Sub Wiring

[whitedragon551 5,000+ posts]

I usually use 12volts woofer wiring or Rockfords woofer wiring wizard. However they dont have options for DVC3 ohm subs. If I remember correctly its either 1/2 or double so it will be a final 1.5 ohm load or a 6 ohm load. Am I remembering correctly?

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[bubbagumper6 5,000+ posts]

Not exactly

When wiring in series you just add the impedance.

Parallel is slightly more complicated, it's 1/Rf = 1/R1 + 1/R2 + ... + 1/Rn

Where Rf is your final impedance and R1, R2, through Rn are your individual coil/sub impedances.

So when you have an even number of coils/subs it works out to just 1/2 but just figured I'd educate you in the process //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[whitedragon551 5,000+ posts]

Fuck this server.

 

[whitedragon551 5,000+ posts]

I suck at math, but Ill give this a shot. I found this on TermPro:

Equation 1: Speakers in SeriesZt = Za + Zb

Consider this real-world example of series wiring. Say you have a yearning for ultra-low bass – the kind that loosens the weather stripping around your windows – and you're determined to install four 15-inch subwoofers in your car. The amplifier you've reserved for this task delivers 100 watts x 2 into 4 ohms and is capable of driving a minimum load impedance of 4 ohms; the subs are rated at 4 ohms apiece.

Assuming there's enough room in your car for these monsters, the only viable option – given the above scenario – is to wire two subs in series to each amplifier channel. Doing so raises the net, or equivalent-load, impedance of each channel to 8 ohms – well within our standard 16-ohm ceiling. Mathematically, you substitute 4 ohms (the impedance rating of each sub) for Za and Zb in Equation 1 and work it through as follows:

Zt = Za + Zb

Zt = 4 + 4

Zt = 8 ohms

Parallel wiring, which we'll discuss later, isn't advisable here because the net impedance for each channel drops below the minimum-load rating of the amplifier.

Equation 4: Speakers in ParallelZt = (Za x Zb) / (Za + Zb)

Turning again to our subwoofer install, say you want even more oomph from your system. So you trade in the original amp for one that has the same 4-ohm power rating (100 watts x 2) but is also 2-ohm stable. Since the power output of most amps increases as impedance decreases, you could boost the amp's power output and the system's bass response simply by switching to a parallel wiring scheme. Doing so would drop the net, or equivalent-load, impedance for each channel to 2 ohms. Mathematically, you substitute 4 for Za and Zb in Equation 4 and work it through:

Zt = (Za x Zb) / (Za + Zb)

Zt = (4 x 4) / (4 + 4)

Zt = 16 / 8

Zt = 2 ohms

To calculate the new amplifier's power output into 2 ohms, refer to Equation 2. Plugging in the appropriate numbers, the calculation goes as follows:

Po = 100 x (4 / 2)

Po = 100 x 2

Po = 200 watts

As you can see, by upgrading to a 2-ohm-stable amplifier and wiring the same four 15-inch woofers in parallel – two per channel – power output jumps fourfold – from 50 watts x 2 to 200 watts x 2.

So for series I would have Zt = Za + Zb which is Zt=3+3 so Zt=6 ohm final load

For parallel I have:

Zt = (Za x Zb) / (Za + Zb)

Zt = (4 x 4) / (4 + 4)

Zt = 16 / 8

Zt = 2 ohms

Zt= (3x3)/(3+3)

Zt=9/6

Zt=1.5 ohms

So my options are a 6 ohm final load or a 1.5 final load at the amp.

Shiz. I hope after imp rise Im at 2 ohms.

 

[bubbagumper6 5,000+ posts]

I suck at math, but Ill give this a shot. I found this on TermPro:




So for series I would have Zt = Za + Zb which is Zt=3+3 so Zt=6 ohm final load

For parallel I have:

Zt = (Za x Zb) / (Za + Zb)

Zt = (4 x 4) / (4 + 4)

Zt = 16 / 8

Zt = 2 ohms

Zt= (3x3)/(3+3)

Zt=9/6

Zt=1.5 ohms

So my options are a 6 ohm final load or a 1.5 final load at the amp.

Yes. That's just a shortcut formula for when you only have two impedances, it doesn't work if your trying to calculate 3 or more in parallel.

 

[bubbagumper6 5,000+ posts]

double post //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

 

[whitedragon551 5,000+ posts]

Alright anyone have a wiring diagram for this? I dont want to F up. Im going for a 1.5 ohm at the terminal cup.

 

[95BlackGA 5,000+ posts]

If you're wiring for 1.5 and you have a SINGLE DVC 3ohm woofer, wiring in parallel (positive to positive, negative to negative). If you have TWO DVC woofers, you WILL NOT get 1.5 ohms. You will either get .75 (Parallel), 3 (Series each woofer to 6ohm, then parallel the 2), or 12 ohm (Series all).

 

[whitedragon551 5,000+ posts]

If you're wiring for 1.5 and you have a SINGLE DVC 3ohm woofer, wiring in parallel (positive to positive, negative to negative). If you have TWO DVC woofers, you WILL NOT get 1.5 ohms. You will either get .75 (Parallel), 3 (Series each woofer to 6ohm, then parallel the 2), or 12 ohm (Series all).

Look at the math and re-read the OP. Its a single woofer thats got DVC3 ohm coils.