Hello. I knew Brian and John Casler, probably Brian's biggest fan and one of his top dealers. I also produce a planar line of speakers. So I'm familiar with many of these issues first hand. I think we all know of another unnamed person very critical of Brian. As for Dragoslav, there are really just a few guys on the planet that have the patents for these planar devices. Truly a pain. There are knockoffs out of China - just the QC sucks. B&G from PE do a great job - but upgrading is always a challenge - first for fitment, and then the crossover is a start over - nothing is a true direct replacement - unless the exact same part. And even then, when I replace a mid woofer etc, I replace it in both speakers.
As you are an audiophile, you should start with the room before applying corrections to the speaker. If you have a significant other - they already tolerate you, or have left you - so why not treat the room
Simple 12 x 12 x 2 acoustic pads are great for a wide range. I have one room with 50% of the room dead. It delivers a really nice performance. Then, you can tweak with levels etc and really get results. Correcting for peaks before correcting the room may reduce the peak, but cause other issues in that band.
No offense to anyone, but proprietary usually means "how I use a stock item" or intellectual property. I don't share my crossover designs - that's what really makes my speakers work. All of Brians parts were readily available - the magic was in how he made it all work.
There are several notable exceptions with exclusivity - the EMIM from Infinity, Magnepan, Martin Logan etc.
Using an electronic crossover with amps for each driver will offer the greatest performance upgrade. Crossover slopes get tricky. 6 db crossovers are very smooth, but blur imaging and specificity. They are wonderful sounding, a bit lush... 24db crossovers, on the other hand, are also phase correct, and allow each driver to perform to its best. The imaging SNAPS into place. Dynamics improve as well.
There's a reason for the 24/12 design. By dropping off the panel low end, it gets less fussy. It can perform better in its optimal range. Rolling off the woofer at 12, gives a fullness in the higher frequencies that the panel can't do.
As a general note, mixing crossover slopes requires a skilled hand, and in general, it's a nightmare. Most of my designs are 18db/oct and 24db/oct depending on the demand of the application.
Why 220? Well, contrary to so much forum chat, planar devices have limits. Dragoslav designed this driver - originally intended for a desk top speaker. It wasn't intended to be played loud - do he quoted a low frequency cutoff. In real world speakers for 89 db playback the crossover had to be thought out.
Now, planar types are easy to design down to 1000 hz. As you go down to 800, 500, 300, 150 it gets dramatically more complicated and you have to move more and more air. Pricing also increases the same. There's a reason Magnapans are so large - A large panel with little excursion is needed to equal the volume of displacement of a 10 or 12" woofer.
The BG Neo 8 is happy to about 800, the Neo 10 is good to about 300, unless you do an array and are good with cabinet geometry. And then you still only get to about 150. SO, yes, the VMPS panel can go low - but 220 is about the lowest with a 24db crossover that will really make it sing with less distortion and a tone more dynamics.
Oh, sorry - I've rambled again. Hope I didn't piss anyone off. It's important to remember, that I hold Brian in high esteem, and enjoyed his products. He was ahead of his time. If he were still alive, I like to think he would have created some OEM planars. Costs have gone down. Ah, in the next life...
