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Roll Off ( yep another sub question )

Discussion in 'Subwoofers' started by dUnKle, Jun 11, 2003.

  1. dUnKle

    dUnKle
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    Is there an actual way of finding out EXACTLY what the roll off on a sub should be ?

    For example I use my Rel quake with a pair of B&W 603s - surely there should be something that will tell me what the roll of should be for these speakers
     
  2. Jase

    Jase
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    Check the frequency response. e.g 50hz +/-3db. The specs should be on the websites of each manufacturer.
     
  3. dUnKle

    dUnKle
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    Thanks mate, and I hope this does not come out as rude as its not intended as such, but is there any chance of that in English ?
     
  4. Jase

    Jase
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    Speakers and subs will have a frequency response which shows the lowest frequency they go down to and extending up to the highest frequency. The db rating that you should look for ideally should be +/-3db (or lower like M&K's +/-2db). Some manufacturers "cheat" especially for their subwoofers by quoting figures like 16hz - 150hz +/-10db. It gives the impression that the sub is capable of going lower than it really can. Distortion starts creeping in and you don't want that!
     
  5. Jase

    Jase
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  6. dunkyboy

    dunkyboy
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    Even then, though, it's only ever a very rough guide - room gain comes into play, and can drastically change the frequency response of speakers and subwoofer. Also, the positioning and phase switch of the sub will affect the cancellation/reinforcement of bass sounds between the sub and speakers.

    So you could use B&W's specs as a starting point, but you'll almost certainly have to have a play, and tune it by ear.

    Dunc
     

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