Fordmods Logo

have i been told wrong? - amp wiring 

 

Page 1 of 2 [ 19 posts ] Go to page 1, 2  Next

 
 Post subject: have i been told wrong? - amp wiring
Posted: Sat Jul 28, 2007 6:06 pm 
Stock as a Rock
Offline

Posts: 121

Joined: 18th Mar 2007

Ride: EL Fairmont

Location: Melbourne
VIC, Australia

g'day all...i went and bought 2 amps the other day and wiring kits and everything from jb. monoblock 800wrms and 600wrms 4 channel audiobahns....and i bough a $200 stinger wiring kit as the dude did me a great price. now only thing is i asked if the kit was enough for the two amps and he said yea its fine......so what he told me to do is run the 4 gauge from the battery into the 150amp fuse, then run it to the back seat where the amps are mounted and use a splitter box and then run 2 seperate 4 gauge wires to each amp....ive done this but soo far only had time to do the monoblock and it sounds great but im not sure if this will supply enough power for the speaker amp aswell?? or will it?

 

_________________

Live, Play, Work - FORD

Top
 Profile  
 
 
Posted: Sat Jul 28, 2007 7:15 pm 
Getting Side Ways
Offline
User avatar

Posts: 2943

Joined: 24th Jan 2005

Gallery: 18 images

Ride: XW, EL, Territory, VFR800

Power: 129 rwkw

Location: Adelaide
SA, Australia

Check this site out mate... Will help you: http://www.bcae1.com/wire.htm 4G wire will carry roughly 130amps so it should be fine for your two amps.

However, 2G direct from the battery to a distribution block then 4G to each amp would be ideal.
Top
 Profile  
 
 
Posted: Sat Jul 28, 2007 7:17 pm 
Getting Side Ways
Offline
User avatar

Age: 36

Posts: 2159

Joined: 15th Nov 2005

Gallery: 17 images

Ride: TS40

Location: Latrobe Valley
VIC, Australia

yeah shouldnt have a problem with that size cable... im just running 8 gauge to a 520 wrms amp and it seems fine...

 

_________________

Was - 2001 AUIII Ford Falcon Forte
Genuine T2 TS50 bodykit, 18" BF Cobras, Boge and Eibach Suspension and Complete AU2 Fairmont Ghia Interior

Now - 2012 FG Mk2 Ford Falcon XR6
Swift Green,6 Speed Auto, Stock... and a Fuel Card :)

Top
 Profile  
 
 
Posted: Sat Jul 28, 2007 9:24 pm 
Fordmods Junkie
Offline
User avatar

Posts: 11752

Joined: 17th May 2005

Gallery: 11 images

Ride: EL Fairmont, VFR400 racer

Power: 144 rwkw

Location: Melbourne
VIC, Australia

agreed with the 2 above me...should work fine. Though as mongoose said, 2Gauge wiring from the engine to the boot would be better, though not really necessary. Make sure you have another fuse in the engine bay...don't want you to burn the interior if there was ever to be a short.

phong =P~

 

_________________

phongus = Post whore 2006
EL XR6 motor, EL ECU + J3 chip, WADE 1673 Camshaft, 3" S/S intake, Pacy 4480, 2.5" Hi flow cat, 2.5" Lukey exhaust.
Max Power = 144.6 rwkw (03/05/2008)

Top
 Profile  
 
 
Posted: Sat Jul 28, 2007 10:23 pm 
Getting Side Ways
Offline
User avatar

Age: 38

Posts: 11105

Joined: 15th Nov 2004

Ride: No Fords current

Location: Hobart
TAS, Australia

yeah you'll have no dramas.

Unlike this bloke that came into work today - he's just bought a Powersomething 5000W 2 channel amp (yes 5000W!!!), and he's worried about weather the big thich a** cable will be enough to power it. The thing probably has as much power as the amp in my CD player...
In the end I told him to try Arora (our local power supplier - like the mob that supply power to your house/business and own the power lines in the street) and they should be able to hook him up (I was being a smart a**) - he didn't relise and said ah yeah that'd be a good idea...
Top
 Profile  
 
 
Posted: Sat Jul 28, 2007 11:05 pm 
Stock as a Rock
Offline

Posts: 121

Joined: 18th Mar 2007

Ride: EL Fairmont

Location: Melbourne
VIC, Australia

haha classic mate....gotta love those customers that think there on a good thing but really got no idea and act like they do haha....cheers fellas

 

_________________

Live, Play, Work - FORD

Top
 Profile  
 
 
Posted: Sun Jul 29, 2007 12:18 pm 
Getting Side Ways
Offline
User avatar

Age: 38

Posts: 900

Joined: 14th Mar 2007

Location: Castlemaine
VIC, Australia

Running 8gauge into the positive terminal from the distribution block should be enough, something you may not know is that you should run a BIGGER NEGATIVE lead, as the power comes from the negative terminal :)
I run 4gauge into the boot, fuse under the bonnet to the distributor, 8gauge to the amps and 4gauge negatives.

One amp has the negative wire wrapped around the big screw holding the gas tank down, then it duck taped up :)
Matt

 

_________________

it can be fast and cheap,but it wont be reliable
it can be reliable and cheap,but it wont be fast
or you can be fast and reliable,but it wont be cheap

Top
 Profile  
 
 
Posted: Sun Jul 29, 2007 12:27 pm 
Getting Side Ways
Offline
User avatar

Age: 52

Posts: 582

Joined: 20th Nov 2004

Ride: xr6

Location: Brisbane
QLD, Australia

So can you explain to me why the negative sould be bigger than the positive?
This has me a little confused...

 

_________________

Do it once, Do it right!!!!!!

Top
 Profile  
 
 
Posted: Sun Jul 29, 2007 5:16 pm 
Oompa Loompa
Offline

Age: 36

Posts: 46

Joined: 27th Dec 2006

Location: Wagga
NSW, Australia

because electrons acturley flow from the negative terminal to the positve, caled electron flow , but in actural fact the cable should be the same size because electrons have to flow through both cables an will be limited to the smaller wires capacity, not a issue for a car audio setup tho lol..

conventional current flow is wot people use to beleive how electricty flows. doesn't really matter once again tho lol..

 

_________________

Soon to be the finest Sounding BA Ute

Top
 Profile  
 
 
Posted: Sun Jul 29, 2007 5:18 pm 
Smokin em up
Offline

Age: 42

Posts: 296

Joined: 16th Oct 2006

Ride: 94 EF (OPT20), TF Cortina Ghia

Location: Bendigo
VIC, Australia

^ Spot on buddy.

 

_________________

"Look I found tape, I'm a mechanic now!!!" Mike Teutul

Top
 Profile  
 
 
Posted: Sun Jul 29, 2007 5:21 pm 
Getting Side Ways
Offline
User avatar

Age: 40

Posts: 832

Joined: 5th Nov 2004

Gallery: 7 images

Ride: EL Fairmont

Location: Brisbane
QLD, Australia

the negative is the return path or ground of the vehicle. While i personally think its s**t to have a bigger earth, it should be same size as positive, it wouldnt hurt. make sure you sand the paint back where ever you decide to put the earth.

Oh, and to be really techo, if your going to run big earth for your audio, you should also upgrade the earth from your engine block to battery, and even run more earths from the chassis and body. Only the real hardcore dudes bother

 

_________________

too many rabbits in china

Top
 Profile  
 
 
Posted: Fri Oct 12, 2007 9:36 pm 
Fordmods Newbie
Offline

Posts: 7

Joined: 13th Jul 2005

Location: Auckland
New Zealand

-GAS-MAN- wrote:
Running 8gauge into the positive terminal from the distribution block should be enough, something you may not know is that you should run a BIGGER NEGATIVE lead, as the power comes from the negative terminal :)
I run 4gauge into the boot, fuse under the bonnet to the distributor, 8gauge to the amps and 4gauge negatives.

One amp has the negative wire wrapped around the big screw holding the gas tank down, then it duck taped up :)
Matt


Erm.......rubbish!

The formula for power is P=IV, or P=I^2R. The higher the resistance of the cable, the less current it is able to carry without behaving like a fuse. As the current flowing through both the cables is the same (electrons don't get lost, or consumed.....), you want the longer cable to be heavier gauge than the shorter. It makes sense to just spec big-a*** cable for both.

You are quite correct about the direction of electron flow though (Neg to pos). Any electronics/electrical engineer (Myself included) will tell you that "holes" flow positive to negative
Top
 Profile  
 
 
Posted: Sat Oct 13, 2007 8:23 pm 
Getting Side Ways
Offline
User avatar

Age: 52

Posts: 582

Joined: 20th Nov 2004

Ride: xr6

Location: Brisbane
QLD, Australia

fcollingwood wrote:
-GAS-MAN- wrote:
Running 8gauge into the positive terminal from the distribution block should be enough, something you may not know is that you should run a BIGGER NEGATIVE lead, as the power comes from the negative terminal :)
I run 4gauge into the boot, fuse under the bonnet to the distributor, 8gauge to the amps and 4gauge negatives.

One amp has the negative wire wrapped around the big screw holding the gas tank down, then it duck taped up :)
Matt


Erm.......rubbish!

The formula for power is P=IV, or P=I^2R. The higher the resistance of the cable, the less current it is able to carry without behaving like a fuse. As the current flowing through both the cables is the same (electrons don't get lost, or consumed.....), you want the longer cable to be heavier gauge than the shorter. It makes sense to just spec big-a*** cable for both.

You are quite correct about the direction of electron flow though (Neg to pos). Any electronics/electrical engineer (Myself included) will tell you that "holes" flow positive to negative



Exactly, it is a phallicy that the cables need to be the same size as it is dependent on the current and the cable length, it is a cosmetically good thing to do but it has no basis in ohms law that the super short ground cable has to be the same size as the much longer positive cable let alone needing a larger ground cable which is total crap......
It is amazing some of the garbage that gets sprouted about car audio....

 

_________________

Do it once, Do it right!!!!!!

Top
 Profile  
 
 
Posted: Mon Oct 15, 2007 11:42 pm 
Getting Side Ways
Offline
User avatar

Age: 34

Posts: 2983

Joined: 15th Apr 2006

Gallery: 5 images

Ride: Falcon

Location: Aberfoyle Park
SA, Australia

Really its not going to be an issue what cable you use. I used 8g cable (yes, only about 5mm in diameter) to my 2 channel 500w amp for the sub. Then i went to add the 1000W 4 channel for the speaks and got all worried but then soon realised that is wasnt an issue anyway.

So i have a 8g cable running to a distro block with 2 x 8g cables coming from that for the amps.

As for the earths, i had proper connectors on the bastards and sanded to bare metal on the chassis where the rear seats bolt in. I had both my amps mounted on the back seat.

 

_________________

HOLDENS go like rockets. They fall apart in stages!!!

Top
 Profile  
 
 
Posted: Tue Oct 16, 2007 4:48 pm 
Fordmods Newbie
Offline

Posts: 7

Joined: 13th Jul 2005

Location: Auckland
New Zealand

outlawxr6 wrote:
fcollingwood wrote:
-GAS-MAN- wrote:
Running 8gauge into the positive terminal from the distribution block should be enough, something you may not know is that you should run a BIGGER NEGATIVE lead, as the power comes from the negative terminal :)
I run 4gauge into the boot, fuse under the bonnet to the distributor, 8gauge to the amps and 4gauge negatives.

One amp has the negative wire wrapped around the big screw holding the gas tank down, then it duck taped up :)
Matt


Erm.......rubbish!

The formula for power is P=IV, or P=I^2R. The higher the resistance of the cable, the less current it is able to carry without behaving like a fuse. As the current flowing through both the cables is the same (electrons don't get lost, or consumed.....), you want the longer cable to be heavier gauge than the shorter. It makes sense to just spec big-a*** cable for both.

You are quite correct about the direction of electron flow though (Neg to pos). Any electronics/electrical engineer (Myself included) will tell you that "holes" flow positive to negative



Exactly, it is a phallicy that the cables need to be the same size as it is dependent on the current and the cable length, it is a cosmetically good thing to do but it has no basis in ohms law that the super short ground cable has to be the same size as the much longer positive cable let alone needing a larger ground cable which is total crap......


Yup - I forgot to mention the fact that the longer cable would have a higher resistance, therefore should possibly be the heavier gauge, if there is going to be a heavier gauge in the set up.

outlawxr6 wrote:
It is amazing some of the garbage that gets sprouted about car audio....


Yup too, I see the same in home theatre, and in IT, but I have noticed the cowboys in the industry slowly disappear.
Top
 Profile  
 
Display posts from previous:
Sort by  
 Page 1 of 2  [ 19 posts ]  Go to page 1, 2  Next

Who is online

Users browsing this forum: No registered users and 6 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

 

 

It is currently Wed Nov 27, 2024 9:53 pm All times are UTC + 11 hours

 

 

(c)2014 Total Web Solutions Australia - Australian Web Hosting and Domain Names