deck, unmolested otherwise as far as I could tell, was owned by an old woman. Factory amp I believe (there's a box behind the carpet on the driver side in the trunk behind the antenna actuator, assuming that's the amp?). The HU will lead a long happy life.Ĭlick to expand.Hey man, having issues installing an aftermarket deck in my 1990 325i coupe with premium sound. Running "+" to the amp and leaving "-" open is just fine. The amp is speaker level only.įinally, you do not need to 'load' the outputs from the HU. One thing it won't do is work correctly with preamp outputs, and that's the SECOND mistake that people make in upgrading HUs. It's appropriate for the installed speakers and will work very well with nearly any HU. There's NOTHING wrong with the stock amp. I won't be surprised if this is what the OP did. Well all this accomplishes is to short the HU amplifiers to ground, so you get nothing out of anything. One of the most common reasons why aftermarket installs don't work is that people seem compelled to do something, ANYTHING with those "-" outputs, so they tie them to ground in a mistaken attempt to make the output single-ended. The "-" outputs from the HU are cut back and left unconnected. Yes, they're speaker level drive, and that's what the amp expects. What you need to do with any recent HU is to use the four "+" outputs to drive the amp. It's changed to "floating" (differential) in the amp. The wiring from HU to trunk-mounted amp is ground-referenced. (There's another white wire that's bundled with the rest of the radio wires, that I don't have plugged into anything, photo below - aux. Red/ Brownish, Goldish, Greenish Color (pic below) -> "Memory Backup Lead" Purple/ Grey -> "Power Lead" (Accessory 12v) Grey/ Red -> Illumination (what exactly is this anyways)
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Yellow/ Brown (#1 - there's another one) -> Front Left. I change some of the setting and turned it off and on to make sure it was saving settings, and it is.īlue/ Brown (#1 - there's another one) -> Front Right. I increased the volume, turned the power on and off, but the same thing happened (same very faint audio). I get the faintest audio coming from all the speakers (i have to put my ear to the speaker to hear anything), which cuts out if I adjust the volume. Also, the new head unit works mechanically, I just don't really get sound. OK, so here's the latest the lights, etc.