Theodor Lotz (1747-1792) was an instrument maker living in Vienna at the same time as Mozart. He can be associated directly with Anton Stadler, Mozart's first clarinettist. Unfortunately only one clarinet of Lotz has survived (Genève 136), together with a number of his bassethorns. Several instruments of contemporary instrument makers like Griesbacher and Hammig have remained.
My Lotz-clarinets are mostly based on the b flat clarinet that is kept in Gen¸ve, but I also studied the instruments of his collegues (e.g. a clarinet in A that is in Leipzig). These instrument have a rather wide bore and the finger holes are positioned rather low, especially those for the right hand. These low (and therefore somewhat larger) holes contribute to the rich sound. The Lotz instruments I build are clarinets with five keys, which are very suitable for the music of Mozart and contemporaries. To facilitate the playing of music from later times, I also make parts with extra keys.