Confused about crossover?

Discussion in 'Archived Threads 2001-2004' started by JoelM, Jun 9, 2002.

  1. JoelM

    JoelM Stunt Coordinator

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    Here is the equipment

    Denon2802
    Parasound855
    Parasound2003
    Sampson1000

    I have the Denon set to 80hz crossover and speakers set to small, but during Avia Bass test all my speakers bass goes 80 and below still. Shouldn't it cap it off at 80 and redirect anything below to my 2 SVS25-31CS+'s?
     
  2. Paul_R_M

    Paul_R_M Auditioning

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    Most crossovers are not of the "infinite slope" type. An 80 Hz crossover indicates the point where the signal is -x dB below reference. In a typical home theatre receiver, the crossover is only a second order Butterworth. At this frequency, sound in the high pass section is only -3dB down, plus whatever the box rolloff might be. With Home THX receivers and speakers, the box rollof is also of a second order at 80 Hz. The combined electronic and box rollofs form a second order Linkwitz-Riley crossover (24 dB/octave) so the sound is down -6dB at this frequency.

    Depending on the slope of your receiver and the speaker enclosure rolloff, there will still be some audible output at 80 Hz.
     
  3. Dave Dahl

    Dave Dahl Stunt Coordinator

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    Paul, I am not sure I understood your answer.

    -Dave
     
  4. Dan Hine

    Dan Hine Screenwriter

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    Dave,

    What Paul is saying is that crossovers are not brick walls that cut off frequency response right at the crossover freq. Rather response rolls off. This allows for better blend between drivers within a speaker enclosure and speakers with subwoofers. So no, it won't "cap off" anything below 80hz.


    Regards,

    Dan Hine
     

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