(2) MCM 2421's

Discussion in 'Home Theater Projects' started by AdamWood, Jan 7, 2004.

  1. AdamWood

    AdamWood Agent

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    Ok, so two of these drivers are on their way and should be here tommarrow. Im am trying to design a box for them with WinISD and have came up with a 1.5cuft box tuned anywhere from 20-30Hz. Which would you say? Both of these drivers are going to be sharing the same airspace and being powered by a 250watt PE amp (getting 180watts beacuse of 8ohms).

    Here is the T/S's:

    Fs-30.4hz, Vas-0.90cuft,
    Qts-0.2109, Qms-11.29, Qes-0.215, Mms-61.2g,
    [email protected], Bl-13.19Tm, [email protected],Re-3.2ohms,
    No-0.324%, Wattage-120w, Sd-201.1sq/cm, Vd-0.24L,
    Rms-1.03kg/s, Cms-0.488mm/N, Xmax-12~16mm

    So I guess my question is where should I tuned this box at? BTW, my amp has been modded to have its bass boast at 22Hz instead of the 30Hz...

    The drivers:
    http://mcm.newark.com/NewarkWebComme...jsp?id=55-2421
     
  2. Allen Ross

    Allen Ross Supporting Actor

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    thats very similar to my MCM 10's that I have
     
  3. ThomasW

    ThomasW Cinematographer

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    To make an informed decision as to the tuning frequency one really should have a FR plot....

    If you don't have a plot and since the Fs is 30Hz, it's probably a good idea to tune close to that. Trying to get any significant output below the Fs is a bad idea when using 8" drivers.

    IMO it's not a good idea to use boost with drivers of this size. It's just WAY too easy to over drive them. One certainly shouldn't be using any 22Hz boost.
     
  4. AllanRW

    AllanRW Second Unit

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    Well good luck with the 2421s.
    I had MCM send me a few to test against the TB W8.
    At first I thought was a no brainer the MCM cost was half at the time of the TB.Which has since dropped in price.
    Anyway the Spyder on the MCM after 4 months of HT use in ported cabinet fell out.
    The Suspension was lost.
    I switched to another MCM 2421 as I said I got a few sent from MCM to test along with the PR they have instock.
    The PR is just a 10" driver with no motor.Nothing special.
    If you use them you will need 4 of them.
    If you go ported be ready for some folded port inside that cabinet.Not that it can not be done I do it using the TB driver now.

    Just look at the driver after a few months.
    I am not sure if they were just from a bad run or what.But all 4 of them I had lost the spyder control.

    Just my 2 cents.

    Al
     
  5. Allen Ross

    Allen Ross Supporting Actor

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    OUCH
     

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