2 separate 1x12 cabs - 8 Ohm each - 16ohm

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by glman, Apr 10, 2008.

  1. glman

    glman Member

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    I'v got 2 speaker cabs each loaded with one 8 ohm speaker
    I need to buy a small box to link the 2 speakers in order to get a series load of 16 Ohms - is there a place that sells such a box ready made?
    I can make it myself but would prefer to get a quality well made one
    advice?
     
  2. Blue Strat

    Blue Strat Member

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    Not sure. I would tend to think that any box you would buy would put the speakers in parallel while you want them in series.
     
  3. glman

    glman Member

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    I could probably get someone to build it in such a way as to connect the speakers in series but it would take some time to do it properly - I'm basically looking for a quick fix solution -
    BTW - thanx for the quote on the RCA 6V6's - I'm still intrested just want to try some cheaper 6V6's to get a feel for what they sound like before I buy yours.
     
  4. rah3

    rah3 Member

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    Glman,

    These boxes are common for sound reinforcement. Call your pro sound supplier to see if they carry them. Some only carry speaker splitters (one in and two outs). These are parallel boxes. It is very easy to make a parallel box into a series box. Most soundmen know how to do the rewiring. You need isolation bushing to make sure the - negative (sleeve) is not common with the casing. You can also do this with ABS plastic case that can be had at an electronics store, sometimes called meter or switch cases.

    The wiring goes like this -

    1) Amp output to 16 ohm muzzle.
    2) Muzzle to box input jack.
    3) Input + positive is wired to the + positive (Tip) of Speaker 1 jack.
    4) Negative - Ring of speaker 1 jack is wired to the + positive of speaker 2 jack.
    5) Negative of speaker 2 jack is wired to - negative of input jack.

    The signal flows from the + positive (Tip) of the input jack through both speakers before returning to the - negative (Sleeve) of the input jack. That is a series speaker connection.

    -RAH3

    -RAH3
     
  5. rah3

    rah3 Member

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    Just to reiterate, you cannot do this with jacks that allow the - negative (sleeve) to be common with the case if it's metal. You need to isolate the sleeve connection on the jack. Very important. if you are going to wire it, best to check it all with an ohm meter for proper signal path and for proper ohm load when the speakers are connected to the box.

    -RAH3
     
  6. doveman

    doveman Member

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    I built one with a box from radio shack. But you need a plastic box ... the jacks can't be mounted so the grounds are on metal. 3 jacks and a plastic box will get you there.
     
  7. glman

    glman Member

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    thanx for the reply but I'm now heading in another direction.
    I'm considering mounting another speaker jack on one of the cabs ( properly and neatly ) and then proceeding to interlink the two 8 ohm speakers in a series configuration for a 16 ohm load - into the amp or 16 ohm muzzle
     
  8. doveman

    doveman Member

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    Be sure to test it ... if your mounting the jacks on a metal plate ... you could have the same problem.
     
  9. rockon1

    rockon1 Member

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    I made a series Y cable exactly for this purpose.bob
     
  10. glman

    glman Member

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  11. Blue Strat

    Blue Strat Member

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    No problem. You'll notice that I have about 10 less expensive 6V6 types on my website.
     
  12. glman

    glman Member

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    i did notice that - but I couldn't see a quad of tung-sol's which is what I wanted - you only had a matched pair.i couldn't select a quad in the options box so I assumed that you were out of stock.
    FWIW - the Tung-sol re-issue 6SL7's that I currently have in my English are working beautifully and are a great alternative to the RCA 5691 - they're obviously not as good but they're pretty close and I kinda prefer them to the RCA 5691 cause they are a bit clearer although not as rich and fat.

    I've ordered a quad of tung-sol 6V6's from doug's tubes but I'm going to get a quad of RCA from you as soon as I've established weather I like 6V6 or not , I just hope they're not all gone by then! - 6V6's just might not be for me -and i don't want to spend $$$ to find out.
    The tung-sol's although not in the same class as the old RCA's will give me a good idea as to weather I like 6V6's or not.
    I appreciate you taking the time to answer all my questions and also the quote you sent me!
    i'm sure we'll be doing business in future.
     
  13. Randy

    Randy Member

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