The two saxophonists Philipp Gerschlauer and Gebhard Ullmann deal in detail with the realm of microtones on "Twelve + 1 Murals". The common musical interests of Gerschlauer and Ullmann led to a collaboration that began a few years ago, however was slightly slowed down by Corona. "For me, Philipp is one of the best alto saxophonists in Berlin," Ullmann states enthusiastically about his co-musician. "During the first Covid year we tried out microphones and positions to achieve an optimal recording result for a saxophone duo." Thus an album was produced, and when mastering the sound engineer said: 'This is one of the best recordings I ever heard'.