Results 1 to 13 of 13

Thread: Question about new 2x12 set up with 2 Channel H

  1. #1
    Junior Member
    Join Date
    Apr 2014
    Posts
    4

    Question about new 2x12 set up with 2 Channel H

    Hello all!

    New to this forum, and I just had a newbie question about my 2 Channel H head.

    I've been running it through a 4x12 cabinet, but am planning on switching to 2x12s instead.

    Would I route cables from both the SPKR OUT and EXT, one to each 2x12?
    And if this is the case, does the Impedance Selector regulate the impedance output for both of these output jacks?

    Thanks for your responses!

    - Andrew

  2. #2
    Senior Member
    Join Date
    Jan 2014
    Posts
    212
    Andrew are you going to run 1 2/12 or two 2/12s

  3. #3
    Junior Member
    Join Date
    Apr 2014
    Posts
    4
    I want to run two 2x12s at once.

  4. #4
    Senior Member
    Join Date
    Jan 2014
    Posts
    212
    Ok assuming they are both 8 ohms you could plug 1into speaker out and the other into ext out and put switch to 16 ohms.Or you could use a y cord from speaker out to both cabs and leave switch at 16 ohms.

  5. #5
    Member dsenoj's Avatar
    Join Date
    Aug 2012
    Location
    Winston-Salem, NC
    Posts
    105
    With 2 cabinets in parallel that are 8 ohms each, your switch should be set to 4 ohms.

  6. #6
    Junior Member
    Join Date
    Apr 2014
    Posts
    4
    Okay, thanks for the responses!

    Now using the Speaker out and the Ext out, does that wire my two cabs in parallel?

  7. #7
    SuperD Boogie's Avatar
    Join Date
    Apr 2012
    Location
    Indy, IN
    Posts
    1,275
    It's simple, plug the 8 ohm cabs into the 8 ohm outputs on he amp. No second-guessing required. If you have the impedance selector switch, you select 8ohm. The switch will connect your cabs in parallel and to the proper transformer tap. And if you set the wrong setting, nothing bad will happen. In fact, you may find a mismatch to sound better. Give it a try.
    Last edited by Boogie; 04-03-2014 at 06:17 AM.
    + '01 Custom 24 + '11 DGT Standard (Mr. Clean) + '09 SE One + Super Dallas + Stealth 2x12+

  8. #8
    Member dsenoj's Avatar
    Join Date
    Aug 2012
    Location
    Winston-Salem, NC
    Posts
    105
    The speaker out and ext out jacks are parallel. You can see the 2 channel H manual online at http://www.prsguitars.com/csc/manual...nersManual.pdf. They mention using two 8 ohm cabinets in the manual.

  9. #9
    Junior Member
    Join Date
    Apr 2014
    Posts
    4
    Ah okay perfect!

    I was having trouble reading the manual online, it wouldn't show the second page, but after I downloaded it and opened it on my desktop, the whole thing read fine.

    Thanks so much for your responses!

  10. #10
    SuperD Boogie's Avatar
    Join Date
    Apr 2012
    Location
    Indy, IN
    Posts
    1,275
    The important thing is to remember that you don't have to do any math. Read the label on your cab(s). If it says 16ohms, then select 16 ohms setting with the impedance switch. Use the same impedance cabs (all 4/8/16). So, even though you might have two 16 ohm cabs, just plug them in and select 16 ohms. The math is calculated for you on the inside.
    + '01 Custom 24 + '11 DGT Standard (Mr. Clean) + '09 SE One + Super Dallas + Stealth 2x12+

  11. #11
    Senior Member
    Join Date
    Apr 2012
    Posts
    355
    Quote Originally Posted by Boogie View Post
    The important thing is to remember that you don't have to do any math. Read the label on your cab(s). If it says 16ohms, then select 16 ohms setting with the impedance switch. Use the same impedance cabs (all 4/8/16). So, even though you might have two 16 ohm cabs, just plug them in and select 16 ohms. The math is calculated for you on the inside.
    Hey Boogie... In this case, I think that they really do want you to do the math. So, if you're hooking up two 16 Ohm cabs, you set the selector to 8 Ohms. There are counter examples with other amps, but in this case, they want you to compute the combined impedance of the two cabs yourself and set the selector accordingly. At least that's what they say in the manual (and it's sort of the industry standard also...) Problem is, when the jacks are hooked up in parallel like they are here, the amp would have no way of knowing if you have one or two cabs hooked up. It'd just know the combined effective impedance it sees.

  12. #12
    Boogie, I'm no scientist, but I think Aristotle is right.

    This kind of thing can definitely get confusing!
    Check us out: http://www.elfxi.com

  13. #13
    SuperD Boogie's Avatar
    Join Date
    Apr 2012
    Location
    Indy, IN
    Posts
    1,275
    Actually, for the models with a switch, you're probably right. Those with discrete 4/8/16 ohm outputs, are probably exempt. Using an old Twin II schematic for reference (it's what I have handy) there's an elaborate series/parallel switching scheme that combines two 8ohm in parallel and connects to the 4ohm tap and 2-8 ohm outputs connect in series and also use the 4 ohm tap. Only a single 4 ohm output uses the 4ohm tap. This is very typical. Mesa/Boogie is similar in that on old Mark series, there's really only an 8 ohm tap on the transformer and the 2-4 ohm outputs are really in series. The amount of confusion by the general public is HUGE. Without schematics to confirm - or someone taking good gut shots - we can't know for sure.

    My bad guys. I didn't mean to lead anyone down the wrong path.
    Last edited by Boogie; 04-06-2014 at 02:39 PM.
    + '01 Custom 24 + '11 DGT Standard (Mr. Clean) + '09 SE One + Super Dallas + Stealth 2x12+

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •