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Amp suggestion for 10" Rockfort Fosgate HE2

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Amp suggestion for 10" Rockfort Fosgate HE2

  • I have a single Rockfort Fosgate 10" Punch HE2 from roughly 2003.

    A buddy of mine picked these up when they were new and sold me one of them recently. I'm a relative newb to car audio, and have just started to read a lot of the articles and understanding some of it. 

    My understanding based on what I've read is that I can work these at either 2 or 4 ohms. 

    They are rated for 800W peak and 400W RMS power and are DVC subs.  Running in a enclosed cabinet.

    I'm looking for amp and wiring suggestions.  The car is an '02 Subaru WRX Sport Wagon.  Currently I'm running the regular factory speakers and just installed a DEH-P980-BT Premier Pioneer headunit.

     I'm not necessarily looking for a loud sound, just looking for the clearest sound with a decent hit.  I'm not typically playing the stereo loud, but I've been a musician most of my life and I have a good ear.

     Explainations would also be appreciated.  I'm trying to learn, but I'd hate to learn anything the hard way because it seems that involves melting at some point.

     Thanks

              Derek

  • It'll be hard to pick an amp unless you can give us the Ohms of that DVC sub. They are either going to be DVC2ohms or the DVC4ohms model, but it does matter which model you have.

    If you cannot tell from any of the markings on the subwoofer, you can read this thread to get an idea of how to find out using a multimeter. 

     Pzaul



    [edited by: pzaul at 9:57 AM (GMT -5) on Fri, May 25 2007]
    Kenwood X491, Epic 150 HO Alternator, 1/0 Gauge Big 3 Sony XM-4S, Hifonics BXi 2006D Clarion SRR1027, Infinity Reference 6022si 2 12" TC-2000's Sealed 1.0 cu per Only 140db w/music: work in progress
  • pzaul:

    It'll be hard to pick an amp unless you can give us the Ohms of that DVC sub. They are either going to be DVC2ohms or the DVC4ohms model, but it does matter which model you have.

    If you cannot tell from any of the markings on the subwoofer, you can read this thread to get an idea of how to find out using a multimeter. 

     Pzaul

    They're marked as 4 ohms... So I'm pretty sure they are the DVC 4 ohms models.  I'll double check that tonight when I get home and make sure I'm positive.

  • A single 4ohm dvc subwoofer can be wired for 2ohm or 4ohm. Your best bet is to go 2ohm and find a mono block class d amplifier. This alpine would work great and be well matched with your subwoofer at 400rmsx1 @2ohm. Theres others out there, better quality or cheaper; whichever way you wanna go. Just keep the rms at 2ohms around 350-450rms x 1. That thing will pound like nobodies business and be nice and clean in that sealed enclosure.

    Pzaul
     



    [edited by: pzaul at 10:26 AM (GMT -5) on Fri, May 25 2007] [edited by: pzaul at 10:26 AM (GMT -5) on Fri, May 25 2007]
    Kenwood X491, Epic 150 HO Alternator, 1/0 Gauge Big 3 Sony XM-4S, Hifonics BXi 2006D Clarion SRR1027, Infinity Reference 6022si 2 12" TC-2000's Sealed 1.0 cu per Only 140db w/music: work in progress
  • Thanks for the suggestion... hopefully this will help with the advice. 

    Decided a picture may be worth a thousand words on this one.

     Model # is RFP3210 in case you can't read it.

     

  • pzaul:

    A single 4ohm dvc subwoofer can be wired for 2ohm or 4ohm.  



    That should say "A single 4ohm dvc subwoofer can be wired for 2ohm or 8ohm." (I think?)

    2002 Ford Focus JVC KD-A815 Sony CDX-GT410u Sony XT-100HD HD Tuner Stock speakers, no amp, no subs

  • I think I meant 2ohm or 8ohm, yes sorry heh. It can be wired to one vc and run the amplifier at 4ohm, but that wouldnt make too much sense if he hasnt picked an amplifier yet.

    Pzaul 

    Kenwood X491, Epic 150 HO Alternator, 1/0 Gauge Big 3 Sony XM-4S, Hifonics BXi 2006D Clarion SRR1027, Infinity Reference 6022si 2 12" TC-2000's Sealed 1.0 cu per Only 140db w/music: work in progress
  • Thanks for the replies, I'm a relative newb to the car audio side of modifying cars so I've still got a large learning curve.

    So this thing could be wired for 2ohms, 4ohms, and 8ohms?

     Would 2 ohms be the best application of this sub?  Pzaul, would you still recommend that Alpine or do you have a few more recommendations now???

     Thanks in advance for the help.

    Derek

  • WolfSong:

    So this thing could be wired for 2ohms, 4ohms, and 8ohms?

     Would 2 ohms be the best application of this sub?  Pzaul, would you still recommend that Alpine or do you have a few more recommendations now???

    That amp is still fine, nothings changed that I said cept I made the mistake of saying 4ohm instead of 8ohm. You are still going to want to wire it in 2ohm's to a probably mono class d amplifier. Yes you could wire it as 4ohm, but that's not a recommended way.

    Pzaul 

    Kenwood X491, Epic 150 HO Alternator, 1/0 Gauge Big 3 Sony XM-4S, Hifonics BXi 2006D Clarion SRR1027, Infinity Reference 6022si 2 12" TC-2000's Sealed 1.0 cu per Only 140db w/music: work in progress
  • Sorry to keep asking questions, this would be the correct way to wire it?

    I was wondering because it's showing a 4 ohm load at the speaker...

    Thanks

    Derek

  • You got it.

    Technically, it is showing a 4-ohm load on each voice coil of the speaker, which is what you have, and a 2-ohm load on the amp, which is what you want.

    Good job finding that!!!

    2002 Ford Focus JVC KD-A815 Sony CDX-GT410u Sony XT-100HD HD Tuner Stock speakers, no amp, no subs

  • I can see how the diagram may be confusing, so, I thought I'd attempt to offer a little clarity on the point of impedance shown in the diagram.

    I know what TigerHeli means, but, there is no load on each voice coil of the speaker: the speaker is the load (each voice coil presents 4-ohms of resistance) and wired in this configuration (parallel) ultimately presents a 2-ohm load (of resistance) to the amp.

    Clear as mud? Wink

    Don
    Community Manager

  • Clearer than the way I worded it.  Thanks!

    2002 Ford Focus JVC KD-A815 Sony CDX-GT410u Sony XT-100HD HD Tuner Stock speakers, no amp, no subs

  • Don:

    I can see how the diagram may be confusing, so, I thought I'd attempt to offer a little clarity on the point of impedance shown in the diagram.

    I know what TigerHeli means, but, there is no load on each voice coil of the speaker: the speaker is the load (each voice coil presents 4-ohms of resistance) and wired in this configuration (parallel) ultimately presents a 2-ohm load (of resistance) to the amp.

    Clear as mud? Wink

    Ah... thanks Don for making that distinction, it's beginning to dawn on me what this actually means.  I was thinking that the voice coils themselves were the loads.  Sounds like maybe I need to find a speaker theory page so I can understand what's really happening behind the scenes...

  • I was thinking that the voice coils themselves were the loads. 

    Actually, that's correct. Each voice coil represents a separate load that together creates the total load the amp sees. The distinction I was trying to make was that there is no load on the voice coils because they are the load that the amp sees. Sorry for any further confusion.

    These links may help: Matching Subs & amps,  DVCs, Subwoofer FAQs.

    Don
    Community Manager