Car Audio wiring question.

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Jovec

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Dont forget about the ground wire from amps/power block/fuse block. That is the most important thing not to forget because if you do you will get drive-train whine. You want that wire connected to bare sheetmetal somewhere. Even more preferably the underbody rails.


I plan to tie the amp's ground back into the factory wiring ground. Presumably it is ground correctly.
 

Lambourne

Ahn'Qiraj Raider
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If the only problem is the foam on the factory sub, I'd just have that one refoamed.

Factory tweeters will have crossovers on them already, no need to add new ones.
 

Xarpolis

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Also, never run your power cables parallel with your audio feed. They should cross at a +, and never run ||. A + cross of wires gives the power less chance to magnetically pull the electrons in the source material, thus distorting the sound (engine noise). The easiest way around this if you have to run the wires to the same place (and you do), is to have the RCA on one side of the car, where as the power runs down the other side.
 

Jovec

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Subwoofer and amp came.

Problem 1) Factory sub was 10", but the mounts are spaced more like a 12" sub. The cutout in the rear deck was essentially 10", but the factory sub had these extended tabs leading to the screw holes. I "made" some really large washers to provide clamping pressure for the replacement sub. The new sub does seem securely in place.

Problem 2) I was sent the wrong amp - a more powerful version than the one I ordered. I went with a smaller amp in hopes of reusing the factory power wiring. So I can either a) run new power line , b) send it back, or c) use the more powerful amp with the factory wiring, and if there is a problem the 30A fuse in the car fuse box should blow, at which time I will just have to run larger gauge power wire.
 

Xarpolis

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The issue with thinner wire and amps is heat. Thinner wire from a factory setup will heat up, where as proper wire/fuse will not. You would probably be better off buying a cheap wiring kit w/ fuse on amazon, then use that.
 

Lambourne

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Using factory power wire is fine as long as you don't change the fuse (it's rated to match the wire gauge used), if the fuse starts popping because you're drawing more power than before you can upgrade the power wire later on (and in the meantime, replace fuse and keep it turned down a bit)
 

Jovec

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I've had in all wired in for a week or so now with no problems. I think I should be fine on the factory power wiring (two 16 gauge lines fused together at 30A). If it blows, I can always run some new power line. The amp is only 60w RMS x 4 @ 4 ohms. The amp itself is fused at 25wx2 but keep in mind that rating needs to account for running a 2ohm load or bridging which will have a higher power output, and I am doing neither.

I am still trying out different configurations for the speakers. My first attempt I had one channel sent to the 3-way crossover for the sub, front mids, and front tweeters. The second channel I set the (fixed) high pass filter on the amp at 80Hz to the 2-way crossover, going to the rear mids and bridged to the single center dash speaker. This resulted in the center speaker's volume output too high compared to the rest and the 4 door speakers not having quite enough lows and highs. Still overall it sounded okay.

Today I changed things around slightly, bypassing the two-way crossover for the rear mids and using the amps variable high-pass filter set to around 100Hz. I also disconnected the center dash speaker. This produced a fuller sound from the rear mids. I might try wiring the 4 door speakers in series off of one amp channel so they all get the fuller sound and then use the second amp channel with a crossover for the sub and tweeters. The best solution is to have more amp channels - whether through a single amp or multiple amps - which I might do if I ever run higher gauge power.

Edit: Wired the 4 door speakers in series. They are connected to amp channel A which has a variable high pass filter, so they sound better with the HPF set around 100Hz or so instead of the ~1.2KHz to 4K frequency range they were getting off of the crossover. The sub and tweeters are on channel B which I have running through the 3 way cross. There is an obvious volume difference between the channels but being that it is only bass/highs it doesn't sound too bad. I could correct this via a fader but I am only running one input channel to the amp, so no fading. In order to make use of a second input channel for F/R fading, I have to piggy back on the center channel speakers along with another pair of unused wires (since I have no RCA cables run). I just need to solder on more RCA jacks which isn't too had to do. I am going to leave it like for a week and see how it sounds. The center dash speaker is unused - it seems like a waste but I have no way to get it a decent range of sound. The mid output on the 3 way cross are currently unused and I could bridge the center channel across those, but then I will have more volume issues and the mid outs are like 1k-4k frequency only.
 
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Void

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This isn't really the place for it, but then again I couldn't think of anywhere else since it didn't exactly rustle my jimmies. Made me laugh at what a retard my coworker is though.

He's rebuilding an old Firebird, and has done a ton of work on the interior. From the pictures it looks pretty good (please note, there's no chance in Hell I'm going to this guy's house, if I do I'll be called over there for every possible reason. He already texts me too much, and I literally despise him). He wanted to put a nice stereo in it so I gave him some advice on what to grab in his price range and how to run the wires (power away from speaker wires, etc.). So for some reason this weekend he got a bug up his butt to put it in and just hear it.

So he sends me a pic of the wiring diagram that he found on the internet somewhere, and asks if that is all correct. I say sure, in general. I mean, it literally has a generic drawing of a battery, an amp, and a head unit, with the power, ground, and aux power/remote lines. Speakers are separate, which is fine. I tell him that he doesn't need to run the ground back to the negative terminal on the battery, he can just find a good screw on the frame near each of the amp and the head unit, sand off any paint, and attach it there so he doesn't have these long ground wires all over.

It's not working, so first thing I ask is if he setup the aux/remote lines properly. The reason this was a huge first question for me is because he used to have a boat, and he would talk about how he had to disconnect the power line from the battery to turn off the stereo in his boat, otherwise it stayed on and drained the battery. I could have told him how to fix that, of course, but remember I despise him, and he didn't ask. He sold the boat years ago though. But I figure he probably doesn't know shit about that still. He says he's bypassing the ignition switch right now because he just wants to hear it for a minute. Ok, whatever, so I just ensure that he actually does have a separate wire attached from the battery to the proper terminal at least.

Still not working. I spend way too much time over texts trying to trouble-shoot shit that I shouldn't even have to ask about. Then he says he feels like I led him astray by not having him connect everything to the negative terminal of the battery, he doesn't feel as if he's "completing the circuit" by just connecting everything to the frame. I say, well, the battery is just connected to the fucking frame of your car anyway, right? He says no. I'm like, what the fuck are you talking about? Show me. So this is what he sends.

PART_1541381496264_IMG_0204.jpg

Understandably, I ask him what the fuck I'm looking at, where is the battery? He says he has no battery, because he has no engine in the car or anywhere to even put a battery (nor does he actually have a battery at this point), so he's just hooking it all up to a battery charger. What. The. Fuck.

Before I can pick my jaw up, he texts that he tried hooking everything to the negative end of the charger, and it still doesn't work, and he's about ready to throw the whole thing away, he's so frustrated. So against my better judgment I tell him not to throw it all away, that of course it isn't going to work because a charger doesn't output the same power rating as a fucking battery AND the charger is grounded through the wall outlet, not the car, so of course it didn't work previously either. Just buy a fucking battery, charge it up with the charger, and plop it down on the ground right where he had set up the fucking charger in his picture.

Blew my fucking mind. I mean, I get that people don't always understand electronics or other shit that seems easy to other people, but this was absolutely retarded. What does he intend to do anyway? Sit in his car with no battery or engine, in his garage, up on blocks, and rock out to tunes??

This is the same guy that a coworker and I have a running joke about that the first time he fires up the engine he's rebuilding for that car, it will probably throw a rod through his skull, miss his tiny brain, and he'll get famous on TV for being alive with an engine part through his skull.

EDIT: Oh, I forgot to add. This is where Monster makes their money. I repeatedly told him not to buy Monster or any other "premium" cables. He did anyway, because the guy at Best Buy told him it was on sale for a really great price, and if he's putting all this work into restoring a car, he's going to be upset when he has to redo all the wiring later because it doesn't sound as good as it could. I laughed and asked him why he only spent $200 on the fucking head unit then, and less on the amp I believe, if he's so concerned about "premium sound."
 
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Xarpolis

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Your co-worker not-friend is a fucking idiot. I'm talking about the entire story, and not just the wiring at the end. Fucking idiot. He should be euthanized.
 
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