Speaker/Sub level calibration? Frequency of test tones?

Discussion in 'Archived Threads 2001-2004' started by jeff lam, Jan 14, 2002.

  1. jeff lam

    jeff lam Screenwriter

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    Jeff Lam
    I was calibrating with VE the other day and it occured to me that when setting the levels of speakers and subs, what if the frequency of the tone(sub especially) is a null or mode frequency in your room? This will throw off the entire calibration level. Why don't they include several tones at different frequencies so you can average the levels?

    EX: You calibrate your sub level to 75dB using VE, the tone is a 40Hz signal. Your room modes a 40Hz tone by 10dB, Now your sub is 10dB too low at every other frequency. This can be a problem.

    What is the LFE test tone anyway? Is it a single frequency, a blend of many frequencies, or a specified standard of all LFE tones?

    Any thoughts on this matter?
     
  2. Tom Vodhanel

    Tom Vodhanel Cinematographer

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    the sub tone is usually a 40-80hz pink noise sample.

    This tends to be wide enough that any nulls/peaks will even out.

    I measured one receiver/processor a while back and it used a 30-60hz tone..can't remember which though.

    TV
     
  3. ColinM

    ColinM Cinematographer

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    Its a mish-mash of 40 - 80. Or something close to that. I think it actually oscillates around a bit, too.

    - CM
     
  4. ColinM

    ColinM Cinematographer

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    Yeah, what Tom said...

    Hate it when that happens!

    I look sooo silly...:b
     

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