Hi, I am going to be trying to build my first pair of high end speakers during this next year. I have done a bunch of planning and just bought my first set of drivers, a pair of Bohlender Graebener Neo 8 planar transducers. I would like to mate these with a pair of 6 to 6.5 inch woofers, possibly the Dynavox LW6004 PMR or Morel TiW 634 Ft3 titanium series. I have a number of questions and this will be a long build. I am thinking of going with the Dynavox and one of my first questions is about crossover frequency. The Neo does not really have a resonant frequency and will go down to 200 hz but the company recommends a frequency of 500-800hz. The Dynavox's go up to 5000hz and then drop off. I am wondering rather than crossover at 1 frequency, I can make the crossover frequency at 800hz for the Neo and 3200hz for the cutoff on the woofer. I would use a first order Butterworth and place a Zoebel on the woofer to correct the impedance and an attenuator on the Neo to match the volume. I might also need a notch filter for the Neo but I am not sure yet. I have read where you can do the crossover like this if the drivers will each cover 2 octaves of the other one and these will. If I find I can't do this then I will try to place the crossover point somewhere around 1600hz although it woul be nice to model this better. I am trying to get most of the vocal range to be reproduced by the Neo as I really like that planar sound but would like to get the most out of the woofer. The Dynavox's also only require a small box which is one of the reasons I chose them as I am trying to make these a bookshelf size speaker on the order of a Quad 12L but with that nice planar sound.