Subwoofer Crossover

Discussion in 'Archived Threads 2001-2004' started by MikeDierbeck, Apr 17, 2002.

  1. MikeDierbeck

    MikeDierbeck Agent

    Apr 15, 2002
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    I've seen some people say that you set the subwoofer crossover to 80Hz. However, I've seen many posts that say you should put ths subwoofer xover at the highest it can go (150-200Hz). Is it just a matter of opinion? Or is there a "correct" answer? I have a JBL Subwoofer, pretty heavy duty one. I have an STRDE975 Receiver with JBL S-Center speaker and JBL Tower speakers.
    Where should I put the Sub crossover at?
    Right now I have the front speakers, center speaker, surround, and sub ALL at 80Hz. I think my receiver can handle 40Hz - 20KHz. My Center speaker has a frequency of 80Hz to 20KHz.
    I asked this question before and seemed to get some different responses, but nothing to definite. I've used AVIA to calibrate everything, and everything SEEMS to run smoothly, except for the dialogue, which sounds LOUD, but like everyboyd has a cold or a nasal problem. could the frequencies be causing this problem or am I just hearing things? [​IMG]
    Thanks for any help
  2. Barry Barnes

    Barry Barnes Stunt Coordinator

    Mar 31, 2002
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    The reason people are saying to turn it up as loud as it will go is because this assumes you are using the 80 Hz Xover built into your HT receiver's dolby digital out. 80 Hz is a good general setting. No need to have two xovers at 80 Hz as this extra slope will simply rob you of some blend and overall output from your sub. I tend to like to cross over my SVS at around 60 Hz for music since they blend better with my mains at that setting. Otherwise for Movies I just let the xover in my receiver handle it and it blends fine. HTH.
  3. RichardMA

    RichardMA Second Unit

    Apr 16, 2002
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    The moment you start to rise above 80hz with the

    subwoofer crossover, you start to "localize" the sub.

    This means you can detect where the sound is coming from.

    Low bass (80hz or lower)has a spherical radiation pattern

    so it's not localizable, meaning the rumblings you hear

    from your sub don't announce it's location to you.

    Some cheap systems (with tiny Bose-type speakers)

    cross the sub over at 200hz or more because the puny speaker's frequency response starts to fall off precipitously at around 250hz or even higher! The result is that things like deep male voices and other low frequency sounds that should be confined to a specific

    channel (like the centre for instance)start coming out of the sub, and you can tell where they are coming from.

    This helps destroy the sound stage and whatever proper placement the director arranged when he did the sound

    for the movie. In other words, if you can avoid it, don't

    cross the sub higher than 80hz to 100hz.

  4. Phil Iturralde

    Phil Iturralde Screenwriter

    Oct 7, 1998
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    If you can, turn-off your JBL Sub x-over & let your Sony handle the 80 Hz x-over.

    If you can't turn-off the JBL Sub x-over, then dial it to it's highest setting so as Barry said the two x-over's won't
  5. jeff lam

    jeff lam Screenwriter

    Jun 4, 2001
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    San Jose, CA
    Real Name:
    Jeff Lam
    The are assuming you are using the receivers built in crossover at 80 Hz. If so, dissable your crossover on your sub/sub amp. If you can't disable it, set it to the highest setting.
  6. Harold_C

    Harold_C Stunt Coordinator

    Apr 1, 2002
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    Use the receiver's crossover for everything. Either disable the crossover on the back of the sub (a bypass switch or a direct input) or turn the crossover on the back of the sub all the way up so it is effectively bypassed.

    On your receiver, use either an 80 Hz or 100 Hz crossover depending on what options your receiver provides. There won't be a lick of audible difference between an 80Hz and 100 Hz crossover. Either would work just fine, assuming the subwoofer levels are set properly.

    I would NOT use a crossover setting below 80 Hz for a Dolby Digital system. This could cause all kinds of problems for the LFE channel, which is recorded with an 80 Hz low pass filter.

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