Understanding Matrices: What Does MPO Mean?

MPO stands for Moulages et Plastiques de l’Ouest (Western Plastics Castings) a French pressing plant located in Averton, France. Founded in 1957, MPO has become one of the most renowned pressing and mastering plants globally, known for producing high-quality vinyl records. 

We see many records pressed by MPO, from a huge number of artists including Steve Vai, Cocteau Twins, The Smiths, Depeche Mode.

At time of writing, MPO has an extraordinary 85,974 credits on Discogs! They are still actively pressing/mastering releases, including modern reissues of classic artists like Mike Oldfield and Antonio Carlos Jobim.

The easiest route to recognising an MPO pressed or mastered record will be the presence of "MPO" etched into the vinyl matrix, between the end of the last track and the label.

Another route to recognising an MPO pressing is the 'pressing rings' on the label. A pressing ring is a circular indentation or ridge visible on the label area of a vinyl record. It is a physical mark left by the machinery used during the record's pressing process. The size, depth, and location of the pressing ring are determined by the specific pressing plant's equipment.

When it comes to MPO, their pressing rings vary by era, but generally, pre-1984 they had a single ring around the spindle hole. From 1984, their pressings increasingly had three rings around the spindle hole. 

If a release has 'MPO' in the matrices but the pressing rings differ from the above, it means it was mastered by them, but pressed by someone else.

This 1988 Cocteau Twins LP features 'JA MPO' etched into the matrices, which tells us the lacquer was cut by British mastering engineer Jack Adams, and pressed by MPO.

Another record pressed in 1988, this release by The Sugarcubes features the three concentric pressings rings we mentioned previously.

A UK release that was made in France, this 1984 Metallica album features 'MPO MFN 27 A¹ TY' in the A side matrices. MFN 27 is the catalogue number of the record, and 'TY' refers to Tim Young, who mastered/cut the record. Learn more about catalogue numbers.