Building a cab: Have questions about ohmage for speakers

Discussion in 'Amps and Cabs' started by chrisrocksusa, Feb 2, 2012.

  1. chrisrocksusa

    chrisrocksusa Member

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    So I'm building a 2x12 cab, and want to load them with V30s.

    I see that I can order V30s in either 8ohm, or 16 ohms. My amp (mesa rectoverb) has two 4 ohm outputs and 1 8 ohm output.


    I may end up building a second 2x12 cabinet, and would like to run both of them. What ohmage V30 should I go with, so I don't run into trouble later on when I build the second and want to use them both.

    thanks!
     
  2. SteveO

    SteveO Member

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    Get a pair of 16s, run them in parallel for eight ohms. If you build a second cab, do the same. Both cabs @ eight ohms in parallel is four ohms, so use the two four ohm outputs on the amp.
     
  3. chrisrocksusa

    chrisrocksusa Member

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    So for one cab w/ two 16 ohm v30s I would use the 8ohm output?
     
  4. SteveO

    SteveO Member

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    Yes, as long as the two speakers are wired in parallel (which would be eight ohms). 2x12s come from Mesa with sixteen ohm speakers in them.
     
  5. chrisrocksusa

    chrisrocksusa Member

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    Thanks steveO!

    Since I'll be mounting and wiring them myself, how do I know if it's wired in parallel? Do the speakers generally come w instructions?
     
  6. MCK

    MCK Member

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  7. MCK

    MCK Member

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  8. mcdes

    mcdes Member of no importance

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    This is what i would do!
     
  9. chrisrocksusa

    chrisrocksusa Member

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    excellent diagrams, thank you!

    my other question is about the jack plate in the back, where you plug the cable from the amp into.

    I found a website that sells the plate, but what's the name of the metal bracing piece that fits in it? The picture is just a hole
     
  10. freaksho

    freaksho Member

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    call Avatar, or any of the other small cab makers. i'm sure they can tell you what it's called and where to find one.

    anyway i thought the plates just have holes and then you fasten the jack(s) to the plate, no?
     
  11. chrisrocksusa

    chrisrocksusa Member

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    Yeah I'm going to have to call, hopefully they sell those jackplates. I found a site that does but they don't have an actual phone # to call.

    What else is required to wire the speakers to the jackplate?
     
  12. freaksho

    freaksho Member

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    just to be absolutely clear: you wire speakers to the jack. you fasten the jack to the plate. and you screw the plate to the cabinet. you probably know that, but anyway.

    are you asking about all materials and tools? if so:
    - 16 gauge wire. speaker wire from Radio Shack or something is fine. you can go bigger but if it gets too big it won't fit through the slots on the speaker terminal (unless you use quick disconnects)
    - speaker quick disconnects (optional). i personally don't use them, rather solder directly to speaker terminals as advised by some techs (but opinions vary)
    - solder iron (35W is a good all purpose size)
    - solder sucker
    - solder
    - wire cutter/stripper
    - input jack
    - jack plate

    and of course a wrench for the jack (can't remember the size).
     
    Last edited: Feb 2, 2012
  13. meterman

    meterman Member

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    I'd study up and make sure you know what you're doing, if you get it wrong and connect your amp you could do some damage. It's not hard, but it's got to be right. Celestions website has some good clear wiring diagrams. And make sure your solder joints are good.

    good luck!!
     
  14. chrisrocksusa

    chrisrocksusa Member

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    thanks for all the help, gentelmen.

    All the carpentry work is no problem, but I am new to wiring. I'll be sure to have someone take a look at my work before I plug the amp into it :bonk


    I'm very grateful for the wealth of knowledge on this site
     
  15. meterman

    meterman Member

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