Recently JLM has asked a couple of the speaker purveyors, here in the circles, about actively biamping their designs. He received very well thought out and comprehensive relies why they do not implement this method of driving speakers. It reminded me about a back and forth I had with David Ellis some time ago.
http://www.audiocircle.com/index.php?topic=16410.0 I am not ashamed to admit that passive crossovers have come a long way, quality wise, since the time that I had shied away from them years ago. I thought this would be a good time to share some of the conclusions and solutions I have come to.
Its been pointed out that adding an electronic crossover adds a degree of complexity and extra circuitry, not to mention cost, that degrades the sound more than that of a passive power level crossover does. I came to the same conclusion when considering using a Behringer DCX crossover for home use. While a very versatile, and reasonably thrifty, unit the DCX would have required an extensive amount of modding to work in a home situation. It was in a response at DIYaudio forums in a thread about the DCX that planet10, the maker of phase plugs for the Visaton B200 and other drivers, pointed me in the direction of the Marchand XM-46 passive line level crossovers.
http://www.marchandelec.com/xm46.html Like the crossovers used in speakers, these devices require no power and are very simple in operation using a minimum of components. They can be ordered for almost any frequency and slope one would need. Being passive they do have an insertion loss of about 1 db. It was in the context of a subwoofer crossover that I was planning to use the DCX as I had come to the conclusion earlier that placing ANY crossover in the midrange, where the ear is most sensitive, would be as detrimental to the sound as using the passive power level crossover. Toward that end I ordered a pair of the XM-46, 24 db per octave at 70hz, kits and had them sent to Vinnie at Redwine Audio to put together and put in an enclosure. I used these with a pair of Omega Aperiodic 8s and a Onix Rocket UFW-12 subwoofer with outstanding results. As the A8s and UFW-12 are now in storage, I use the XM-46 with my 'portable' system: Genelec 8020s and a Sunfire Super Junior. The Genelecs are powered biamped mini-monitors and, although they use an electronic crossover in the midrange, sound great especially when relieved of the frequencies below 70hz and when the active line level variable high pass filter in the Super Jr. is bypassed. The XM-46 works well even though I'm using a Creek OBH-12 passive attenuator. I guess I'm just a passive kind of guy.
My Redwine modded SB3, with custom opamp, has plenty of voltage to drive the whole shebang.
