Michael: Here is a link to Bryston. The 10B crossover is available in different versions (only one, the 10B Sub, is aimed toward subwoofer integration.) The 10B is pricey. Last I remember, it was around $1200 US??? http://bryston.ca/crossel.html
Unless you get very good help/information from the maker of your center speaker, I have to be honest and advise against replacing the passive crossover with an active one. If you don't EXACTLY match the characteristics of the original passive crossover section, your speaker will not perform as it was intended.
FWIW, if you must, my suggestion is to bi-wire or passively bi-amp. Both will use the current passive crossover.
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Thanks for the replies. Chuck, I tend to agree and think that passive bi-amping might be the right way to go, if I end up doing it at all.
Active bi-amping (done right) has definite benefits, but as you note, could be deliterious if not set up correctly with the intended speaker.
I have never listened to passive bi-amping myself. I should do this next. What is your opinion about it? Is it effective in an obvious way, like active bi-amping is? Or is it an incremental, subtle improvement?
Michael: In general, passive bi-amping should bring more bass headroom and lower overall distortion at high volume levels.
To my ears, the improvements brought by passive bi-amping are far more subtle than active bi-amping. Active setups have no energy absorbing components (capacitors, inductors or resistors) between the amplifiers and the speaker drivers. IMO, this is what makes the critical active vs. passive difference...
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I use an active car subcrossover for my subwoofer..
It seems to help as DPL sends everything under 100 hertz to my sub and I like to cross it over at 45 hertz.
Nathan