Direct metal mastering

Direct metal mastering (DMM) is an analog audio disc mastering technique jointly developed by two German companies, Telefunken-Decca (Teldec) and Georg Neumann GmbH, toward the end of the 20th century after having seen the same technology used by RCA Princeton Labs for its SelectaVision videodiscs in the late-1970s.

Records manufactured with this technology are often marked by a "DMM" logo on the outer record sleeve. Many current production high quality pressings, as well as standard production LPs from the 1990s, only indicate its use by inscribing "DMM" in the lead-out groove area of the disc.

Neumann was responsible for manufacturing the actual DMM cutting equipment as part of its VMS80 series lathes.