Subwoofer and xover question

Discussion in 'Speakers' started by Arakal, Sep 4, 2003.

  1. Arakal

    Arakal Auditioning

    Aug 31, 2003
    Likes Received:
    I have AM-15 in addition to Deftech BP2006TL which I am using as main L/R. These are connected to Denon AVR-3802. I have an option to run 7.1 channel (at the moment, my 2 satellite cubes are idle). I have used a Y-connector on the sub-out on the AVR with one going to the Bass Module and the other to L/R BP2006TL as they are powered with active sub (250 wts). On my receiver, I have set the LFE settings to LFE+Mains. I have a crossover freq settings option of 80/100/120. Kindly let me know whether my settings makes sense and the correct crossover freq setting that I should adopt? Can Acoustimass Bass Module(active) be counted on to take care of the low frequencies? Can it be treated as equivalent to a Subwoofer? Many threads on this forum does not agree...whereas the bose people call it a "subwoofer". Looking for a clarification on this.[​IMG]

    Thanks [​IMG]

    My Hometheatre:

    Thomsun DTH5000 DVD
    Definitive Technology BP2006TL (Mains)
    Bose Acoustimass 15 (Bass Module + 5 cube speakers)
  2. Lew Crippen

    Lew Crippen Executive Producer

    May 19, 2002
    Likes Received:
    Welcome to the forum Arakal. The reason that many people here don’t consider the Acoutimass Module a subwoofer, is that the limited lower frequency output of the Bose satellite speakers requires the AM do reproduce much higher frequencies that most subwoofers.

    Though Bose does not provide much technical data, the AM appears to reproduce frequencies as high as 250 Hz (or more) significalnty higher than most subwoofers flat output, which is usually something like 20 or 25 Hz–150 Hz. And in most setups, the sub is not expected to go to the top of its range. For example a typical crossover at 80 Hz would probably require the sub to reproduce sounds as high as 100 Hz–120 Hz, but at much smaller sound levels as the frequencies increase (the bulk of the sound going to the main speakers). Even crossing over at 120 Hz won’t require the sub to work too hard in the 150 Hz range.

    Contrast this with the Bose approach where (apparently) the crossover is at 250 Hz. This means that the AM will be called upon to reproduce sounds at full volume, for about another octave and a half, compared to a true sub.

    For me, the requirement on the AM to reproduce a larger range means that it does not do all that well in the first two octaves (20 Hz–80 Hz).

    This seems like an OK temporary solution, but I’m guessing that your DefTech main speakers will do a better job on the LFE channel than the AM. Try setting them to large and the sub to ‘none’ and see how you like that approach.

    In the end, experiment and choose what sounds best to you.

Share This Page