Optimal Load Impedance?

Discussion in 'Amps [BG]' started by radicalwalrus, Feb 11, 2013.


  1. radicalwalrus

    radicalwalrus

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    Hi all! I've been scouring the internet for some time trying to figure this all out but I figured it might be better to speak to some actual humans that know what they're talking about.
    So I'm researching a new head and it says that the optimal load impedance is rated at 600 ohm. But I've never heard of it going over 8 ohm. Is 600 ohm the same as say, 6 ohm? Or is there any kind of conversion?
    I'm just trying to figure out what cabs I need to plug in to this. I'm not exactly up to speed on all of this yet, so sorry if this is a simple problem. I'd just like to be sure so I don't ruin anything!
     
  2. Vince Klortho

    Vince Klortho

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    That seems more like the spec for the DI out of the amp - the low impedance three-pin connector.

    Are you sure that is the optimal load impedence of the speaker output ?
     
  3. radicalwalrus

    radicalwalrus

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    On the technical specifications page it was the only thing related to ohms. But I could still always be wrong.
    It's a TC Electronic RH450 head if that helps with anything. Maybe someone knows about that one specifically?
     
  4. walterw

    walterw Supportive Fender Gold Supporting Member

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    "600 Ohm" is not about speakers, that's for damn sure.

    it must be a reference to the line or DI out.
     
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  6. seanm

    seanm I'd kill for a Nobel Peace Prize! Supporting Member

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    600 ohm is standard XLR.

    Yeah, the TC Electronics RH450 spec page sucks. They say power out 450W (800W min load) but don't specify the minimum load :(

    If you follow the link and get the pdf, the minimum load is 2.66 ohms, kinda useless. So, for most useful applications, the minimum load is 4 ohms.
     
  7. Vince Klortho

    Vince Klortho

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    I wouldn't say that's kind of useless. A load of 2.66 ohms is a 4 ohm and an 8 ohm cabinet in parallel. That is asked about here all the time.
     
  8. 1958Bassman

    1958Bassman

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    Or three 8 Ohm speakers/cabs connected parallel.
     
  9. radicalwalrus

    radicalwalrus

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    On the TC E website it lists different variations of cab sizes that you can plug into it. The one I was thinking about was the 4x10 and the 2x12. Are most cabs that are the same size the same ohm? Like, if I just choose a different brand of 4x10 and 2x12 than the ones TC E sells will it be the same?
     
  10. CL400Peavey

    CL400Peavey Supporting Member

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    If you are interested in the RH450, and TC line of cabs, I would recommend you go with two of the 212's and stack them vertically.
     
  11. radicalwalrus

    radicalwalrus

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    Are the two 212's better than a 4x10 and a 2x12?
     
  12. CL400Peavey

    CL400Peavey Supporting Member

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    Yes.

    Doubling up on matching cabs is always going to be more of a good thing. Mixing cabs can be a crap shoot, and depending on a lot of factors not be a good pairing.
     
  13. HolmeBass

    HolmeBass Supporting Member

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    To answer this more general question, no. In fact some manufacturers will offer a given cab, usually 210s and 212s, in both 4 ohm and 8 ohm versions.

    So you really have to read the jack plate on the cabinet to see what its nominal impedance is (2, 4, 8, or 16 ohms, most common by far for bass are 4 and 8 ohm cabinets).
     

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