[1] With Jörgen Nilsson – and later Ulf Rådelius and Anders Lagerlöf – he formed the jazz group (Swedish) Nexus, which during its existence between 1972 and 1992 performed over 1000 concerts.

They made three highly accomplished records and performed on international jazz festivals, in radio and TV in several counties.

The piano style of Håkan Rydin has been described as "lyrical and cooking" and he has performed with Thad Jones, Pepper Adams, Red Mitchell, Etta Cameron, Enrico Rava, Tim Hagans, Georgie Fame, David Liebman and Swedish Jazz stars like Jan Allan, Arne Domnérus, Helge Albin, Anders Bergcrantz, Christer Boustedt, Bernt Rosengren and Svante Thuresson.

2010 he was the first jazz musician to perform in the Great Theatre (NCPA) in Beijing.

Rydin has published two books (in Swedish) on playing piano by ear, with colleague Dage Jonsson.