Sorry, I don't make "modern recorder"!
I must admit my aversion to mechanical solutions on the recorder as well as to the trumpet-like sound which often emanates from these instruments. The beauty and clean lines of the recorder with no mechanical devices and the purity and gentleness of its sound should not be sacrificed for few more decibels. However, there is no real impediment to the performance of contemporary music on the recorder. For example, I remember a friend, a student of Walter van Hauwe in Amsterdam, who used a A = 466 Hz Rafi tenor for a piece of contemporary music, specifically written for Walter. This piece was never performed before for the lack of a recorder with a range of three octaves. By a careful study of the Rafi instrument, my friend found fingerings for the notes of the chromatic third octave, and performed that piece using a copy of a sixteenth century recorder. Here is the table of the fingerings for the third register of the Rafi tenor.