Direct Metal Mastering

Direct Metal Mastering requires a radically different cutting angle than traditional (lacquer) cutting, almost 0 degrees.

Direct Metal Mastering is a vinyl record manufacturing technology by TELDEC.

The actual stampers can be made either from normal acetates, or from a DMM disc (see Direct Metal Mastering).

A German invention called DMM (Direct Metal Mastering) has been used for some time in cutting conventional LP's.

These techniques, marketed as the CBS Laboratories and Teldec Direct Metal Mastering, were used to reduce inner-groove distortion.

In the early 1980's, in fact, the German company developed a new process, Direct Metal Mastering (DMM), which further refined LP sound and made longer sides possible.

As a result, some audio manufacturers today produce Phono Equalizers with selectable EQ curves, including options for Columbia, Decca, CCIR, and TELDEC's Direct Metal Mastering.

The Direct Metal Mastering technology addresses the lacquer mastering technology's issue of pre-echoes during record play, caused by the cutting stylus unintentionally transferring some of the subsequent groove wall's impulse signal into the previous groove wall.

Changes to master disc manufacturing methods, including the DMM or Direct Metal Mastering system, made it possible to make many copies of a master cut non-destructively, so a recut was no longer necessary when the plate used for pressing became worn.)

According to Bob Ludwig, the vice president and chief engineer at Masterdisk who mastered the Metallica LP, in the past two years a process called direct metal mastering has made it possible to cram more music onto an album side with less distortion or volume loss.

Even as its demise approached, however, the LP continued to develop, achieving longer playing time through Teldec's Direct Metal Mastering (the Harvard historian David S. Landes notes "a universal characteristic of once-dominant technologies: they make some of their greatest improvements under sentence of obsolescence").

A technological spin-off from the short-lived TED video system was Teldec's Direct Metal Mastering technology, called DMM, for the manufacturing of vinyl records: The cutting lathe engraves the audio signal groove directly into a copper-plated master disc, instead of a lacquer-plated aluminium disc.