matrix numbers on jamaican vinyl

since more and more jamaican single and maxi records get added, many people are getting confused about the nature of matrix numbers.

they are NOT catalogue numbers as some use to believe. they identify the stamper, not the release as such. however they are of great importance to identify different pressings. they should be added in note, optimally quoting the whole runout groove, like done for example here: http://www.discogs.com/release/587027.

below you will find a useful text on jamaican matrix numbers, posted at http://www.bloodandfire.co.uk/db/viewtopic.php?t=21898

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This is from RKR, Bob wrote it.

Matrix Numbers in Depth

Matrix numbers are a simple, coded method used by a pressing plant to identify the records manufactured by that factory. The numbers assigned to a specific title are either hand-etched or die-stamped directly into the metal parts that are used to press the record. A better understanding of the matrix number system used for both Jamaican and UK releases can provide collectors with a more complete picture of the production side of almost any record or series of records. Roots Knotty Roots documents the Jamaican matrix numbers and UK label number. UK records also have matrix numbers but label numbers easily identify the vast majority of UK pressings, so that is not an issue. Our research is focused primarily on the original Jamaican records because they are the first release and both stampers and label numbers with very few exceptions confirm that fact.

Jamaican record labels however, can be very deceptive, even misleading and often cannot be used to identify a particular title or artist credit. For example, some tunes were clearly popular enough to require more than one pressing, and sometimes the labels are different from one to the next. The simple explanation is that sometimes a particular ink or paper might be exhausted or unavailable, forcing the use of substitute materials. Furthermore, Jamaican labels occasionally give erroneous artist and title credits. Nice as is to own or examine a clean label copy of a record, for the purpose of identification nothing is more important than the stamper number and this is particularly true for the many blanks and pre-release labels that so often are the only copies found.

Because the matrix numbers are etched or stamped into the metal parts actually used to press the record (called "stampers") it cannot be changed or altered except by the effects of physical damage to the vinyl copy. In some instances matrix numbers can be difficult to read, but to the extent that they are read and interpreted correctly the stamper number is the only truly infallible source of accurate information about a particular record. Labels may vary from pressing to pressing, but the stamper number is always represented in the matrix of the record and that number is the most reliable way to confirm a title.

When a matrix is read correctly, coded information contained there can be interpreted to answer to three key questions: the pressing plant, the producer and when the stamper was made. During any musical era in Jamaica, the vast majority of stampers made were cut at one of the 2-3 studios that offered that service at the time. The cutting lathes required to make a stamper is expensive and cost often forced small producers to manufacture their records in stages as funds allowed. This helps explain why using matrix numbers to date records is not a perfect accounting of the release date. This becomes most noticeable by the mid seventies when the number of new records from new artists, labels and producers increases dramatically. Often we can date the stamper correctly, but that doesn’t really tell us when the record was pressed and distributed.

Unlike UK releases, the vast majority of Jamaican records that have a label are correctly identified on that label. For collectors, that reduces the problem of identification but does not entirely eliminate it due to the many pre release and blank label titles found. Despite the more professional graphics on UK labels, they actually contain much more erroneous information than the corresponding Jamaican label release. In the UK, titles were changed almost routinely and artist information or production credits are often wrong. These kinds of revisions inevitably make the discographer’s job more difficult, but fortunately we have one tool that can help resolve many disputed titles – the matrix number. Even when the label is unreliable or unavailable, the matrix or stamper number can often provide the most important missing details.

The matrix number is typically located in the empty space between the runoff grooves of the music and the label itself on every record manufactured. In Jamaica, each matrix number is composed of three key elements. First is the pressing plant itself (Wirl, Federal or Dynamic being the most common); second is the name of the producer, artist or company that ordered the metal stampers made and third is the numbers assigned to each title. These elements normally appear in the order described here and an example would be: Wirl PB 1919. This is a record pressed by Wirl (West Indies Records Ltd.) for Prince Buster in this instance, and assigned the title number 1919.

A file search for that matrix number reveals the title: "Too Hot" by Lee Perry & Prince Buster on the Olive Blossom label in 1967 – a good year for rocksteady. This example explains what these elements are and how they are combined in the Jamaican pressing plant system, but variations are common. The process of assigning the numeric code and etching or stamping the code into the metal parts used to press the records is done entirely by hand and prone to occasional error and even downright sloppy work. In Jamaica, new releases tended to come in waves or spikes that could be quite dramatic, pushing the limits of pressing plant capacity. Taking into account the myriad pressures and variable circumstances at work at any given time, the same matrix number shown above might also appear as Wirl 1919 PB or even as 1919 PB Wirl.

It makes no real difference what order these elements appear in; the specific meaning and significance remains the same. While many records display exceptions or variations to the typical order, knowing this may help readers understand why every matrix number in the Roots Knotty Roots DB may not be an absolute mirror of what appears on your copy of the same record. Sometimes when a key element was clearly left out, overlooked or miss-placed in a stamper, we have replaced it to maintain continuity for search and sort functions and to maintain continuity and consistency in dating titles. In other cases we have applied a consistent format to the matrix numbers even when the records do not.

Looking at other examples, we note that the way a producer is identified can vary widely from record to record or from one series of releases to the next. Federal stampers all have an F that precedes the producer’s initials. One example is FPB 6870 – "Trip To Mars" by The Skatalites on Buster’s Voice Of The People label. Similar variations include FB, FPB & FBR. These examples are all Federal stampers made for Prince Buster that show how a prefix to the title number is used within the Jamaican studio system. Producer credits may be written in various ways, but ultimately serve to simply identify who is the producer regardless of how that name may be written. Like so many aspects of Jamaican music, there are many various exceptions and anomalies to the way matrix numbers are used and many of these continue to reveal interesting stories ripe for further research.