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Discussion Starter #1
So I bought the JL GM-D8701 Mono amp..
Amp parameters are
300W x 1 x 4ohm
500W x 1 x 2ohm
800W x 1 x 1ohm..
So I also got two Kicker 10” C104 SVC Subs and I’m putting them into a Dual 10” box in my silverado crew cab under the back seat.. The box is ported with 1.12 cu space per sub..
So my question is... The subs I bought are rated at 300W peak (150 RMS) and I know I would have to run them in parallel to get a 4ohm final impedance.. Should I do that Or should I return the subs and get 2 DVC kicker CVR102 2ohm subs.. and then hook those up for a final 2ohm impedance because they are rated at 700W peak ( 350 RMS) and get more output out of my amp?? Please help me decide.. I HAVE NOT HOOKED ANYTHING UP.. Trying to do as much research as possible to get the best quality as possible and not spend an arm and a leg lol...
I also bought 2Ga OFC to run to the rear into a distribution block and the 4ga OFC to the amp.. Truck is a 2500 Silverado Duramax so I’m not worried about my battery or alternator at all, but I just want maximum performance for what I have.. Again I HAVE NOT HOOKED ANYTHING UP YET..
 

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Discussion Starter #3
Parallel or series?
If I’m not mistaken, the two SVC 4 ohm subs would have to be parallel to be a 4ohm final impedance at the amp. Honestly my whole question is should I stick with the two SVC even though my amp can produce more than the subs can handle or get the DVC 2 ohm subs and wire them to be a 2ohm final at the amp so I get closer to my amps potential
 

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If I’m not mistaken, the two SVC 4 ohm subs would have to be parallel to be a 4ohm final impedance at the amp. Honestly my whole question is should I stick with the two SVC even though my amp can produce more than the subs can handle or get the DVC 2 ohm subs and wire them to be a 2ohm final at the amp so I get closer to my amps potential
I believe you are mistaken.


If they have dual voice coils (VC) then
4-ohms VC parallel with the other 4-ohms VC makes 2-ohms.
Then two subs in parallel at 2-ohms each make 1-ohm at the amp.
In series they make 4-ohms at the amp.

2-ohm VC can be wired as a 4-ohms or 1-ohm for each individual sub.
Then each sub gets wired in parallel or series with the other sub.

If they are single VC then:
each 4-ohm sub parallel with the other 4-ohm sub makes 2-ohms at the amp.
In series they make 8-ohms

Two 1-ohm subs in series make 2-ohms, and in parallel make 0.5-ohms.
Two 2-ohm subs can be either 1-ohm or 4-ohms.

So your 2 SVC 4-ohm subs in parallel would be 2-ohm at the amp.
 

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Discussion Starter #6
ok.. So I have the two SVC 4Ohm coming in tmr.. Your saying if I run each one in parallel with the other than I’ll be at 2ohm at the amp.. should I do that? The subs are rated at 150RMS each.. amp is rated 300RMS if at 4ohm
 

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ok.. So I have the two SVC 4Ohm coming in tmr.. Your saying if I run each one in parallel with the other than I’ll be at 2ohm at the amp.. should I do that? The subs are rated at 150RMS each.. amp is rated 300RMS if at 4ohm
Who cares what the amp is rated at for 4-ohms?
Two 4-ohm subs in parallel presents an impedence at the amp of 2-ohms.

Question 1) Is the amp rated for 2-ohms?

If the answer is no, then get two 2-ohm subs and wire them in series, or get an amp rated for 2-ohms.
 

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Discussion Starter #8
Who cares what the amp is rated at for 4-ohms?
Two 4-ohm subs in parallel presents an impedence at the amp of 2-ohms.

Question 1) Is the amp rated for 2-ohms?

If the answer is no, then get two 2-ohm subs and wire them in series, or get an amp rated for 2-ohms.



Yes it is
 

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Discussion Starter #9
i understand it’s frustrating dealing with someone who doesn’t know what their talking about.. please bare with me.. trying to learn and not just hook just anything up
 

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Wiring in Parallel equation 1/Rt= 1/R1 + 1/R2 + 1/R3
Rt= resistance total
R1= resistance 1 R2= resistance 2 and so on
R1= 4ohm (1÷4=.25)
R2= 4ohm (1÷4=.25)
1/Rt= .25 + .25
1÷.5= 2 ohm
 

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Wire the two 4ohm single coil subs in parallel with your amp (all three "+" together, all three "-" together)

You now have a 2ohm load (safe, as your amp is 1ohm capable) but too much power, so just wind the gain down. Just be listening out for distortion as you gradually increase levels (and maybe gains) as you play the system to begin with.

Also be aware, we don't hear distortion as easily in the sub frequencies, so be careful and make gradual increases. If the amp or your head unit has a subsonic or infrasonic filter (rolls of some of the deepest bass) use that to help those subs out...
 

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i understand it’s frustrating dealing with someone who doesn’t know what their talking about.. please bare with me.. trying to learn and not just hook just anything up
That is not frustration.
Frustrating is hooking up, releasing magic smoke, and then hear them swearing that they know it all.

Wiring in Parallel equation 1/Rt= 1/R1 + 1/R2 + 1/R3
Rt= resistance total
R1= resistance 1 R2= resistance 2 and so on
R1= 4ohm (1÷4=.25)
R2= 4ohm (1÷4=.25)
1/Rt= .25 + .25
1÷.5= 2 ohm
^This is good and accurate.^

You'll want to work it out with a sharp pencil. It was the same magic that I used earlier in post #5.
You better check it as I did it my head, so I could have been wrong... (it is really best to double check, I think.)
 
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