2 heads 1 cab at the same time? Is this possible?

Discussion in 'Amps and Cabs' started by Iliketapping, Jan 23, 2008.

  1. Iliketapping

    Iliketapping Member

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    Well? Me and my other guitarist were thinking about this since I don't have the cash to buy myself my own cab :rolleyes::crazy

    I'm thinking about running either a 90 watt head or a 60 watt head through it and he will probably run a 100 watt head thorugh the cab.

    So what specs does the cab need to have to handle this, or is it even possible at all?

    Thanks!:BEER
     
  2. PRNDL

    PRNDL Member

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    How about a 2x12 cab with one speaker to each head?
     
  3. Iliketapping

    Iliketapping Member

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    Yes maybe, but your still not answering my question, what ohms, watts, mono, stereo does the cab need to have? is it even possible?
     
  4. StompBoxBlues

    StompBoxBlues Member

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    You're not giving enough information to get an answer.
    The ohms depends on the amp. You can't have two heads directly connected to the same speakers. Ever. But I think if the Marshall
    stereo cabinets are completely seperate (someone will have to tell you here if it is so) electrically it might be workable/possible.

    But again, YOU haven't done enough to get the information you want.
    The ohms, watts, all depend on what amps you have, what the amps need to have on output. Both heads would have to be able to handle the same output impedance, because stereo cabs are going to be the same on each side.

    But really...what is the advantage? All your sound is going to be coming out of one box, with just two speakers to each of you, side by side, and for that price I would think you could get either a combo, or a small 2 x 12" cabinet for way less...

    Again, no you cannot run two heads into the same speakers.
     
  5. michael.e

    michael.e Supporting Member

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    yikes, relax guy, he was nice enough to click on your thread and try to help with an option, especially as you said, you have no/little money..

    You want a 4-12 to share, think about it logically.....

    You split the amp in to 2 pairs of speakers, that means you need 2 input jacks.
    You get a pair of 16's, you can run them at 8
    You get a pair of 8's, you can run them at 16 or 4

    How many watts do you need?

    That said, you are going to have two different players and two different amps going in to one box. You run the risk of phasing issues with the amps. One of you is going to have to play your amp with flipped polarity, so the signals do not cancel each other out.
    Moreover, the cab is most likely going to experience all sorts of problems with wierd frequencies from two different sources. It may end up resonating in a not so nice way and sound pretty crappy.

    Not a good idea imo.. Especially if you want a 4-12 just because it looks kewl.
    My advice is to pick up a 1-12 cab for each of you. Keep the signals/tones separate. If you cannot afford it, wait until you can, you are not going to be happy with compromising imo.

    Edit-Like it was said above, you need to do a little more homework...
    Emee
     
  6. frank62

    frank62 Member

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    This is done by using a stereo cab. One amp for each input on the cab. Ever notice big acts with two marshall heads on one 4/12.
     
  7. bluestarbass

    bluestarbass Member

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    These are backups, and even if they are running both heads its not at the same time. Can you cite evidence. Ive run sound and recorded tons of bands and ive never heard anyone running 2 heads into 1 4x12 stereo cab. All the above answers are correct.
     
  8. DC1

    DC1 Member

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    It's a bad idea. Even if you dial in the impedance and wiring issues, without separating the cabinet into 2 different acoustic spaces, the 2 guitars will interfere with each other inside the box. It will likely sound really nasty.

    Save up and buy a second cabinet.

    DC
     
  9. fr8_trane

    fr8_trane Member

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  10. DC1

    DC1 Member

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    I think he wants to play both at the same time. The Headbone is an either/or switcher, for only one guitar.

    DC
     
  11. StompBoxBlues

    StompBoxBlues Member

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    Yup...that's what I got too. Personally, I'll wait to hear if the original poster wants to provide more info or not before trying to help..
     
  12. DC1

    DC1 Member

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    It is fine electrically. NOT fine acoustically. If there are two amps, each driving two of four speakers in the same cabinet, and two different guitars playing through them, each guitar will modulate (move) the other two speakers in the box. They are acoustically coupled. The second guitar's 2 speakers, will have to work against the first 2 to make sound. The second guitar will also modulate the first 2 speakers.

    Basically, it is an audio version of World Wide Wrestling.

    Bad idea. You need separate cabinets. Of course, you could put a baffle in the cabinet and acoustically separate the box into 2 enclosures, but this is likely to cost as much as a used cabinet for the OP.

    DC
     
  13. JZG

    JZG Member

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    A stereo cab will do this, but running two separate guitar players through one cab might not be very desirable. I have a stereo 212 cab that can run 4 or 16 ohms mono (depending on which jack is used), meaning one amp is using both speakers. I can also run two amps, one each into one speaker, at 8 ohms. I can A/B the amps, or use them at the same time. Joe Bonamassa does this with his live rig. He uses a pair of stereo 4 x 12's, with two amps going into each cab. I've read that Sonny Landreth will also use stereo Marshall 4 x 12's for fly gigs.
     
  14. StompBoxBlues

    StompBoxBlues Member

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    YES...that is with a closed back cab (which all 4 x 12"'s I've seen are)...I didn't even think of that. That the air in the cab is somewhat pressurized, being closed back so while one speaker is pushin in (against air pressure as well) the other may be moving out, etc.

    This is just a bad idea all around. Plus, who gets it to practice with?:rolleyes:
     

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