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Biamping the Yamaha PB-1

Discussion in 'Amps and Cabs [BG]' started by thumbtrap, Aug 4, 2003.


  1. thumbtrap

    thumbtrap

    Jun 26, 2003
    Most passive cabinets advise 2 octaves of overlap between drivers, but most passive crossovers are 6db or 12db octave.

    I've no idea of the slope on my Yamaha PB-1 crossover, but it does have separately adjustable crossover frequencies for HPF and LPF sections. The drivers I've been looking at for subs all roll off around 200 hz. The three midrange drivers I've been considering run between 1.5 and .7 octaves of overlap. The driver with the highest degree of overlap is the least desirable to me because it'd pretty much need a tweeter.

    I'd like a little more overlap, but how much do I really need with the PB-1?
    Does the ability to overlap the crossovers change any rules of thumb for this preamp?
     
  2. ESP-LTD

    ESP-LTD

    Sep 9, 2001
    Idaho
    I'd "guess" that the PB-1 is probably 18-24db per octave slope. I think much sharper and it would ring, and I can't think of any reason they would make it less. If it was a passive crossover, price of components would be an issue tending towards a sloppy Q but in the preamp I don't think so.

    I don't think it will have much effect on your cabinet design. I don't think Yamaha intended it to be a precision adjustment or it would have better markings. I probably have a small amount of overlap but it's just a few degrees of rotation. It's probably more a matter of how I like to EQ that range than anything magic. I suppose it's possible there are some unusual phase things going on at that point, but it's beyond my hearing and math skills.

    I think the HP/LP filter instead of a crossover is a very cool feature. Yamaha did a great job with this preamp.

    My subs seem to start rolling off at about 200hz and 150-200 sounds best to me as an xo point.