- IFO feat. Ralph Alessi: avant-garde project Identified Flying Object with Attila Gyárfás (drums) and Ralph Alessi (trumpet)
- Kimono Garden: electronics, vocals, synths and beats with Lorena del Mar (vocals), Mark Schilders (drums, guitars, synths) and Lennart Heyndels (bass, synths)
- Alex Koo Trio: piano trio with Dré Pallemaerts (drums) and Lennart Heyndels (double bass), frequently joined by Jean-Paul Estiévenart (trumpet)
- Alex Koo/Mark Turner/Ralph Alessi : acoustic chamber trio project from the album ‘Appleblueseagreen’ with Mark Turner (saxophone) and Ralph Alessi (trumpet)