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4 x 12 wiring ?

Discussion in 'Amps and Cabs [BG]' started by fretno, Apr 20, 2017.


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  1. fretno

    fretno Supporting Member

    May 10, 2009
    Los Angeles
  2. blubass

    blubass

    Aug 3, 2007
    Modesto Ca
    Current or previous endorsements with: GK, DR Strings, Rotosound, EB, EMG, Dean, Dava Picks, Rebel Straps, Dickies
    A Marshall.... guitar cab, bass cab, Taxi cab?
     
    Lobster11 likes this.
  3. fretno

    fretno Supporting Member

    May 10, 2009
    Los Angeles
    vintage Marshall 4 x 12 slant "guitar" cab
     
  4. blubass

    blubass

    Aug 3, 2007
    Modesto Ca
    Current or previous endorsements with: GK, DR Strings, Rotosound, EB, EMG, Dean, Dava Picks, Rebel Straps, Dickies
    Aside from possibly wasting your money on bass speakers inside a cabinet without the proper dimensions or volume.... there's this link that should help: http://www.usspeaker.com/speaker wiring-1.htm

    You'd be much better off buying a box suited for those speakers, or building one to suit those speakers. Using the marshall cab could be the best sounding bass cab ever.... but realistically you're much more likely to have wasted some money.
     
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  5. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008
    How it is wired depends on the impedance of your amp. The cab can be wired for 2 ohms, 32 ohms, or 8 ohms.
     
  6. fretno

    fretno Supporting Member

    May 10, 2009
    Los Angeles
    The amp is switchable 16,8 or 4 , so it's looking like 8 ohms would be best but there seem to be a few wiring choices all with the same load. Any preference on that ? @ blubass I've used 4x12 on and off over the years . I like them \m/ it's true but I think those drivers will get the job done . Better than say vintage 30s for bass guitar
     
  7. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008
    Eight ohms requires a series parallel combination.

    OPTION 1: two speakers wired in series, connected in parallel with the other two speakers in series.

    OPTION 2: two speakers in wired parallel, connected in series with the other two speakers wired in parallel.

    Both yield eight ohms total if all the speakers have a nominal impedance of 8 ohms.

    I prefer all the speakers connected in parallel. In this case using 32 ohm speakers connected in parallel to yield 8 ohms. That isn't always possible in the real world.
     
    Last edited: Apr 20, 2017
  8. fretno

    fretno Supporting Member

    May 10, 2009
    Los Angeles
    do you have a preference with those wiring choices ? Is the bass response better with one or the other or some other sonic qualities better or worse ? Thanks again
     
  9. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008
    Some people do argue that sonically one is better than the other. Others will argue that they sound the same. The only way to tell is to try both and listen for a preference.

    Another consideration when deciding on the wiring is what happens when one speaker coil blows open. In the first case, the cab will revert to 16 ohms. The power handling capacity will be cut in half. In the latter case, 12 ohms. For a tube amp, a mismatch with 12 ohms is better than the higher 16 ohms; for a solid state amp, 12 ohms will provide less of a drop in power output.

    Always tradeoffs.
     
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  10. fretno

    fretno Supporting Member

    May 10, 2009
    Los Angeles
    Now we are getting somewhere Thank you ! ok so the latter case is called "parallel / series " ? I'll track down a diagram Thanks again
     
  11. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008
    Try looking under that term but combination wirings usually fall under the series parallel heading.

    Look up Marshall 412 cabinet wiring as a general reference. Typically the first approach.


    This site covers a number of wirings: Wiring a 4 X 12 Speaker cabinet
     
    Last edited: Apr 20, 2017
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  12. Killed_by_Death

    Killed_by_Death Snaggletooth

    Jan 2, 2015
    heart of darkness
    attachment.
     
  13. fretno

    fretno Supporting Member

    May 10, 2009
    Los Angeles
    Killed_by_Death likes this.
  14. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008

    This is confusing, both seem to be series parallel. There is a host of different 412 wiring schemes, some are used if there are two pairs of different speakers all the same impedance.
     
  15. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008
    These are the two types of wiring that I was referring to.

    Assume that a speaker has two terminals represented as ([+] [-]) .
    Two speakers wired in series: jack tip-------([+] [-])------([+] [-])------jack sleeve. The outer terminal connect to the ¼" jack, the inner [-] and [+] terminals are connected.
    With a parallel connection, the two outer [+] terminals are connected, the two outer [-] terminals are connected.

    Series-Parallel: This is option 1 in my post above. There are two pairs of series connected speakers, wired in parallel.
    series-parallel.




    What I'll call Parallel-Series-Parallel connection: This is option 2 in my post above. One parallel pair of speakers connected in series to another.
    paralle-series-parallel.


    There are two parallel connected jacks in these illustrations. This allows daisy chaining the cabs. The negative terminal connections of the speakers is not shown.

    The standard that is used is: [+] goes to ¼" tip, [-] goes to ¼" sleeve.
     
  16. Lobster11

    Lobster11 Supporting Member Supporting Member

    Apr 22, 2006
    Williamsburg, VA
    I claim no personal experience or expertise on this subject, but if there is one thing I've learned from reading dozens of similar threads on TB over the years, it's that you can't just stick any speakers in any box and expect it to sound good. How you wire it isn't the issue.
     
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  17. fretno

    fretno Supporting Member

    May 10, 2009
    Los Angeles
    Let's Worry about tone in a different thread :)
     
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  18. fretno

    fretno Supporting Member

    May 10, 2009
    Los Angeles
    Thank you Sir , I'll study this and look into it some more. Cheers
     
    beans-on-toast likes this.
  19. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008
    Let us know how it goes and feel free to ask questions. I recall seeing a good video on youtube where they were changing out the speakers in a 412. You have to be careful to not over tighten the speaker fasteners. They have to be tightened evenly. It's all more complicated than one would think.

    Of course, an amp tech can handle all this for you if you prefer.
     
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  20. fretno

    fretno Supporting Member

    May 10, 2009
    Los Angeles
    first thing I'm going to do is open this thing up and see what it has . I'll have time to dink around with it on the weekend . it currently has Weber Alnico 50 bluedogs in it and I bet I'd blow those fast with a bass guitar . I'll post some pics this week end . Thanks all ! Cheers
     
    Last edited: Apr 20, 2017
    beans-on-toast likes this.