proper way to use the mono/stereo switch

Discussion in 'Marshall Amps' started by Exotic, Jul 15, 2019.

  1. Exotic

    Exotic Member

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    Hello ,what is the proper way to use the mono/stereo switch on a marshall 1960 vintage 4x12 straight cabinet where the 2 plugs in the back say 1960b 4x12
    150c/ch. stereo
    warning !do not switch to mono with stereo input
    i currently have a marshall jcm 800 100 watt 2210 plugged into a marshall 4x12 avt412 8 ohms 200w rms angled cabinet .
    but i'm looking at a marshall 1960 vintage 4x12 straight cab ,and would like to know how to use just one and possibly both cabinets together in a stack . right now i have head and cab both set to 8 ohms . but need to know the proper settings when bringing in the 1960 vintage to use either separate or together ,thanks .
     

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  2. SmokeyDopey

    SmokeyDopey Well-Known Member VIP Member

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    The 1960B can be used in mono (4 speakers) or stereo 2 speakers separately.

    Set in stereo, you're using 2 speakers at a time on each side, and they would be both 8 ohms. In MONO it can be 4 ohms on one of the jacks, or 16 ohms on the other jack.

    The other 4x12 you have is 8 ohm, so I think you will only be able to use the 1960B in stereo mode (only 2 speakers running) to avoid a mismatch if you want to use both those cabs.

    You would need to use 2 output jacks from the head, and I think it should be set to 4 ohms using both cabs (if you connect 2 8 ohm cabs in parallel, you cut the impedance in half, so to speak).
     
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  3. Dogs of Doom

    Dogs of Doom Moderator Staff Member

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    best bet?

    just use the cab that sounds best...

    What head?
     
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  4. Boxtrot56

    Boxtrot56 Well-Known Member

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    This is a useful post for tgose of us not fully understanding the importance of hooking up cabs - I include myself firmly within that group.
    Although I have worked out how to hook my own 1960AV 412 up to my DSL 100H R, (& that there are different ways of doing so that will be safe) the issue of stereo....just seeing the word makes us want it, I find at least....I am still a way off understanding it totally.
    I do have a secondary 2x12 cab, and really aren't sure if I can weave it in ( with ANY reasonable outcome, of course). Stereo is far from as simple as adding a 2nd cabinet.....I think??!!??
    I do get that running a single 412 can in stereo will split the cab into L and R (vertically).....does this mean only one side......or the other.....will be used and heard? How to obtain a reasonable stereo sound of the type most (uninformed!) people might imagine?
    A useful thread for me, and maybe a few others!!!
     
  5. Mitchell Pearrow

    Mitchell Pearrow Well-Known Member

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    I myself am in the camp that does not trust the (stereo, mono, cabs)
    I prefer the old one input cabs, less confusing, less chance of user error!
    My 2 cents
     
  6. Boxtrot56

    Boxtrot56 Well-Known Member

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    That would get my vote Mitch.....at least until I'm a lot more savvy with it all.
     
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  7. Dogs of Doom

    Dogs of Doom Moderator Staff Member

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    1960 cab...

    mono = 1- 4x12
    stereo = 2- 2x12

    You are cutting the cab in ½ using stereo. If you actually have a stereo amp source, there are advantages to cutting the cab in ½ & running 2 independent 2x12 cab's.

    If you are running mono, there are no advantages to running the cabinet this way. It was not intended to be run this way. It will be like having a cab w/ 2 blown (dead) speakers.

    Marshall made the 1961 cab, which was a 2x12 cabinet, w/ the speakers diagonal, but, the holes for the opposite 2 speakers were never cut into the baffle, so the box is air tight.

    example: Marshall 1961 A cab...

    1961a.png

    some other samples:

    [​IMG]
     
  8. Boxtrot56

    Boxtrot56 Well-Known Member

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    Great information @Dogs of Doom
    Am unsure 're my dsl100hr as to stereo or not....but regardless, the 412 sings out so beautifully in mono....for the moment, I can suspend my curiosity for stereo!
    Am really enjoying the learning of new stuff....thanks man!! :) :)
     
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  9. Lance Chambers

    Lance Chambers Well-Known Member

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    If you are using a Marshall amp then you set the cab to Mono and match the amps output using either the 4 or 16 ohm jacks. Marshall does not make a stereo amp.

    You can set the cab to stereo and use two amps simultaneously with a stereo chorus pedal as your signal input into the amps. One amp left input and one amp right input. Don't overload it! BOOM!
     
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  10. Lance Chambers

    Lance Chambers Well-Known Member

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    Guitar > Stereo Chorus Pedal > Amp-1 (out to left stereo cab input) / Amp-2 (out to right stereo cab input). :band:

    However: If you want to reach the back wall I recommend two full stacks (Zakk Wylde style).
     
    Last edited: Jul 15, 2019
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  11. Dogs of Doom

    Dogs of Doom Moderator Staff Member

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    I have a Marshall "stereo" amp, well, a dual monobloc anyways...
     
  12. Lance Chambers

    Lance Chambers Well-Known Member

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    Yep..............a dual "mono-bloc" will suffice.:cheers:
     
    Last edited: Jul 15, 2019
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  13. Lance Chambers

    Lance Chambers Well-Known Member

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    One JCM800 (4 or 16 ohm output) to the 1960 Lead cab (4 or 16 ohm) mono input and the other output from the amp to the 1960 Vintage cab (4 or 16 ohm) mono input. Match the ohm impedance accordingly.
     
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  14. Exotic

    Exotic Member

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    ok i only have one head so no stereo for now .
    so set the cab to mono , and use either the 4 or 16 ohm settings matching them on the head and the cab ,but which is best? 4 or 16 ohm?
    what is the standard most commonly used settings for a marshall half stack (jcm 800 2210 100 watt head,1960b 300watt cab)?
    and the using both cabs treating each cab as 8 ohm ,setting the amp to 4 ohm makes sense .but i don't like the sound of using 6/8 speakers.
    is there any way to use all 8 speakers? and still avoid damage?
    what is the standard most commonly used settings for a marshall stack ( jcm 800 100 watt 2210 head ,2 marshall 1960 cabs (1960a,1960b)?both with the same mono stereo switches.
     
  15. Exotic

    Exotic Member

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    does everything look ok inside?
     

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  16. Exotic

    Exotic Member

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    please check out my post in the thread what 4x12 cab ? in the speakers and cabinets section
     
  17. Dogs of Doom

    Dogs of Doom Moderator Staff Member

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    in the old days, it was most common to run 2- 8 ohm cab's w/ the amp at 4 ohms.

    more modern, it's generally 2- 16 ohm cab's w/ the amp set to 8 ohm...
     
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  18. Exotic

    Exotic Member

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    that's very straight forward and very simple and very helpful .
    but something is off with the cab i bought today ,i paid $220.00 for it btw ,is that pretty good?
    here's the thing ,the speakers say vintage ,the plate at the bottom left front of the cab says vintage ,but the back plate with the switch doesn't match ,these cabs are supposed to be 280 watts rms and it is supposed to read 1960bv ,but it reads 300 watts rms 1960b , which is on 1960 lead cabs right? so is it safe to say that at some point the back plate was swapped out ?
    and ok setting for half stack is easy .but if i want to use both cabs ,i get conflicting stories on the net . one says using a 16 ohm and an 8 ohm and setting the head to either 4 or 8 ohms is fine ,and another says ,solid state maybe but tube amps need to match exactly ,which is it?
     
  19. Exotic

    Exotic Member

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    front plate
     

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  20. Exotic

    Exotic Member

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    non matching back plate?
     

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