Recordz
What does DMM mean on a vinyl record?
DMM stands for Direct Metal Mastering, a way of cutting a record's master directly into a copper-coated disc instead of a soft lacquer. Developed in Germany by Teldec and Neumann and introduced in the early 1980s, it skips several steps of the usual plating process. Records made this way usually have "DMM" stamped or etched in the runout groove, and sometimes a DMM logo on the sleeve.
How a record is normally made
Most records start as a lacquer: an aluminum disc coated in soft nitrocellulose, cut on a lathe with a heated stylus. Because lacquer doesn't conduct electricity, it is sprayed with silver, then electroplated to make a negative metal "father". From the father comes a positive "mother", and from the mother come the negative "stampers" that press the vinyl. This is known as the three-step process.
Lacquers are fragile. The soft grooves can deform after cutting, so they are sent for plating as soon as possible.
How DMM is different
With DMM, a diamond stylus cuts the grooves into a thin layer of copper on a stainless steel disc. Copper is already conductive and rigid, so there is no silvering, and the copper master can serve as the mother. Stampers are plated straight from it. For large runs, plants may still grow extra generations from the copper disc.
Copper is much harder to cut than lacquer. A 1987 Audio magazine feature put it at five to ten times more resistant to the cutting stylus, which is why DMM used specially designed Neumann lathes. PS Audio's Copper magazine adds that the copper master is sturdy enough to be played back on a turntable, unlike a lacquer.
| Lacquer cutting | DMM | |
|---|---|---|
| Cutting surface | Nitrocellulose lacquer on aluminum | Copper on stainless steel |
| Silvering needed | Yes | No |
| Plating steps to a stamper | Three (father, mother, stamper) | One for small runs |
| Master durability | Fragile, used up in plating | Rigid metal |
What DMM changes in the sound
Supporters point to specific technical gains. Because copper doesn't spring back after cutting, there is less pre-echo, the faint ghost of a loud passage heard one revolution early. Skipping silvering also removes a step where dust can get trapped and add noise, a benefit the pressing plant Precision Pressing highlights in its guide.
Not everyone hears an improvement. Some listeners describe DMM pressings as harsh or forward in the treble. One explanation offered is the cutting angle: DMM cuts at close to vertical, about 5 degrees, while cartridges play back at the standard 20 degrees, so the system applies an electronic correction to the signal. How audible any of this is remains debated, and comparisons are hard because DMM and lacquer versions of the same album may differ in mastering too.
How to spot DMM in the runout
- Look in the dead wax for the letters "DMM" inscribed in the lead-out area alongside the other runout markings.
- Check the sleeve for a DMM logo or the words "Direct Metal Mastering". Some licensees not using the official DMM pressing profile used phrases like "Mastered on Copper" instead.
- Check the release on Discogs. Contributors credit the engineer as "Direct Metal Mastering By" and the studio as "Mastered At", rather than the "Lacquer Cut By" credit used for lacquers.
Wikipedia cites early-1980s pressings on Teldec in Germany and EMI in the UK as classic examples. Neumann built only about 30 DMM lathes, and in 2009 Wikipedia counted seven publicly available DMM cutting facilities, all in Germany, the Netherlands or the Czech Republic.
DMM FAQ
Is DMM better than lacquer?
Neither is universally better. DMM reduces pre-echo and avoids the noise silvering can add, while some listeners find DMM pressings brighter or harsher and prefer lacquer cuts.
When was DMM introduced?
Sources date it to the early 1980s, variously 1981, 1982 or 1983. It was developed by Teldec and Neumann, building on technology RCA developed for its SelectaVision videodisc.
Does a DMM record need a special turntable or stylus?
No. DMM records play on any standard turntable. The process includes correction so they track normally with ordinary cartridges.
Why does my record say DMM in the runout but not on the cover?
Wikipedia notes that many 1990s and later DMM pressings mark it only in the lead-out groove, not on the sleeve. The runout is the more reliable place to look.
Is DMM still used today?
Yes, though it is far less common than lacquer. Some pressing plants still offer it, but few cutting rooms have DMM lathes, and the remaining machines are kept running with salvaged parts since Neumann stopped making them.
Last updated September 30, 2026.
Sources: Direct metal mastering on Wikipedia; Precision Pressing: Guide to Direct Metal Mastering; Audio magazine, April 1987: Direct Metal Mastering; PS Audio Copper: The DMM dubplate; Third Man Pressing FAQ; Discogs Credits List.
