Wireing Help....

[drifter136]

I have an amp kit that has a 4ga power wire (about 17ft long) that goes to a distribution block that steps down to an 8ga. If the 4ga is long enough, i'm just going to hook that into the amp and forget about the steping down to 8ga...My real question is that the kit came with an 8ga ground. I've heard that the ground wire should be the same gauge as the power wire. Will I be OK with the 8ga or should I get a 4ga ground?

Next, I have some quality 16ga speaker wire left over from a home theater install. Will that guage be fine for a single sub that is bridged into an amp that is 360wrms (JBL P180.2) or should I get some 14-12ga?

Lastly, I know that the RCA's and power wire should be run on different sides of the car, but should the Remote wire be run with the RCA's or the Power wire?

[PaulD]

usually, you use the same size cable for ground as you do for power. 4 Ga is like 4 times bigger than 8 Ga.

16 Ga might be good for mid/tweets, it may be a little small for a sub

[sofast]

What he said

[drifter136]

Thanks guys,

Another question...is there a warm-up period after installing a new amp and sub? If so, how should it be done and for how long?

[DeleriousZ]

yes.. for new subs there is what's called a 'break in period' in other words.. don't pound the sub really hard until you've had it playing at medium volumes for a few weeks.. should say something about it in the paperwork that came with the sub

[drifter136]

OK, now I'm trying to decide whether to put the amp in the trunk (mounted to the sub box) or under the passenger's seat.

I like the idea of having the amp under the seat, but then I'd have to run really long speaker wire to the trunk. Would there be a problem with running speaker wire so long? My amp can take up to an 8ga speaker wire, so what guage would be the minimum for this length (about 10ft or so)?

If I mount it in the trunk, I don't have enough 4ga. Would there be any problems with going from 4ga to 8ga for the last 3ft or so?

Also, I'm still having trouble finding a place to run the power wire through the firewall. I haven't been able to find an existing hole (except on the driver's side where there is a large bundle of wires going through). I would like to go through the passenger side if possible, just nervous about drilling through the firewall.

If anyone has a 5th gen Accord and can tell me or post pics of where you ran the power wire would be great.

Sorry for so many questions...I want to do it DIY, but want to do it right. Thanks

[Geeko]

i would put the amp in the trunk- running the larger power you are using that distance will be okay, and if you find a way to route it under the car you don't have to drill through the firewall (not a hard thing though) if you mount the amp under your seat, you have to worry about it being kicked. also, there is less loss with longer runs of power wire then with longer runs of speaker wire, especially when you get into more powerful signals from the amp to the wire. put it in the trunk, and go buy enough 4ga wire to run directly from your fuse block or distrobution block to the amp. going from the larger to the smaller gauge of wire effectivly reduces the entire length of wire, and besides, it's better to have a single piece of wire (each break or joint in a length of wire increases resistance and reduces performance)

[slim720]

I heard in this thread that power wire and RCAs/remote should be run on opposite sides of the car... is that because you can get interference if you run them together? Because I've got one of those high pitch whirring sounds that gets higher as i press the gas and lower as i push down the clutch or brake. I've been told that this noise is because I have a bad ground, but I've sanded the shit out of my ground and it runs straight into the chassy. My RCAs and power run side by side... could this be the source of that noise?

[krstofer]

Originally Posted by slim720

I heard in this thread that power wire and RCAs/remote should be run on opposite sides of the car... is that because you can get interference if you run them together? Because I've got one of those high pitch whirring sounds that gets higher as i press the gas and lower as i push down the clutch or brake. I've been told that this noise is because I have a bad ground, but I've sanded the shit out of my ground and it runs straight into the chassy. My RCAs and power run side by side... could this be the source of that noise?

In my experience, the whirring is caused from a bad ground for the stereo. Used to get it with my first install. Haven't had it in a while.

[slim720]

Is there any way I can be absoltely sure that the sound is because of a bad ground? Like If I solder it to some large peice of block of steel or something? Cause I can't imagine that I could sand down anymore to get a better ground.

[krstofer]

You should Did you use the ground that was on the stock radio? That is the wire you should use for the stereo ground. If you can solder that together it would be good.

For your amp, if you sanded and bolted, it should be good. Just make sure the ground is well connected to the amp.

Have you had the sound since you did the install?

Krs

[PaulD]

Originally Posted by slim720

I heard in this thread that power wire and RCAs/remote should be run on opposite sides of the car... is that because you can get interference if you run them together? Because I've got one of those high pitch whirring sounds that gets higher as i press the gas and lower as i push down the clutch or brake. I've been told that this noise is because I have a bad ground, but I've sanded the shit out of my ground and it runs straight into the chassy. My RCAs and power run side by side... could this be the source of that noise?

It's a myth .... try using UTP (unsheilded twisted pair) RCA's and run them down the middle. The middle of the car tends to have less noise.

[Geeko]

Originally Posted by PaulD

It's a myth .... try using UTP (unsheilded twisted pair) RCA's and run them down the middle. The middle of the car tends to have less noise.

he's probably right, in my experiance wiring home theaters and studio/live work, i've had WAAY more noise from bad grounds, connections, and power sources... i've never really noticed any problems with ground + signal. doesn't mean i go out of my way to put them together, but i don't worry too much normally.

PaulD: any reason not to use STP (shielded twisted pair)? whadya think of a strand of RJ-45 running down the car? i would think that would work, although i couldn't say for sure...

[slim720]

well sanding aint helping.. could either of these thing be the culprit?... I braided and electrical taped ground wires together instead of crimping(comes up off chassy, then splits 3 ways to a crossover and 2 amps) . Also my power and ground cables are 8 guage wire but where the ground is braided together I had to cut off about 60% of each wire to get them to braid. Now I know you are all prolly laughing now like "nubmnuts, of course thats the problem". But I only ever pump about 300 watts out of my trunk (quality is enough for me, I dont need much volume) and 40% of an eight gage wire seems plenty thick to me to carry that little current... but what do ya'll think?

[PaulD]

when you look at the construction of a sheilded cable and apply the proper physics/ math to the problem you come to realize that the space between the conductor and shield (running the length of the cable) basically makes a coaxial cable a "noise antenna" in the audio frequency range