Collecting guides
Matrix Numbers… What the Runout Says, and What It Doesn't
Read the matrix numbers and other marks near a record’s label, compare pressing candidates, and know when an identification needs more evidence.
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The small writing near a record’s label was put there for the people making it. Collectors arrived later, with lamps.
A matrix number identifies manufacturing parts used to make the record. It often resembles the catalogue number with a side letter or number added. Sometimes it does not. There is no single code that explains every record on your shelf.
First, know where you are looking
The runout, also called the dead wax, is the band between the last music groove and the label. It can contain the matrix number, a mastering engineer’s initials, a plant mark and other symbols. They share the space; they do not all mean the same thing.
Some matrix numbers are also printed on the paper label. Note those separately. A label matrix and an inscription in the runout are different observations, even when the characters agree.
Read what is there
Stamped characters tend to look regular; hand-etched ones look like someone wrote them. Record that distinction when it helps separate candidates. It is a clue, not a verdict on its own.
- Hold the record by its edges under a lamp to the side. Slowly tilt it until the marks catch the light.
- Work around the whole band. Numbers and other marks may be far apart.
- Copy both sides exactly, including letters and symbols. Mark uncertain characters as uncertain. A photo or magnifier may help.
- Keep the side and location clear in your notes. Discogs asks for a complete runout string per side, with single spaces between separated groups.
There is no prize for reading it in one glance. Change the angle before deciding a faint character must be an 8.
Use it to separate candidates
Start with the sleeve and label. If two editions still look alike, compare their documented runouts with your copy. Our pressing identification guide walks through those earlier checks.
A different inscription does not automatically mean a different release. Discogs can list several runout variants under one release. Check the whole entry and what the difference represents, rather than treating an extra hyphen as a discovery.
Keep the useful uncertainty
Read both sides. Keep engineer marks separate from your interpretation of the matrix. Do not turn a copyright date, a familiar number or a hopeful guess into proof of an edition.
Sometimes the marks settle it. Sometimes they leave two plausible candidates. Save what you can see and note what would distinguish them. Kura can help you organise the collection; the evidence still lives on the record.