I always loved the sound of the small planers. In my teens (70s) I had a pair of speakers the had a Heil Air Motion Transformer. Not quite a planer but lots of the same qualities). Then had some Infinity monitors with their EMIT tweeter. Moved up to a used set of the Infinity 2.5s. Much the same OB design as these speakers. They had two EMIMs mid range drivers open front and back. Two EMIT tweeters, one firing front the other to the rear. Bi-amped to a Walux sp? dual voice coil woofer. This was 35 years ago! A speaker ahead of its time? I got rid of them when the woofer surrounds fell apart. Wife, kids , work and years later I now would like to build/have sound something like these. I now just need to please the other, style wise. I will take a look at the monitors.