Pasted from the two first lines of your marketing information on M149 tube; 'The M 149 Tube is a variable dual-diaphragm microphone. The K 49 capsule ? well-known from the legendary U 47 and M 49 microphones' With a closer study of facts, this statement tells just a part of the true story. In the document 'Overview ov microphones and capsules built by Neumann Berlin' Issued by Georg Neumann GmbH Berlin 1999 you can find that U47 was built 1949-1965 and M49 was built 1951-1974. U47 had M7 capsules 1949-1960 and K 49 to 1960-1965 and M49 had M7 1951-1960 and 1960-1974 K49. These figures indicated that the majority of U47 and M49 was equipped with M7 capsules. M7 is a capsule with a PVC polyvinylchloride membran and K49 has a membran made of polyester PE. The manufacturing method differ quite much between these capsules and the audio qualities are also different. My opininon is that the very good reputation of U47 and M49 is very much based upon the M7 capsule and not the K 49.