line-level crossover -- design help, please?

[robmonk]

I want to build line-level crossovers so that I can bi-amp my two-way cabinets featuring VIFA 5-1/4" and seas soft-dome tweeters (I don't have my tools, so I can't look at the model numbers just now...). If anyone can point me to basic (tunable) circuit designs and help for calculating the resonance of different resistor/capacitor values, I'd love it.

I've been tinkering with crossover frequencies using a UREI electronic crossover (18db/octave active crossover with independent gain controls per output), and currently find that a crossover-point of 4500 Hz sounds best to me. I've set the hi/lo gain controls fairly similarly, so I'm hoping that I can get away with a fairly simple 'black box' circuit, or at the most, one with a simple hi-frequency attenuator, to match the hi/lo output levels to the drivers' different efficiencies.

I wonder what the consensus is on ideal crossover slope and other characteristics for line-level crossovers feeding a two-way system?

Is there such thing as a passive line-level crossover? Are there considerations of creating mismatch between preamp output inpedence and the amplifiers' input impedence, by inserting a passive circuit?


- Rob

[joensd]

http://www.t-linespeakers.org/tech/f...ssiveHLxo.html

If you don´t mind opamps you could build Rod Elliots 12dB/24dB-Linkwitz-active XO; works great for me.

BTW: The forum has a search function