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How do you determine a cabinets resistance (ohms) ?

Discussion in 'Amps and Cabs [BG]' started by cgworkman, Nov 17, 2004.


  1. cgworkman

    cgworkman

    May 14, 2004
    Ohio
    How do you determine a cabinets resistance (ohms) ? Can I put my multimeter on it, etc? I have a cabinet that was custom built, but the original owner doesn't remember what the cabinet was rated. I'd like to know what the resistance of the cab is. Is it possible to figure this out without dismantling the cab to visually inspect the drivers, etc?

    Thanks in advance
     
  2. NJL

    NJL

    Apr 12, 2002
    San Antonio
    i would think you would have to look at the speakers and how they are wired....i really don't know, but this is a good question

    bump

    :)
     
  3. Passinwind

    Passinwind I Know Nothing Supporting Member

    Yes, you can meter it without taking anything apart. The meter will give you DC resistance, not impedance, but it's close enough. Depending on your meter's lead resistance, expect readings around 6-7 ohms for an 8 ohm cab, and 3+/- for a 4 ohm one.
     
  4. cgworkman

    cgworkman

    May 14, 2004
    Ohio
    OK, at the risk of sounding like an idiot - Do I just place the + and - leads of my meter on the + and - terminals of the cab and set the meter to measure resistance of DC?
     
  5. nonsqtr

    nonsqtr The emperor has no clothes!

    Aug 29, 2003
    Burbank CA USA
    Yes.

    The "ohms" setting on your multi-meter is the one you want. :)
     
  6. Passinwind

    Passinwind I Know Nothing Supporting Member

    Use the lowest ohms range available on the meter too. :cool:
     
  7. cgworkman

    cgworkman

    May 14, 2004
    Ohio
    Yeah - I got the ohms part :)
     
  8. NJL

    NJL

    Apr 12, 2002
    San Antonio
    i hope you're not being rude, these guys are just trying to help you out.
     
  9. cgworkman

    cgworkman

    May 14, 2004
    Ohio
    Not at all. I was told that you had to use a battery to fake a load on the cab. I understand about the ohm setting on my meter :)
     
  10. the only battery required for this test is the one in the ohm meter. just put the probes on the cabinet terminals.meter set to lowest ohms range.
     
  11. cgworkman

    cgworkman

    May 14, 2004
    Ohio
    I was at work when I read and replied to your post there. It didn't really dawn on me until later - Why is it you have to assume things and jump to conclusions??
     
  12. cgworkman

    cgworkman

    May 14, 2004
    Ohio
    That's what I was thinking too. But I read online elsewhere this process required a 9volt battery to work.

    Thanks again.

    :)
     
  13. NJL

    NJL

    Apr 12, 2002
    San Antonio
    because the :rolleyes: that you used in the post you edited seemed like you were kind of jumping on them. that's just what i saw.

    :)
     
  14. cgworkman

    cgworkman

    May 14, 2004
    Ohio
    I'll give you that one. So many times our true emotions are lost at the keyboard.


    :bassist:
     
  15. NJL

    NJL

    Apr 12, 2002
    San Antonio
    that does suck about the internet, maybe we need more emoticons! :D :cool:

    nonetheless, great and informative thread :)
     
  16. Passinwind

    Passinwind I Know Nothing Supporting Member

    FWIW,

    I didn't take anything as being rude, and wasn't trying to diss anyone by oversimplifying. :cool:

    [​IMG]
     
  17. cgworkman

    cgworkman

    May 14, 2004
    Ohio
    :) :cool: :smug: :p ;) :hyper: :D
     
  18. lowb1970

    lowb1970 Supporting Member

    Feb 29, 2004
    Columbia SC
    :bassist: :spit: :hyper: :hyper: :help: :eek: :bassist: :bag:
     
  19. Hey, where´s the bass blayer? :mad:
     
  20. The 9 volt battery would be used to check polarity of the drivers. When you connect and disconnect the battery from the cabinet terminals, all drivers should be moving in the same direction; i.e. either all in or all out. If the drivers are not moving in the same direction, your bass response will totally suck. :bassist: