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Grot
09-04-2010, 02:27 AM
im finally going to instal my sub in my truck. What all do i need to wire it?

Its a single sub, with dual power imputs and a single channel amp.

alltracNyx
09-04-2010, 02:40 AM
RCAs
Amp kit
Speaker wire

A set of two channel RCAs, a 4 gauge amp install kit (some come with RCAs, some don't), and some speaker wire. The amp kits come with 17' of 4 gauge wire for power, 17' of 20 gauge for a remote wire, like 4' of 4 gauge for a ground, a fuse holder, fuse, and some ring terminals. If you have some of these things already, or can buy it cheaper separately, like buying wire by the foot (as opposed to precut in the package), go for it. A thicker gauge speaker wire for the amp output to the sub is recommended. Rather than the typical 20 gauge speaker wire, use something like 16 or 12 gauge, depending on how much power your sub is pushing.

Grot
09-04-2010, 03:25 AM
I have this sub

http://www.crutchfield.com/p_575RFP4212/Rockford-Fosgate-HE2-RFP4212.html?search=rfp4212&tp=111

and this amp

http://www.crutchfield.com/p_236TH250D/MTX-Thunder-Class-D-Mono-Subwoofer-Amps.html?search=mtx+thunder250d&tp=14

Plan on putting it in this box

http://www.crutchfield.com/p_777BB1212S/Sound-Ordnance-Bass-Bunker.html?tp=127

---------- Post added at 01:53 AM ---------- Previous post was at 01:51 AM ----------

What is the Second RCA for?

I know the first one is the imput to the amp, the second goes to the output on the amp, but where does the other end go?

I understand electricity, but not audio.

---------- Post added at 02:25 AM ---------- Previous post was at 01:53 AM ----------

Would this amp kit work?

http://www.amazon.com/Power-Acoustik-AKIT-8-Amplifier-Speaker/dp/B003CYL7IA/ref=sr_1_10?ie=UTF8&s=electronics&qid=1283567062&sr=8-10

Murgatroy
09-04-2010, 08:26 AM
I can help you. It is all child's play to me. It would be easier to do in person.

---------- Post added at 03:26 AM ---------- Previous post was at 01:57 AM ----------

Ah, what the hell, I just had a long reply typed out... Here are the cliffs.

The Amp kit is too small. Go bigger, I prefer 0ga.

The amp will be fine for that sub. The extra set of RCAs is an output so you can daisy chain multiple amps.

The sub is a DVC. Meaning you can run it at either 2 ohm single channel, 4 ohm on two channels or 8 ohm on a single.

You want 2 ohm as you amp can handle that. Most amps are 2 ohm stable.

Wire the sub red to red, black to black internal. Run one set of wires from the posts to the box terminal red to red, black to black. Run the amp to the box, red to red, black to black.

Is that box gonna be small enough to install in a single cab Ranger?

Facime
09-04-2010, 08:47 AM
Murg, 0ga is WAY overkill for a 125w mono amp. 8ga is MORE than enough to go engine to cab in a truck.

Murgatroy
09-04-2010, 09:34 AM
Murg, 0ga is WAY overkill for a 125w mono amp. 8ga is MORE than enough to go engine to cab in a truck.

I would be more comfortable at 0ga than 8ga. While 8ga may be enough, if he ever upgrades to a bigger amp, it will have to be replaced.

He hasn't been bit by the bug yet. Odds are good it will get him. When it does, rather than have to pull all the wire and start over, if he buys once, he cries once.

0ga would mean he would be good for nearly anything he wanted to put in his truck.

david in germany
09-04-2010, 09:36 AM
For that amp and sub combo this would be the perfect kit for you. http://www.knukonceptz.com/productDetail.cfm?prodID=KFX-AK8
If you EVER plan on getting a bigger amp, this one would be better.
http://www.knukonceptz.com/productDetail.cfm?prodID=KOL-AK4

0ga is WAY overkill for this setup though.

Murgatroy
09-04-2010, 09:40 AM
Your links fail.

And for the record, I will help install anything, it doesn't have to be 0ga.

Even though I have 0ga in Chaos, and no system.

david in germany
09-04-2010, 10:40 AM
Your links fail.

And for the record, I will help install anything, it doesn't have to be 0ga.

Even though I have 0ga in Chaos, and no system.
Even though you are using 0, your still #1 to me. :)

Grot
09-04-2010, 11:25 AM
Thanks for all the replies. and i appreciate the offer to help murg.

Its going in my passenger floorboard. thats the only place i can fit it.

And i was thinking of installing it with some quick disconnects inline so i can move it if anyone rides with me.

---------- Post added at 10:25 AM ---------- Previous post was at 10:19 AM ----------

This amp kit work? its 4 gauge and a whole lot cheaper.

http://www.amazon.com/Legacy-LAMP4-Gauge-Amplifier-Installation/dp/B0013C22AU/ref=sr_1_1?ie=UTF8&s=electronics&qid=1283595814&sr=8-1

---------- Post added at 10:25 AM ---------- Previous post was at 10:25 AM ----------

This amp kit work? its 4 gauge and a whole lot cheaper.

http://www.amazon.com/Legacy-LAMP4-Gauge-Amplifier-Installation/dp/B0013C22AU/ref=sr_1_1?ie=UTF8&s=electronics&qid=1283595814&sr=8-1

Maruki-kun
09-04-2010, 01:22 PM
8 gauge can support a LOT of power.

I'd go with 4 gauge because it's a good compromise.


also murg, he'd need A reducer for a 0 gauge to fit the am, plus ring terminals for a 0 gauge, plus finding a good spot to run a 0 gauge in a truck is a pita. ask me how I know.

Facime
09-04-2010, 07:02 PM
Also, unless hes going to be putting the system into competitions (not with a fosgate sub run by an MTX amp ;) ) The amp isnt going to pulling max power all the time. The battery to amp run is probably only going to be 6ft. Fosgate has a niftey little calculator (http://www.rockfordfosgate.com/rftech/wire_calculator.asp) you can plug in all your specifics of your equipment and it will recommend a wire size.

I agree that 4ga might be a goog compromise and allow for expansion down the road.


and here is an easy to read chart (http://www.the12volt.com/info/recwirsz.asp)

Grot
09-04-2010, 07:34 PM
I went ahead and bought the second wiring kit i linked. if it doesnt sound good, i will rewire it. no big deal...

alltracNyx
09-05-2010, 01:57 AM
I agree with Murg. 0ga ftw. It's what I have. But I am also running quite a bit more than Grot. He may get bit by the bug, and he may not, but 4ga is still rated pretty high as well. I think he'd still be able to upgrade from what he has and keep the 4ga.

However, not all 4ga was created equal. Sometimes companies will add more insulation and less actual wire inside the insulation to make it look like 4ga, but it really isn't. I would compare it to another (reputable) brand, side by side, and see how much wire is in the insulation in comparison. We had plenty of people bring in their own wires when I was still installing at a shop, as opposed to buying ours because it was more expensive, but you could definitely tell the difference.

I didn't mean that you needed two sets of RCAs, I was just saying that you need a pair of two channel RCAs, and sometimes they come in the amp kit that you buy, and sometimes you have to buy them separately.

Crutchfield has excellent wiring diagrams to help you understand if you're a visual person. Of course, this diagram shows a 4 channel amp for the interior speakers and a capacitor, but of which you can ignore for your installation.

http://i878.photobucket.com/albums/ab343/alltracNyx/CAandE/amp_wiring_diagram.jpg

But the patch cables listed are the RCAs that connect to the subwoofer preouts on the back of the radio and run to the inputs on the amp. And then there are speaker wires that run from the speaker outputs on the amp to the sub, wired the way Murg explained above.

Grot
09-05-2010, 02:04 AM
Thats easy to run then.

any issues grounding straight to the Chassis?

Murgatroy
09-05-2010, 02:53 AM
No. You want your ground as short as possible.

Think seat bracket.

david in germany
09-05-2010, 09:09 AM
However, not all 4ga was created equal. Sometimes companies will add more insulation and less actual wire inside the insulation to make it look like 4ga, but it really isn't. I would compare it to another (reputable) brand, side by side, and see how much wire is in the insulation in comparison.

QFT!!! Write up I did a couple of years ago.
http://www.celicatech.com/forums/showthread.php?t=17240

alltracNyx
09-05-2010, 06:46 PM
Haha, I never saw that thread, but it's definitely true. Funny that we used the exact same phrase. But there should be a better industry standard for wire gauge.

david in germany
09-05-2010, 07:19 PM
Great minds. :P

Grot
09-15-2010, 11:04 PM
Ok, so i have everything needed to install.

Just waiting to see how my vehicle situation plays out.

2 last questions.

Any specific Screws to hold sub in box?

Is Stuffing in the sub box necessary? I assume its an interior space thing, trying to take up extra space.

The box i got is 1.27 cft the Manufacturer recomends 1.25 cft in a sealed box.

Also, wiring a dual voice coil sub in parallel, will that create a 2 ohm load on the amp?

Facime
09-16-2010, 12:46 AM
Any specific Screws to hold sub in box?
Not really, I like to use drywall screws since I have boatloads of them handy.

Is Stuffing in the sub box necessary? I assume its an interior space thing, trying to take up extra space.
If you are talking about stuffing with polyfill, its the opposite of what you are thinking. Stuffing the inside of the box slows the pressure wave down a little and can make a smaller box effectivly larger. Since the box you have is already on the large side you dont want to stuff it.

Also, wiring a dual voice coil sub in parallel, will that create a 2 ohm load on the amp?
Yes

Grot
09-16-2010, 01:29 AM
Thanks for the clarification.

Okctrd
09-18-2010, 05:25 AM
did your amp kit include the fuse? if not you need one.

Grot
09-18-2010, 05:48 AM
Yes it came with a 40 amp online fuse. And the amp itself has 2 20 amp fuses as well.

Okctrd
09-18-2010, 06:06 AM
alright, i guess all you need know is to install it haha.

Grot
09-18-2010, 02:45 PM
Yep. I'm just waitin to see how my vehicle situation is. It will be installed next week more than likely.

Grot
09-19-2010, 06:10 AM
Lookng at the back of my headunit, all I have as far as RCAs go are audio out front and audio out rear. But in the menu on the radio itself it has sub level controls. Which set would I use?

Facime
09-19-2010, 08:26 PM
generally there is an options switch in the menu that lets you set the rear out to sub out, and quite often a crossiver point and other tweakable settings.


so in less words: rear out to sub

alltracNyx
09-20-2010, 12:35 AM
^Agreed. Most radios have a rear/sub selectable output. But you have to change the settings on the radio, otherwise the output to the sub will be incorrect.

Grot
09-20-2010, 12:49 AM
I will look into it to see how to do it on mine.

---------- Post added at 11:49 PM ---------- Previous post was at 11:48 PM ----------

its a sony CDX-GT300 if it makes any difference.

alltracNyx
09-23-2010, 11:36 PM
I believe the radio should be turned off, and then you either hold in the volume button or the source button until a menu pops up. Then use the volume button to scroll through the menu and look for the option. I think you then use the arrow keys (previous or next track buttons) to change the setting.

I could be wrong though, it's been a few years since I've dealt with anything Sony.

Grot
09-24-2010, 12:57 AM
Update: Old radio wont fit in buick.

Want to put a sub in with factory radio.

Going to put in a Line Out Connector on my 6x9 (used as bass only) and run it that way till i can rewire and replace all the components.

---------- Post added at 11:57 PM ---------- Previous post was at 11:55 PM ----------

EDIT: If i use these connectors, do i need to put them before the factory amp or will it work if i put them after the amp.

Basically i want to know if you can use an amped signal for a sub preamp.

alltracNyx
09-24-2010, 07:08 PM
You can hook these up after the amp, at the speaker level output wires going directly into the rear speakers. It makes the install easier, as you have less wires to run, and you can use shorter RCA cables if you like.

There are arguments in favor and against both hooking up the LOC before the factory amp, or after. On some newer vehicles (mainly Chrysler), some have argued/complained that the output to the LOC (and ultimately to your amp) is significantly decreased because the signal is overprocessed. However, on an older Buick with a factory amp (or GM in general), grabbing the signal after the amp works fine.

Also, when hooking up your connections, make sure that you have the correct + and - connections for the speaker wires. If you have one speaker connection out of phase at the LOC, and are running two subs, the subs will be hitting out of phase, thus cancelling each other out. It'll seem as though your subs aren't working. And make sure that you adjust the signal levels on the LOC itself, if too low, your subs will not put out much sound, if too high, you will get distortion.

Sorry if the info is overkill, I just don't know how much you know. Let us know how it sounds ;)

Grot
09-24-2010, 07:43 PM
overkill is good in this situation. i like to learn as much as possible. the LOC shipped today. prob get here monday.

Grot
09-28-2010, 06:45 PM
LOC should be here today.

I have one last wiring question.

Where will i hook up the REMOTE wire?

alltracNyx
09-28-2010, 07:09 PM
The remote wire can be hooked up to any 12v switched source, so that the amp only gets power when the car is on.

If you want to be lazy, I believe the yellow wire in the radio harness is the 12v switched wire. This however, will power the amp on, even if the radio is not on. You should not get any sound to the subs with the radio off, unless you are getting some type of feedback, or have a ground issue.

Since you have a factory amplified system, there should be a 12v switched wire that gets power only when you have the radio on. This would be the ideal equivalent to what you would connect to on an aftermarket radio.

Oh, and you could have made the aftermarket radio fit into the dash on this, but it would have required a little customizing. This is one of those cars where there just isn't enough room behind the radio to fit it in without additional work. Again, keep me posted, hope you get to hear your sounds soon.

Grot
09-28-2010, 07:23 PM
Yeah, i was told i could make it fit. but just dont have time to do it right now.

I will try to find my wiring diagrams to find that wire.

Murgatroy
09-28-2010, 07:35 PM
Yeah, but you lose the nifty steering wheel controls.

That is the biggest reason I never put an aftermarket HU in the Buick, the Monsoon System was decent enough for me.

Murgatroy
09-28-2010, 07:35 PM
Yeah, but you lose the nifty steering wheel controls.

That is the biggest reason I never put an aftermarket HU in the Buick, the Monsoon System was decent enough for me.

Grot
09-28-2010, 09:47 PM
Ya, i blew the rear 6x9s already.

I can buy a converter for the steering controls... for $70.

---------- Post added at 08:47 PM ---------- Previous post was at 08:41 PM ----------

Well apperently GM screwed me with a remote lead on the amp. It auto turns on when sound is detected.

My amp has something called SmartEngage. it says if you use the speaker level input on this unit and tie the front L+ and L- speaker leads from a source unit with BTL outputs (most high powered radios) the amplifier will turn on whenever there radio is turned on, allowing for easy factory head unit integration.

Or would it be possible to run a manually switched 12v power wire from somewhere to have an on/off switch in the cabin near me. Would that work in place of a Remote lead?

Grot
09-29-2010, 01:33 AM
Well i give up.

Went out and got an inline fuse and a switch for the remote line. Was wiring that in and all of a sudden i was smelling burning electronics.

I have everything unhooked. I dont know where i went wrong.


Murg if you have a free night sometime this week think you might be able to give me a hand and see if we can get this thing figured out?

Also, what is the third prong for on a 2 position switch? Ground?

And i dont have a multimeter to find a constant 12v to hook my remote to.

Murgatroy
09-29-2010, 02:10 AM
There is never a ground on a switch unless it is illuminated.

A two position switch has one power in, two power outs. Meaning you run nothing but hot through it. No ground. If you used a ground to a switch as well as hot, that is what cooked your wiring.

Let me specify. A switch is nothing but a door. If the door is open, you can go through (switch closed, power goes through) if the door is closed, you can not go through (switch open, no power through.)

That means you can run a switch on either ground or hot, normally hot since a 12v DC circuit will have a common ground, the chassis. The switch interrupts or completes the circuit. So in that sense, there is not hot or ground.

However a switch must be run in line completely either hot or ground, not both, unless, like mentioned above, it is an illuminated switch.

Otherwise the switch becomes a short, and bad things can happen with a short.

Grot
09-29-2010, 02:14 AM
It has an LED in it, but i only had on end hooked up: to the amp. and no ground hooked up to the switch, was just curious what the 3rd prong was for.

Murgatroy
09-29-2010, 02:31 AM
....|........|..........|
Power Ground Accessory

Grot
10-02-2010, 11:03 PM
Well after some wiring issues, i went back and fixed them. And i think this setup is gonna work... Right after i get another Amp.

This one was visibly smoking out of the case. Im assuming thats a bad thing.

---------- Post added at 10:03 PM ---------- Previous post was at 10:01 PM ----------

If anyone has a Cheap amp up to 400 Watts RMS i will buy it. i just want this thing to work now.