Wiring Gauge Suggestions

[Merciless 10+ year member]

Hi,

I have a 5 channel Alpine Amp. I am going with a component speaker system up front (probably Polk DB 5251) and have a sub for my trunk.

I want to bridge Channels 1-4, so I can send 120w to each of my components. What gauge speaker wire should be sufficient to handle 120w RMS (240w Max)? I am running the wire from the amp in my trunk (so ~15 ft.) and my components also have a crossover if that matters. I was thinking 14AWG.

I am going to send Channel #5's 150w to my sub (JL W1 10"). The sub is also going to be in the trunk (so less than 5 ft.). What gauge wire should I run for 150w RMS (300w Max)? I was thinking 10AWG.

The amp is a MRV-353, and has two 25A fuses. Total RMS power is 390w, total max is 780w. The amp is going to be ~25 ft. from the battery (~15 ft. straight line distance). What gauge wire do I need to support that power? I was thinking 8AWG.

Do I need a fuse next to the battery? If so, what Amperage would you recommend?

Is there anything else I will need for the install?

I have a HU, an amp, speakers, and a sub.

I know I need an -

adapter to fit my HU to my car

speaker wiring

sub wiring

amp power wire

amp ground wire

amp remote start wire

RCA's from HU to amp

Is there anything I am missing?

Thanks so much!

Ben

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[PlumbBill 10+ year member]

Let's start off with powering that amp.

YES you need a fuse at the battery, not to protect the amp, but to protect the wire & your vehicle.

Without looking up the specs of that amp the simple rule is the fuse at the battery needs to be equal to the sum of all fuses on the amp.

In your case a 50 amp fuse (2x25).

If you are running 50 amps @ 25 feet you will need a bigger wire than 8 awg.

8 awg is rated for more than 50 amps at a short distance.

You need to find what the amp is drawing, to find what gauge would be acceptable.

@ 25' 8 awg up to 20 amps, 6 awg up to 35 amps, 4 awg up to 50 amps, 2 awg to 65 amps & 0 awg for 125 amps.

That info is from IASCA & yes they do oversize a bit.

NEC code rates 8 awg @ 70 amps-- 70 degrees THWN.

 

[keep_hope_alive Premium Member]

I fuse 8 awg wire at 60A

I fuse 4 awg at 125A

the IASCA tables aren't for fuses, but for wire sizing based on minimizing voltage drop for DC current vs. distance.

NEC rates wire ampacity based on the terminal connection (based on temperature). connections are the weak link to wire ampacity - that is where heat is generated. the 60 deg C. column is more useful, but car audio wire isn't THHN/THWN, nor made for AC voltage/current. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[keep_hope_alive Premium Member]

Ben,

you will need ring terminals for the ground wire connections (and a drill/bolt to ground the ring terminal). you'll need battery adapters and terminals to connect the power wire to battery. i protect all wiring (especially in the engine bay) with split loom tubing - same stuff already in the engine bay to protect wiring. i also have plenty of zip ties.

i would use 8 AWG power wire fused for 60A with that amp, and 8 awg ground wire.

14 AWG wire is fine for speakers (and even 16 AWG or 18 AWG is fine).

10 AWG is fine for the sub, but overkill. the tinsel leads on the sub are much smaller than that.

you size wire for voltage drop (ampacity doesn't matter here). larger is better, but too large is difficult to work with and terminate. the connections made to the speaker/sub are the most important.

here are some build logs to give you ideas

http://www.caraudio.com/forums/car-audio-build-logs-cars-trucks-suvs/533022-2006-hundai-elantra-gt-5-door-simple-alpine-system.html

http://www.caraudio.com/forums/car-audio-build-logs-cars-trucks-suvs/516096-2005-scion-tc-sq-hertz-audison-pioneer-build-log.html

http://www.caraudio.com/forums/car-audio-build-logs-cars-trucks-suvs/531921-2002-toyota-tundra-access-cab-center-console-sub.html

many detailed photos and step-by-step descriptions (it's long):

http://forum.sounddomain.com/ubbthreads.php/ubb/showflat/Number/1369669/page/3#Post1369669

 

[PlumbBill 10+ year member]

Good points KHA.

I threw in the nec to show the difference between the ratings ;-)

I hope my previous post didn't come across as what fuse per IASCA awg recommendations. I was just trying to emphasize the importance of a fuse at the battery & what that fuse actually protects.

 

[Merciless 10+ year member]

So we are talking 8AWG for the amp with a 60A fuse.

12AWG for the sub

14-16AWG for the speakers

I can only find 16-18 ft. of amp power cable on kits. Is this enough to reach from the trunk to the engine bay on a Grand Prix GTP (medium size car, kinda long)?

Then my complete list of stuff I need is

HU

amp

speakers

sub.

adapter to fit my HU to my car

speaker wiring

sub wiring

amp power wire

amp ground wire

amp remote start wire

RCA's from HU to amp

Ring terminals (to ground amp)

Bolt on frame

Battery terminals

Spilt loom

Zip ties

Is that everything?

What do you mean by battery adapters?

Thanks!

 

[disturbed471985 5,000+ posts]

I dnt see a box in that list..

Just an example of what he means by batt adapters there are really dozens of different styles to choose from - Negative Battery Terminal

 

[Merciless 10+ year member]

Ohhh, so my 8 gauge power wire can connect to the battery. Thanks

So new list //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

HU

amp

speakers

sub.

sub box

electrical adapter to fit my HU to my car's system

install kit to mount HU

speaker wiring

sub wiring

amp power wire

amp ground wire

amp remote start wire

RCA's from HU to amp

Ring terminals (to ground amp)

Battery adapter

Bolt on frame

Battery terminals

Spilt loom

Zip ties

Thanks for all the help! I just want to ensure I get everything in one trip //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[Merciless 10+ year member]

Ok so I have some specific stuff picked out, and just need your guys ok.

Already have-

HU- Kenwood

AMP- Alpine MRV-F353

Sub- JL W1 10"

Box- JL Stealthbox (Sealed)

Going to buy-

Speakers- Polk DB5251

eBay - New & used electronics, cars, apparel, collectibles, sporting goods & more at low prices

HU Wire Harness for my car-

Don't know which one is right!!!!!!

http://www.amazon.com/gp/product/B0002BEX8W/ref=ox_sc_act_title_1?ie=UTF8&m=ATVPDKIKX0DER

or

http://www.ebay.com/itm/220934254963?ssPageName=STRK:MESINDXX:IT&_trksid=p3984.m1436.l2649

I am leaning towards the amazon one, but don't know. One is 70-1858, one is 71-1858

HU Antenna Harness for my car-

http://www.amazon.com/gp/product/B0002BEQN4/ref=ox_sc_act_title_2?ie=UTF8&m=A17Y7218I8U3RT

Install Kit for my dash-

http://www.ebay.com/itm/180807844129?ssPageName=STRK:MESINDXX:IT&_trksid=p3984.m1436.l2649

Speaker Wire (16AWG)

eBay - New & used electronics, cars, apparel, collectibles, sporting goods & more at low prices

Amp Install Kit- (Power, Ground, Remote Start, 12AWG Wire for Sub, RCA Cable, conduit, 60A fuse, etc. etc.)

eBay - New & used electronics, cars, apparel, collectibles, sporting goods & more at low prices

This should cover everything in my previous list except for the battery adapter. I looked at my battery, and it has one wire coming out, which then goes into a factory adapter, which spilts it into two. Could I just piggyback my power cord onto the factory adapter?

For the wire from my amp to sub, I am just going to use the included 12AWG with the kit. Is this ok?

Are my no-name amp kit and speaker wire ok?

Are my harnesses ok for my 99 GTP?

Is there anything else I could need?

Finally, I was looking at the MRV-F353's manual. Here is a link.

http://vault.alpine-usa.com/products/documents/OM_MRV-F303.PDF

Scroll down to page 14, and you should see the "3 Channel System" for the F353 amp. It shows the set-up I am doing (Channel 1-4 bridged to my front speakers, and Channel 5 to my sub). My only problem is that is suggests running only one RCA to the amp for signal. Will I still get all the features and adjustments with the sub using Channel 1+3's signal?? In other words, would I gain anything by running another RCA to Channel 5 (the sub)?

Thank you so much!

You guys are great

 

[keep_hope_alive Premium Member]

You do gain the benefit of sub level control At the HU with a separate input to channel 5.

The Metra harness starting with 70- is into the car, you want this one. The other starting with 71- is into radio, you don't need it.

 

[Merciless 10+ year member]

Thanks.

I am going to buy a second RCA.

Another question I had was on my amp kit. It looked like an awesome deal, but I found a review saying it was like 22 gauge power wire in an 8 gauge shell. That is the only review really on it.

Could you guys recommend an amp install kit? I just want it to work decent, and not cost so much (I'd like to spend 30 bucks or less).

Or could you just recommend a good brand?

Thanks again!!!!!!!!

 

[Merciless 10+ year member]

I think I am just going to go with the KnuKoncepts Fleks kit.

8 Gauge Amplifier Installation Kit

It has a 50A fuse, which should still be fine.

Bigger problem is that it includes no terminals for the 12 gauge wire (my sub wire). I believe I would need 4 12AWG Spade Terminals, correct?

And then I would need 8 16AWG Spade Terminals to connect my two speakers to my amp?

 

[05trailblazer 10+ year member]

omg!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

[Merciless 10+ year member]

Ok, finally have everything ready to go.

I already have HU, sub, sub box, and amp.

I am buying-

Speakers-

eBay - New & used electronics, cars, apparel, collectibles, sporting goods & more at low prices

Speaker Wire-

eBay - New & used electronics, cars, apparel, collectibles, sporting goods & more at low prices

16AWG Spade Terminals

http://www.ebay.com/itm/Xscorpion-ST10B-ST-10-Blue-100-Pack-10-16-14-Gauge-AWG-Spade-Terminals-/360428072112?pt=LH_DefaultDomain_0&vxp=mtr&hash=item53eb2fecb0

Amp Kit

8 Gauge Amplifier Installation Kit

Extra RCA in addition to one in Amp Kit

Knukonceptz product detail for KLARITY RCA CABLE 2 CHANNEL RCA KABLE 5 METER

Spade Terminals for the 12AWG (my sub wire) in Amp Kit

eBay - New & used electronics, cars, apparel, collectibles, sporting goods & more at low prices

Install Kit

eBay - New & used electronics, cars, apparel, collectibles, sporting goods & more at low prices

HU Harness

http://www.amazon.com/gp/product/B0002BEX8W/ref=ox_sc_act_title_1?ie=UTF8&m=ATVPDKIKX0DER

Radio Harness

Amazon.com: Metra 40-GM10 GM Antenna Adapter: Car Electronics

I am going to need 24 16AWG Spade Terminals correct? Because the crossovers have 6 each, times two gives 12 on the crossovers alone. Time two again gives 24 total.

Good thing I caught that! Half way through install. We are out of spade terminals......... ****....... lol

Last question I had was if the mids and tweeters take a spade terminal?

Anything else you guys can think of??

 

[keep_hope_alive Premium Member]

speakers use a female disconnect. typicall 0.205 on positive an 0.110 on the negative. get some 0.205 female disconnects (fully insulated) and some 0.187 fully insulated.

DISCONNECT TERMINALS from Parts Express ship same day and come with 45 day money back guarantee. Free Shipping Available. Order free 10,000 product catalog.