Are there any processors or recievers with bass management that uses a 4th order C/O?

Discussion in 'Archived Threads 2001-2004' started by Dustin B, Aug 1, 2002.

  1. Dustin B

    Dustin B Producer

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    There are lots that use 12db in both directions. Some that use 24dB low pass and 12dB high pass (THX certified) that rely on the speaker having a 12dB/octave roll off starting at 80hz. Some like the B&K that allow you to choose 12dB or 24dB for the low pass and 6dB or 12dB for the high pass.

    Even the Outlaw ICBM is only 2nd order except for a special low pass which can be 6th order. But why would you want to mix 2nd and 6th order filters?

    Is a 2nd order crossover steep enough to prevent too much above 100hz output from the sub. Is there some problem with using a 4th order crossover for bass management?
     
  2. Dustin B

    Dustin B Producer

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    I guess no one else knows of one either or why they don't use 4th order crossovers for the bass management.
     
  3. Michael Mohrmann

    Michael Mohrmann Screenwriter

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    "Are there any processors or recievers with bass management that uses a 4th order C/O?"

    Yes, the Lexicon MC-12 and MC-12B have 4th order, 24dB/octave low pass and high pass filters. In addition, they have THX-specified 2nd order, 12dB/octave low pass and high pass filter options @ 80Hz (in addition to the 24dB/octave option at 80Hz).

    Michael
     
  4. JoeyT

    JoeyT Stunt Coordinator

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    Yes. In addition to the lexicon, the EAD Theatermaster products do too.
     
  5. Lewis Besze

    Lewis Besze Producer

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    Dustin,
    it is strictly a design choice IMO.THX certify the 12/24 configuration as you mention it,but the speakers they typically certify, has it's own roll off below 80hz with another 12db/oct "filters",which might give you[more/less] the same thing as the 24db/o filter.
    Interestingly the Denon 5700 used a 1st order filter on it's HP section but it still got the THX moniker, go figure.
    All in all those processors that allow filters to be changed are gets the job done better since it's impossible to predict all the different room/speaker combo's "behavior".
     
  6. Arthur S

    Arthur S Cinematographer

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    Dustin

    I believe the Theta Cassanova allows you to choose the order of the crossovers. Check it out.

    Artie
     
  7. Dustin B

    Dustin B Producer

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    Wow, even used all of those cost an arm and a leg. I guess I'll have to look into making sure whatever speakers I end up building next have a 2nd order roll off starting at 80hz.
     

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