Karl Blau is a musician based in Anacortes, Washington and member of the Knw-Yr-Own/K Records collective. He is very prolific and releases music through a subscription service called Kelp Lunacy. He has played in D+, Brothers Blau, Captain Fathom, Your Heart Breaks and has collaborated extensively with Phil Elverum (The Microphones/Mount Eerie). He also tours and records with Laura Veirs.

Blau's music is eclectic and incorporates elements of folk, dub, R&B, bossanova, grunge, hiphop, drone, and worldbeat.

As of December 2007, a grass roots online petition drive has begun gathering signatures asking Knw-Yr-Own Records of Anacortes, Washington to reissue "Shell Collection", a compilation of early 4 track recordings by Karl Blau. On December 21st 2007, Karl Blau posted on his Myspace page "If the petition reaches 1,000 Karl Blau fans (Oh, gosh, are there that many?) that want to see the 4-track album "Shell Collection" on vinyl than Knw-Yr-Own will issue it on this format. Please sign the petition, everything sounds better on LP not to mention the art is bigger."