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How to run Acme B4 and Crest CA-9?

Discussion in 'Amps and Cabs [BG]' started by mrpackerguy, Nov 7, 2006.


  1. mrpackerguy

    mrpackerguy Supporting Member

    Jul 3, 2004
    Madison, Wisconsin
    I'm getting an 8ohm B4 can tomorrow. For those of you running a B4, how would you suggest running the B4 with my Crest CA-9? Stereo and 600W or bridged mono and 1800W?
     
  2. BillyB_from_LZ

    BillyB_from_LZ

    Sep 7, 2000
    Chicago
    Bridged!!!

    New or used Acme? If new, be sure to break it in properly before playing loud our you'll probably regret it...
     
  3. alexclaber

    alexclaber Commercial User

    Jun 19, 2001
    Brighton, UK
    Director - Barefaced Ltd
    Bridged!

    The Acmes sound so clean when they're running within their limits that the break-up you get when pushing them too hard is pretty obvious. If that happens, turn down or reduce the lows.

    After years of playing through Acmes I've concluded the 'best' sound comes from minimal EQ (particularly avoiding boost down in the 40Hz area - they simply don't need it unlike most other bass cabs) and plenty of power.

    I've spent quite a while recently trying to come up with some better cab designs and despite the progress in driver technology over the last decade I'm really struggling...

    Alex
     
  4. mrpackerguy

    mrpackerguy Supporting Member

    Jul 3, 2004
    Madison, Wisconsin
    Thanks. I'm getting a B4 series I cabinet that was retrofitted recently by Andy Lewis with series II speakers and crossover.

    In the past I've ran two Acme B2 series II cabs in parallel, but got tired of hauling two speaker cabs around.

    What's the biggest danger of running that much juice into the B4? EQ'ing with too many lows? Running the CA-9 gain too high? In between my basses and the CA-9 is my Kern pre.
     
  5. alexclaber

    alexclaber Commercial User

    Jun 19, 2001
    Brighton, UK
    Director - Barefaced Ltd
    Bass boost is the risk. But you can hear the speakers complain long before damage occurs. With your EQ flat I doubt even the CA9 can take the Acmes to the limit without clipping occasionally.

    Don't believe the myth that the gain knobs on the CA9 control the power output, and thus turning them down will either protect your speakers from too much power or restrict your headroom.

    I keep the gain knobs at about 12 o'clock unless I need more gain - the risk of too much gain late on in the chain is that any extraneous switch on etc noises will come out very loud!

    Alex
     
  6. BillyB_from_LZ

    BillyB_from_LZ

    Sep 7, 2000
    Chicago
    Acme woofers like to M-O-V-E and if driven too hard, the cones will crease. That's why I asked about new vs. used.

    New woofers must be broken in gently to loosen up the surrounds. Otherwise, you run the risk of the voice coil moving farther than the suspension wants to and the cones will crease resulting in a need for new woofers.
     
  7. weeks82

    weeks82

    Oct 10, 2001

    I can attest to this. Even after i broke the speakers in (or so i thought) I creased 2. I still blame the drummer.
     
  8. Lonnybass

    Lonnybass

    Jul 19, 2000
    San Diego
    Endorsing Artist: Pedulla Basses
    Oh yeah? I creased 16 :crying:

    Lonnybass
     
  9. mrpackerguy

    mrpackerguy Supporting Member

    Jul 3, 2004
    Madison, Wisconsin
    The answer is I'm not sure until I see the documentation that accompanies the cabinet. The seller said he used it in his studio so I suspect they are broken in, but I will be practicing several times a week at lower volumes until my next gig in December.
     
  10. BillyB_from_LZ

    BillyB_from_LZ

    Sep 7, 2000
    Chicago
    Good grief...I didn't realize that you replaced them four times!!! Probably from playing those Kiss songs;)
     
  11. weeks82

    weeks82

    Oct 10, 2001

    I guess I can't complain.
     
  12. alexclaber

    alexclaber Commercial User

    Jun 19, 2001
    Brighton, UK
    Director - Barefaced Ltd
    But how?!! After you'd creased 12 did you not think of turning down the lows?!

    Alex
     
  13. arbitrary

    arbitrary Supporting Member

    Oct 24, 2005
    Boston, MA
    mmmm.....ca 9.


    How do you know if you've "creased" your speakers?And what is this "creasing" you speak of?
     
  14. el_Kabong

    el_Kabong

    Jul 11, 2005
    What were you driving it with Lonny?
     
  15. Folmeister

    Folmeister Knowledge is Good - Emile Faber Supporting Member

    May 7, 2003
    Tomball, Texas
    When you look at the speaker, there are ridges on the cone that look like a crease/soft tear in the fabric. Kind of like ring-around-the-collar for speakers. I have replaced only two in my B2. I got a lot of catching up to do!
     

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