Bit of an odd coupling, but read on

https://www.analogplanet.com/content...fried-linkwitz

Sadly it appears Linkwitz is having serious health issues. He's a huge inspiration for me an other speaker designers (see Comments). He is the Linkwitz in the linkwitz-Riley crossovers used in countless speakers and a long time proponent in designing polar patterns to use the room as a positive rather than negative as is typical with traditional designs.

cheers,

AJ