What technique did Belgian composer Adrian Willaert popularize at St. Mark's Basilica?

*cori spezzati* (split choirs).

A significant moment in musical spatialization occurred in the mid-1500s with the technique known as *cori spezzati*, which translates to split choirs. Adrian Willaert, serving as the musical director at St. Mark's Basilica in Venice, was instrumental in popularizing this method. He exploited the church's existing architectural feature of dual organ placements to create a complex, alternating lattice of sound that enveloped the congregation. This required careful harmonic planning so that each separate singing or instrumental group was harmonically complete on its own, producing an effective spatial soundscape regardless of where an individual listener was seated within the basilica.