I know many don't like Capacitors but...
04-01-2006, 07:04 PM
#1
0 Watt CAFz'r
Thread Starter
Join Date: Oct 2005
Posts: 35
I know many don't like Capacitors but...
Can a person safely connect TWO separate 4 gauge power wires (from the same battery) to one capacitor? Off this same cap, then power two 600 watt RMS subwoofer amplifiers?
Or would one 4 gauge power wire to the cap be large enought for 1300 watts RMS?
Just wondering if would damage the cap or something. YIKES!
Or would one 4 gauge power wire to the cap be large enought for 1300 watts RMS?
Just wondering if would damage the cap or something. YIKES!
04-01-2006, 07:12 PM
#2
0 Watt CAFz'r
Join Date: Mar 2006
Posts: 19
one 4 gauge wouldnt be enough for 1300w rms, but instead of 2 4awg wires why not just run a 2awg or a 0?
and for 1300w rms make sure you have a big enough cap. Over 2 farad for sure.
But yeah i dotn see what would damage the cap from running 2 seperate 4awg wires, its juts like having 1 2awg wire. cap doesnt know the diff.
and for 1300w rms make sure you have a big enough cap. Over 2 farad for sure.
But yeah i dotn see what would damage the cap from running 2 seperate 4awg wires, its juts like having 1 2awg wire. cap doesnt know the diff.
04-02-2006, 08:33 PM
#6
Running 1/0 power wire to 1300 watts of amplifiers is massive over kill.
One 4 AWG would be acceptable with 1 or 2 farads of capacitance.
If you wanted to do it 'right' a 2 AWG would be best. Running (2) 4 AWG power wires is more work, harder to install and has more connections which is not ideal.
That being said, (2) 4 AWG wires is the equvilent of 1 AWG with the added advantage of lower ESR.
One 4 AWG would be acceptable with 1 or 2 farads of capacitance.
If you wanted to do it 'right' a 2 AWG would be best. Running (2) 4 AWG power wires is more work, harder to install and has more connections which is not ideal.
That being said, (2) 4 AWG wires is the equvilent of 1 AWG with the added advantage of lower ESR.
04-02-2006, 09:05 PM
#7
Going with 0 guage would simplify the installation over running 2 runs of 4 guage, and with the price differential between 2 and 0 I would just do it "right" the first time. That way, if upgrading to something with even more power comes along down the road it'll be a plug and play situation. Plust 0 is just plain impressive 
.
.
04-03-2006, 05:47 PM
#10
Lets look at some numbers. You amps put out 600 watts rms, and assuming they are the pioneers GM510M, that is about 1000 watts peak into 2 ohms (from the datasheet/web site)
It is a class D amp, that is maybe 90% efficient, so that is 1100 watts power consumption. At 12 volts you then get
1100/12 = 90 amps peak current PER AMP. With 2 amplifiers that is 180 AMPS peak. First if you want to get that much power, you need to upgrade your altenator and battery. Bet lets assume you have or will. Lets also assume that you need 15 feet of wire to get from your battery to your trunk. AWG4 has .25 milliohms per foot, or 3.75 milli ohms total resistance. Using equation Watts= I^2xR we get 180x180x3.75mohms =121 watts of power dissipated in the 4 gauge wire. That is not trivial, but it only happens occasionally on peak demand, and certainly not while you are in the car, since your eardrums will blow if you are pushing 2000 watts peak thru the subs. Another calculation from ohms law (V=IxR) V=180X3.75mohms =.675 volts lost from the battery to the amp, when drawing peak current. The above calculations are approximate, but should be withing 10% or so. This is the way that you need to look at the issue. You need to put some data behind the guesses and opinions. You need to ask the questions; Why do you need this or that. The answers should be based on calculations that can be backed up and proven.
Using 2 AWG wire would halve the power dissipated in the wire and halve the voltage drop.
Here is a simple table of resistance per foot vs AWG size.
AWG mohms/ft
0 0.1003
1 0.1264
2 0.1593
4 0.2533
8 0.6405
10 1.018
So you decide. what you want to do. If this is an SPL car, then certainly run AWG1 or0 cable. But for everyday listening, AWG 2 or 2 runs of AWG4 is ok. AWG 2 will be cleaner, fewer fuses, connectors etc.
As for the Cap, there is no way that a 1 farad cap is going to make a shred of difference with 180 amps of current being drawn.
Here is a good general site to help you learn about car audio: http://www.bcae1.com/
There is a good section on Caps, and the author concurs with my opinion and others that do not make profits selling caps (most car audio shops make lots of profit selling caps) that caps don't do a thing. I know that the dealers reading this will not like to hear this, but they will not be able to prove otherwise. Bring the cap back to where you purchased it and trade it in for some lower gauge wire and good connectors, grounding block, fuse holder etc.
It is a class D amp, that is maybe 90% efficient, so that is 1100 watts power consumption. At 12 volts you then get
1100/12 = 90 amps peak current PER AMP. With 2 amplifiers that is 180 AMPS peak. First if you want to get that much power, you need to upgrade your altenator and battery. Bet lets assume you have or will. Lets also assume that you need 15 feet of wire to get from your battery to your trunk. AWG4 has .25 milliohms per foot, or 3.75 milli ohms total resistance. Using equation Watts= I^2xR we get 180x180x3.75mohms =121 watts of power dissipated in the 4 gauge wire. That is not trivial, but it only happens occasionally on peak demand, and certainly not while you are in the car, since your eardrums will blow if you are pushing 2000 watts peak thru the subs. Another calculation from ohms law (V=IxR) V=180X3.75mohms =.675 volts lost from the battery to the amp, when drawing peak current. The above calculations are approximate, but should be withing 10% or so. This is the way that you need to look at the issue. You need to put some data behind the guesses and opinions. You need to ask the questions; Why do you need this or that. The answers should be based on calculations that can be backed up and proven.
Using 2 AWG wire would halve the power dissipated in the wire and halve the voltage drop.
Here is a simple table of resistance per foot vs AWG size.
AWG mohms/ft
0 0.1003
1 0.1264
2 0.1593
4 0.2533
8 0.6405
10 1.018
So you decide. what you want to do. If this is an SPL car, then certainly run AWG1 or0 cable. But for everyday listening, AWG 2 or 2 runs of AWG4 is ok. AWG 2 will be cleaner, fewer fuses, connectors etc.
As for the Cap, there is no way that a 1 farad cap is going to make a shred of difference with 180 amps of current being drawn.
Here is a good general site to help you learn about car audio: http://www.bcae1.com/
There is a good section on Caps, and the author concurs with my opinion and others that do not make profits selling caps (most car audio shops make lots of profit selling caps) that caps don't do a thing. I know that the dealers reading this will not like to hear this, but they will not be able to prove otherwise. Bring the cap back to where you purchased it and trade it in for some lower gauge wire and good connectors, grounding block, fuse holder etc.
