It was later refined and expanded by Phil Sobel (May 13, 1917 – September 14, 2008), a prominent first chair woodwind player in the NBC staff orchestra and the leader of the West Coast Saxophone Quartet.
Sobel, who studied under Lindeman from 1935 to 1946, played a significant role in advancing and popularizing this method.
The Lindeman-Sobel Approach seeks to create an awareness in the individual of how their sound is being played rhythmically relative to the resistance of the tube length and the notes on the page.
"When you hold a note too long, it causes you to miss your next entrance, and consequently, you may rush to make up for the lost time.
"It's not about keeping up with the metronome (or the beat), it's about playing the correct mathematical combinations and always moving forward and going somewhere!"
Without rhythm to coordinate the air, tongue, embouchure, slide, fingers, bow, etc.