Question for sonosub project.

Discussion in 'Home Theater Projects' started by Chris:-/OV, Oct 18, 2003.

  1. Chris:-/OV

    Chris:-/OV Stunt Coordinator

    Joined:
    Sep 7, 2003
    Messages:
    50
    Likes Received:
    0
    Trophy Points:
    0
    Hi
    I love this forum a I know you guys will be able to give me some advice. I live in South Africa and plate amps can't be bought here funny enough. I can get hold of very good car subs here though but to drive this sub will I be able to use an 8 ohm amp? (The subwoofer is 4ohm) Or can I use a step down transformer and use a car amp to power the sub which will be in a sonosub enclosure?
     
  2. GrahamT

    GrahamT Supporting Actor

    Joined:
    Sep 13, 2003
    Messages:
    556
    Likes Received:
    0
    Trophy Points:
    0
    Leave car stuff alone. Car subs run off 12vdc and home subs run off 120vac or 230vac. Car subs and drivers are designed to be used in small boxes (cars) and are helped by cabin gain. Home subs (often 4 ohms) are usually designed for rooms about 2000 cubic feet in volume. THere is a big difference between them. Try looking at importing a sub from SVS or HSU or building your own from adire or parts express.
     
  3. Anthony_I

    Anthony_I Stunt Coordinator

    Joined:
    Sep 9, 2003
    Messages:
    177
    Likes Received:
    0
    Trophy Points:
    0
    I built a subwoofer using a Phoenix Gold Octane R12d. Since it is a dual voice coil i can run it at 8 Ohms with the voice coils wired in series.

    I also purchased a Rythmik audio plate amp and had the guy custom mod it for me.

    I had to put the woofer in a 3Ft^3 box though, but it does sound good.
    HOWEVER, no doubt you would have better sound from an HT woofer.

    Check out
    www.rythmikaudio.com

    You can buy a plate amp there, it will run at 4 or 8 Ohms.
     
  4. TimForman

    TimForman Supporting Actor

    Joined:
    Dec 4, 2002
    Messages:
    847
    Likes Received:
    0
    Trophy Points:
    0
    Hello Chris,
    When you say you can get good car subs are you referring to drivers or complete systems in enclosures? Per Anthony's suggestion you could wire two 4 ohm drivers in series to provide the 8 ohm load. Car sub drivers are a compromise but if that's what is available you can use them to great satisfaction in the correct set-up. Instead of using a car amp consider using an old stereo receiver or perhaps a pro-audio amp.
     
  5. Chris:-/OV

    Chris:-/OV Stunt Coordinator

    Joined:
    Sep 7, 2003
    Messages:
    50
    Likes Received:
    0
    Trophy Points:
    0
    Hi
    Thanks for your replies. I can get good subwoofers here(just the drivers) and i'll be building the enclosure for it myself using WinISD. How does connecting the subs in series double their ohm's. So does this mean that if a sub has a dual voice coil and it's impedence is 4ohm and you connect both it's connectors in series it will be 8ohm?
     
  6. GrahamT

    GrahamT Supporting Actor

    Joined:
    Sep 13, 2003
    Messages:
    556
    Likes Received:
    0
    Trophy Points:
    0
    I suggest you do some research on the basics of electricity (esp ohm's law) before you start the project. Yes if you connect two VCs that are both 4 ohm each in series properly you will have 8 ohms nominal impedence.
     
  7. TimForman

    TimForman Supporting Actor

    Joined:
    Dec 4, 2002
    Messages:
    847
    Likes Received:
    0
    Trophy Points:
    0

Share This Page