2x12 cab wiring/switchable ohms question

Discussion in 'Amps and Cabs' started by TubeStack, Dec 27, 2009.

  1. TubeStack

    TubeStack Supporting Member

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    If a 2x12 cab can operate at either 4 ohms or 16 ohms (via a separate input jack for each), this means the two speakers in the cab must be 8 ohm speakers, correct?

    If so, what happens if you replace those 8 ohm speakers with 16 ohm speakers? What is the resulting ohms of the two (formerly 4 & 16 ohm) jacks? 8 and 32 ohms?

    Also, according to http://www.colomar.com/Shavano/2x12wiring.html, only 8 ohm speakers are desired for this sort of a setup, that "no other impedance speaker is recommended for this configuration," but the site doesn't explain why.

    Anyone know?

    Thanks!
     
  2. CaptainJake

    CaptainJake Member

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  3. michael patrick

    michael patrick Supporting Member

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    Because there aren't any guitar amps that run at 32 ohms.
     
  4. TubeStack

    TubeStack Supporting Member

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    Gotcha, makes sense - just wanted to be sure the 16 ohm speakers wouldn't cause some problem/extra-strain on the head. I'll have the 8 ohm out, which will be use-able.

    Reason I ask is I'm probably picking up a series/parallel switching 2x12 and have a bunch of 16 ohm speakers kicking around that I'd like to swap into it.

    Thanks!
     
  5. blackba

    blackba Supporting Member

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    Just run the 16ohm speakers in the parallel wiring jack (will say 4ohms), but with 16ohm speakers it will be 8ohms.
     
  6. MetalGuitard

    MetalGuitard Member

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    TubeStack, I had the same issue with a 2x12 I acquired. I pulled the 8 Ohm speakers out and put 16 Ohm speakers in. Just make sure you label the 8 Ohm Jack 8 Ohm. I don't use the cab that often so I forgot on occasion and being a little rusty with my speaker math wound up plugging into the 32 Ohm jack. Not the worst thing you can do to an amp but still...

    I'll replace the whole jack plate eventually and have only the one jack labeled 8 Ohm. It gets confusing sometimes when you've got a jack plate with 3 plugs <and> a switch all labeled 8 Ohm Stereo / 16 Ohm Mono / 4 Ohm Mono yet you know that none of those apply to how you actually have it wired up and you can't remember which jack = what Ohmage.
     

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