Matching the babies and to stack hi or low???

Discussion in 'Amps and Cabs [BG]' started by FenderMeBass, Nov 5, 2017.


  1. Hey guys, need some advice.

    Firstly I love my 2 Aggie 112's. I stack them usually like so. I use wood to give some space and level between the cabs and the head. Not really a hassle, and I dunno, some bit of me loves getting wood involved lol. Am I breaking a rule by doing this? I know cabinets are made with sonic delivery in mind but would how I stack them make much difference? Thoughts?

    Also with this gear list tell me what you would pair up for a 90's cover band.

    Epifani T210 (400W 4 ohms)
    Aggie GS and DB 112 (300 W 8 ohms)
    Mesa walkabout 300 ( 300 W 4 ohms )
    Promethean 300H (300W 4 ohms)
    Tec Amp Puma 500 ( 500 W 4 ohm )

    Best
    Joe Soup
     

    Attached Files:

  2. BadExample

    BadExample

    Jan 21, 2016
    Injiana
    What could be wrong with getting wood for your aggies?

    TB recommends the vertical stack. You might try flipping the bottom one over 180 degrees so it's still vertical. This would be to get the 12's closer together for acoustic coupling. They might be just a bit far apart as shown.

    It looks like there is a mid or tweeter on the bottom cab and not the top? If that is how it appears, and if you want a brighter sound, put that one on top, "right side up", and the other on bottom, "upside down."

    No rules broken IMO if it works for you. But it's always good to seek improvement.
     
    FenderB likes this.
  3. +1 this ^

    Then flip the logo on one you turned upside down, to remember your new found config.
    Both logo will look like they do now with the new stacking.
    That is if that's a thing for you. It would be a thing for me. :whistle:
     
  4. Paulabass

    Paulabass

    Sep 18, 2017
    Low frequencies will couple as long as they are less than 1/2 of the wavelength apart. A 40hz tone's wavelenght is 28', so the drivers will couple anywhere closer than 14' apart, 7' at 80hz. etc. Having the drivers on the same plane (as in properly stacked back to front) effects phase, and is of far more importance. The tweeters will never couple, like they do in a p.a. line array, because they would need to touch.
     
    Pbassmanca likes this.
  5. BadExample

    BadExample

    Jan 21, 2016
    Injiana
    By this, you are saying the front of the drivers should be lined up on a vertical plane, like they would be if were mounted on a single baffle?
     
  6. Paulabass

    Paulabass

    Sep 18, 2017
    Absolutely. They would only be in phase once every wavelength. On a single baffle they would be in phase, and at 40hz. they would be in phase 28' further forward or back. Phase is never perfect, but at lower frequencies, phase discrepancies are more noticeable.
     
  7. So, what's the verdict here? Horizontal stacking (like not shown) or Vertical stacking with aid of wood separators (like shown) ?
     
    Pbassmanca likes this.
  8. Paulabass

    Paulabass

    Sep 18, 2017
    Performance wise there is no difference. I like a tall stack to get closer to ear level.
     
    Pbassmanca, Ampslut and FenderMeBass like this.
  9. Any thoughts on which amp I should use to power them? I was thinking the Puma.
     
    bassbooty likes this.
  10. I vote vertical. It puts one cabinet closer to your ear and puts the amp and it's controls closer to eye level.

    Mugre
     
  11. seamonkey

    seamonkey

    Aug 6, 2004
    Vertical stack to get the mid highs to your ear level, and turn the tweeter off on the lower cab to prevent high frequency combing out in the audience.

    One tweeter is usually enough for any bass rig.
     
  12. Not following you here, unless I am and I just don't know it.

    If two identical drivers are mounted so they are in the same vertical plane, as in mounted to the same baffle, and they are in phase, wouldn't they always be in phase no matter the distance from the drivers?

    If you had two drivers operating at 40Hz, with one driver 28 feet behind the other, they would also be in phase, right?

    Or are we just saying the same thing two different ways?

    My vote...
    Vertical stack. Gets a driver closer to your ears.
     
  13. ThinCrappyTone

    ThinCrappyTone Guest

    Oct 1, 2011
    gold like this is what I come to TB for
     
  14. < 1/4 wavelength for good coupling.
    A 1/2 wavelength gives a mighty cancelation at 90deg off axis.
     
  15. BadExample

    BadExample

    Jan 21, 2016
    Injiana
    I don't know enough about how the coupling works to do more than echo what I've read. I do seem to recall @agedhorse saying either 1 driver diameter apart or 1/2 driver diameter apart is what you need. Don't hold me to that, might be a false memory. I think that was regarding 10's, if that makes any difference.

    That being said, it seems you would want to couple the all important midbass and mids, in addition to deeper bass freqs. It costs nothing to flip the bottom cab over and try it.
    Absolutely! There is little we can do about phase once the room has it's way with it. Assuming the rig has everything in phase, about all you can do is fiddle with placement and position. Aim carefully :D If there's time, and in a nasty room, a bit of experimentation can go a long ways. I have a really rotten room to play in, but luckily, it doesn't change much because it's the only place I play... my living room :D
     
  16. I'll try throwing the GS on it's side. Dunno how I'll like it aesthetically. Come on guys! No one mentioned anything bout pairing with the shown amps!
     
  17. BadExample

    BadExample

    Jan 21, 2016
    Injiana
    Keep 'em vertical, just turn the bottom one over from where it sits so the 15's are closer. If you have them, just try both amps.
     
  18. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    If you are using wavelength, you will see cancellations well before 1/4-wavelength. Since wavelength varies inversely proportional to frequency, this quickly becomes a moving target. 1/4 wavelength is 90 degrees (in polar representation), which will knock the coupling down by 1/3-1/2 of theoretical maximum.

    This is why in pro audio, we will sometimes choose a block configuration when stacking subs, but other times we might choose a linear configuration. By using the distance between elements in the spacing of the drivers, we can sometimes alter the pattern in a way that is beneficial (assuming enough drivers to do the job plus a little bit more which supply the subtracted energy). A 4 x 4 block of drivers will be more coherent than 16 drivers laid out in a row, but with the row spacing, we can take advantage of the spacing (and usually delay these days) to reduce energy that acoustically wraps around to the back at the lowest frequencies. This generally only makes sense in larger venues and outdoors, where there's plenty of sub capacity.
     
  19. ok, 1/4 wavelength for passable coupling, less is better.

    If we're talking about rooom carrying bass cab stacks, vertical single column for the win.
     
  20. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa, Product Support-Genz Benz
    Or not.

    Without knowing the characteristics of the room or space, this is nothing but a guess.

    Sometimes, the benefit of boundary coupling to the floor with say 4 x 15's might outweigh stacking 4 vertically... especially outside if the speakers must carry the space. Sometimes a block of 4 works better.

    One potentially big disadvantage to a vertical stack, especially short in a wide space, is that you may not get the horizontal coverage you need stacked vertically, plus the additional height will add reflections and comb filtering where difference in path lengths cause reflections off of the boundary are large relative to wavelength. Experience shows that this is often in the 250-1000Hz range where comb filtering (with vertical stacking) can become an issue.

    The boundaries are the other elephant in the room. Without considering boundary interaction, everything is simply a guess.
     
  21. Primary

    Primary TB Assistant

    Here are some related products that TB members are talking about. Clicking on a product will take you to TB’s partner, Primary, where you can find links to TB discussions about these products.

     
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