The Waffle House index has been measuring the impact of disasters in the USA since 2011: Green = full menu - restaurant has full power, food unlimited, damage at worst limited.

Yellow = limited menu - no power, food availability is limited. Red = restaurant closed - serious damage or flooding.

Translated to the free-spirited jazz rock of the band Kuhn Fu: the music on the new album Katastrofik Kink Machine jumps back and forth between green and red with enthusiasm and verve, leaving out the tepid middle.

There is something old-fashioned about the word jazz rock: music in which soulless virtuosity has replaced spirit and immediacy.

However, the guitarist and composer Christian Achim Kühn plays jazz fevered by electric guitar with his band Kuhn Fu, in which the joy of playing and the fun of profound nonsense (and then also: the virtuosity) oozes out of every pore.

Not least fun in the extreme: green and red, no yellow.