Do most subs have adjustable high-pass crossover for mains?

Discussion in 'Archived Threads 2001-2004' started by ChrisAG, Feb 28, 2002.

  1. ChrisAG

    ChrisAG Supporting Actor

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    Most if not all subs have the ability to accept speaker wire from the amp and then send a signal to the mains, giving you a choice of a full range signal or one that is crossed over at some point. Sould the crossover to the mains be adjustable? What subs have this feature, if any?
     
  2. ChrisAG

    ChrisAG Supporting Actor

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    Bump this up a notch...

    Do any subs have this feature?
     
  3. ling_w

    ling_w Second Unit

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    You can't (shoudn't) have that in a speaker level input of a sub. Since it will be a pass-through, there will be no buffer stage for the crossover, therefore, your main speakers would act as part of the crossover network. And since the mfg don't know the impedence of your speaker at the desired crossover freq, they can't accurately implement a crossover with the desired cutoff freq.

    Any sub's amp that has a filtered output for speaker level is just guessing that the speakers hooked up to it would have an 8ohm impedence at the crossover freq. If your speaker's impedence is 4ohm in that range, the cutoff freq would be at 160hz instead of 80hz, definitely not something one would want.

    Forget about adjustable crossover at the speaker level. If you want to do a fixed or adjustable one, you would have to build it yourself.

    If you want adjustable crossover for mains and sub, you would have to get one that does it at the line-level. Even then, you are limited to a few.
     
  4. ChrisAG

    ChrisAG Supporting Actor

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    But doesn't the Outlaw ICBM do what you are describing? There's no way that product knows what impedence your speakers are.
     
  5. ling_w

    ling_w Second Unit

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    the ICBM does not take speaker level input from amps. It takes line level input from preamps or DVD-A/SACD players. Since it feeds to a power amp or pre/proc instead of to speakers, it does not have to preserve and reproduce the incoming current that would have been fed to a speaker load. What it is driving (power amp) has a high (but unknown) impedence, therefore require only voltage swings. It then could be designed so the crossover network resides behind a buffer stage, which has a high enough impedence relative to the resistor that will determine the crossover freq.

    Basically, all variables are known in a line level crossover.
     
  6. ChrisAG

    ChrisAG Supporting Actor

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    I see, thanks for the info.
     

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