Page 1 of 2 12 LastLast
Results 1 to 10 of 13

Thread: ROCKFORD FOSGATE PUNCH 200 Amp w/ 3 Ohm Sub

  1. #1
    Newbie
    Join Date
    Apr 2006
    Location
    Russellville, AR
    Posts
    10

    Cool ROCKFORD FOSGATE PUNCH 200 Amp w/ 3 Ohm Sub

    Ok, I have been out of the car audio area for a while now. Time to get back in. I just bought a JL AUDIO 13TW5-3 sub. It is 3 ohm. I am wanting to use my old school fosgate amp to power it. How can I do this. Its specs are as follows.

    It is only recommended to be stable @ 4 ohms bridged and 2 ohms stereo.

    So I guess I am little confused on if and how I can hook this up. Thanks for your time.

  2. #2
    FLAC
    Join Date
    Jan 2008
    Location
    Dartmouth, MA
    Posts
    916
    You can wire a 1 ohm resistor in series with the subwoofer and run the amplifier in bridged mode.
    My Nearly Complete Car:
    http://www.mp3car.com/vbulletin/show...ed-car-pc.html

    Micro Control Center... Control Your Car Across the Internet
    http://www.mp3car.com/fusion-brain/1...-internet.html

    Website: (It's a work in progress, really. All my projects have taken me from ever really developing it.)
    http://paulfurtado.com/

  3. #3
    Variable Bitrate
    Join Date
    Nov 2007
    Posts
    303
    Where can you find a 200-watt 1-ohm resistor?
    Wouldn't that get a little hot?

  4. #4
    FLAC
    Join Date
    Jan 2008
    Location
    Dartmouth, MA
    Posts
    916
    Quote Originally Posted by NSFW View Post
    Where can you find a 200-watt 1-ohm resistor?
    Wouldn't that get a little hot?
    That's the problem, finding one. If you can find one, then you're good. Otherwise, I believe there are some devices out there that can fix this problem. The issue is that I think they can get a little on the expensive side (around $100) so a new amp might be a better solution. I'll see if I can find one though.
    My Nearly Complete Car:
    http://www.mp3car.com/vbulletin/show...ed-car-pc.html

    Micro Control Center... Control Your Car Across the Internet
    http://www.mp3car.com/fusion-brain/1...-internet.html

    Website: (It's a work in progress, really. All my projects have taken me from ever really developing it.)
    http://paulfurtado.com/

  5. #5
    Newbie
    Join Date
    Apr 2006
    Location
    Russellville, AR
    Posts
    10
    Ok found a 200w 1 ohm resister. So if this amp is briged would I not need a 400w?

  6. #6
    FLAC
    Join Date
    Jan 2008
    Location
    Dartmouth, MA
    Posts
    916
    It should also be noted, that when you add more resistance to a circuit, you decrease the wattage in the circuit.
    Ohm's law says that
    I = V/R where I is current, V is voltage and R is resistance.
    In a series setup, the voltage would drop by adding more resistance and in a parallel setup, the current would drop by adding more voltage. Wattage = voltage x current so either way you're losing power.

    You really are better off with changing the subwoofer or the amplifier.

    If you simply hook this up, assuming you keep the volume down it will work. If you go to loud something will blow, be it the amp or the subwoofer.
    My Nearly Complete Car:
    http://www.mp3car.com/vbulletin/show...ed-car-pc.html

    Micro Control Center... Control Your Car Across the Internet
    http://www.mp3car.com/fusion-brain/1...-internet.html

    Website: (It's a work in progress, really. All my projects have taken me from ever really developing it.)
    http://paulfurtado.com/

  7. #7
    FLAC
    Join Date
    Dec 2008
    Posts
    1,322
    screw the resistor and just hook up the sub straight as bridged. youll have a 3-ohm load on a 4-ohm rated configuration, its pretty close. just watch your amp, if it gets too hot to touch just turn back the gain a little. being a fosgate amp i doubt it will have a problem running bridged at 3 ohm.

  8. #8
    FLAC
    Join Date
    Jan 2008
    Location
    Dartmouth, MA
    Posts
    916
    Oh, you posted while I was typing that last response.
    The resistor should be able to handle a wattage about as high as the peak wattage of the amplifier is.

    Using a resistor, you're going to lose a fourth of the amplifier's power in this setup.
    My Nearly Complete Car:
    http://www.mp3car.com/vbulletin/show...ed-car-pc.html

    Micro Control Center... Control Your Car Across the Internet
    http://www.mp3car.com/fusion-brain/1...-internet.html

    Website: (It's a work in progress, really. All my projects have taken me from ever really developing it.)
    http://paulfurtado.com/

  9. #9
    FLAC
    Join Date
    Dec 2008
    Posts
    1,322
    thats why its just better to skip the resistor and just watch amp temps... most fosgate amps are underrated as well, it might like 3ohm just fine...

  10. #10
    FLAC
    Join Date
    Jan 2008
    Location
    Dartmouth, MA
    Posts
    916
    Yeah, just go it without the resistor at first and if the amp doesn't have any temperature problems, keep it that way. Only go down the resistor route if that doesn't work.
    My Nearly Complete Car:
    http://www.mp3car.com/vbulletin/show...ed-car-pc.html

    Micro Control Center... Control Your Car Across the Internet
    http://www.mp3car.com/fusion-brain/1...-internet.html

    Website: (It's a work in progress, really. All my projects have taken me from ever really developing it.)
    http://paulfurtado.com/

Page 1 of 2 12 LastLast

Similar Threads

  1. Rockford Fosgate amps for sale! Prices Posted
    By 7179michan in forum Classified Archive
    Replies: 4
    Last Post: 09-02-2005, 12:53 PM
  2. Queston conerning stinger 200 amp relay
    By vash in forum General Hardware Discussion
    Replies: 2
    Last Post: 05-25-2004, 10:15 AM
  3. FS: Rockford Fosgate Punch 400S amp
    By SiGmA_X in forum Classified Archive
    Replies: 2
    Last Post: 01-13-2004, 01:29 PM
  4. [FS] Rockford Fosgate Power 551X amplifier
    By osirisdon in forum Classified Archive
    Replies: 0
    Last Post: 11-05-2003, 01:03 AM
  5. Rockford power bd1000 amp, 2 Eclipse amps, FS
    By outragis in forum Classified Archive
    Replies: 1
    Last Post: 01-19-2003, 06:01 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •