Jef is a Dutch pianist mainly known for his improvisations based on famous pop and rock songs. Even though he was classically trained he doesn’t follow the rules set by academics.
“To improvise implies you're forced to be naked. You can't hide behind safe rules. You're free to fly. But always aware that you could fall.”
Next to his improvisations based on famous themes you can also listen to his own compositions. You can find examples of these compositions on his last three albums In de Spiegel (2013), September (2017) and 'Elegy' (2019).