Audio Systems: dvc 2ohm sub wiring ?, rockford fosgate, mono amp

Question
QUESTION: i have a rockford fosgate 15" t215d2 dvc sub and a 1800 watt kenwood KAC-9104D monoblock amp and dont know how to wire it. the amp has 2(+)and 2(-) side by side so it looks like on the amp: [++][--]. so i hooked all of it up to the sub and it dosnt sound right i hooked both positives to the 2 on the sub and same with the negatives. i was reading and sum places say u cant get a 2ohm load with just one 2ohm sub? so im lost on how to wire it right for maximum power
thanx , Jake

ANSWER: It is an outstanding sub woofer!   Good amp too.

The Kenwood is a mono block amp, meaning that it has only one amplifier inside.

So, your best connection would be to wire the two voice coils in parallel.  You can connect the plus of coil number one to a + terminal and the - terminal to the - amp.  Connect the other voice coil to the other set of speaker connections.

http://akamaipix.crutchfield.com/ca/learningcenter/car/subwoofer_wiring/1DVC_2-o

and for other configurations, fyi, see:

http://www.crutchfield.com/S-UODK7HeEmNh/learn/learningcenter/car/subwoofers_wir

Best wishes,
C
C



---------- FOLLOW-UP ----------

QUESTION: Ok so I think I get what u mean but still a lil confused cuz the links u put on there only showed how to wire it to 4ohm , n I tryed that n it barly moves . So what ir sayin is connect one voice coil to one set of the + and - on the mono amp and connect the other voice coil to the remaining + and - on the amp ......or connect one voice coil to one set of the + and - on amp and just connect wires from the connected coil to the other side of the sub ?? ...... sry if its a stupid ? I jes wanna make sure cuz right now im kinda dissapointed with all of it for not workin but ill asked u more if its just my vehical too after I get a final answer 4 the sub wiring and get that dun and see how it goes

ANSWER: You have one amplifier (but it has two output terminals which are just in parallel with each other - it is for convenience when wiring up parallel speakers).

You have one speaker which has two voice coils.

You want to parallel the voice coils; plus to plus and minus to minus on the woofer. (It makes no difference whether the parallel connections are done at the woofer terminals or at the amplifier terminals.)

Then you want to connect the paralleled coils to the one amplifier.

Doing so will make the impedance 1/2 of the impedance of each coil independently.  Since the voice coils are 2 ohms each, the resulting impedance when in parallel will be 1 ohm.

The amplifier is 1 ohm stable, so this will work just fine.

Good Luck,
C




---------- FOLLOW-UP ----------

QUESTION: ok so i wired like u were sayin , but did it as one voice coil to one set of the termanils on amp and the other voic coil to the remaining + and minus on amp. cuz i was thinkin bout it and it should be the same so i get the 1 ohm load since even tho the amp has 2 sets of plus and minus termanils , they actually connect inside as one right? so it should be the same just ther is no wires goin from one side of speaker to other . so that should be right?

Now for the second part...(right off the bat so u kno i dont have the custom box dun if that will make a diff. to see if it sounds good.) so i got all 0 g. wiring from front to back with a didioe battery isolator and from that its wired to an optima yellow top battery with the ground 2 feet from battery and 1 foot from amp and bout 1 foot positve from battery to amp . so i though it would be all good and play right? well it dosnt but since i wired it it sound better than before but now if i turn up the sound only bout half it seems that it still drawing power from everything not as much as when i hooked it up to just the stock battery in the truck but then it also blows fuses left and right if i turn it up? so idk if i need a biger alternator or what?

Answer
Right, right.  Right on.

If a sub woofer is not in an appropriate box you will get very little out of it.  Why?  Because the air being pushed as the cone moves forward just goes around the sides of the woofer frame and cancels out with the vacuum on the back side of the cone!

So, you MUST have the woofer mounted in a box in order to get any idea of what it is going to sound like.

Once you get it sounding pretty good you can then decide - from checking the battery voltages - whether you will need a bigger battery and/or oversize alternator!

Best to you,
C