Ruud, or Rudy as we called him, was my first teacher at the Royal Conservatory in The Hague. I knew nothing about jazz at the time. The first tune he taught me was Old Folks, which remains one of my favorite ballads today. I remember him playing a Jack Teagarden record of the song and playing along with it. I thought he sounded wonderful. He was a great player on both clarinet and tenor (he sang very nicely too). The best way for me to learn from him was to ask him to play some stuff over a tune and record that. I would transcribe at home what he had played.
He was very modest about his own playing, but he loved to tell a story about him and Getz: Once Rudy was playing at the North Sea Jazz Festival, when Getz entered the room. After listening to a tune or two Getz commented to whoever was with him: "I guess we're not the only dixieland band in town." Rudy was very proud of that story.
He passed away in the early nineties after he had been my teacher for little over a year.