Scott Hull on Vinyl, Part Eleven

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All About Deadwax and the Origins of the Independent Mastering Studio

Record Store Day may be past, but the vinyl keeps spinning. Welcome back for a “bonus round” of vinyl trivia! It’s time to talk about “deadwax.”


If you look at your records very closely you will see a variety of symbols cut into the lead-out or terminal groove. This area of the record is nicknamed the “deadwax.” The numbers in the deadwax go by a lot of different names. These are the main ones:

The Scribe Number: the cutting engineer uses a sharp pointed tool to cut the numbers and letters into the lacquer.

The Matrix Number: essentially a “part” number. It’s called “matrix” because the metal parts that are made at the plating plant are referred to as a matrix. It’s an older term from the molding industry.

The Catalog Number: reflecting the record label’s catalog system.

Other marks and symbols are sometimes in the lead out area of the disk. The technical ones can tell you a little something about the quality of the pressing. But to understand their significance you need to know a little more about the history of the mastering process.

Masterdisk Deadwax

In the 50’s and 60’s, lacquers cut for a major label project were cut by a technician. Literally he was a white-coat lab tech. They might not have known much about the music (of course some would have known more than others) but they weren’t there to change anything. Their job was to take the tape and cut it on the masterlacquer disk. Hence “mastering.”

If there was a technical problem, like the record skipped or distorted too much, they would either turn the level down or apply a filter to the highs or lows to allow the disk to be cut. Also during this early vinyl age, when an artist and producer went into the studio to record a song they could only hear the master when it was played in the studio. No one privately owned master playback decks — they were as large as a washing machine. A few people had low-speed 1/4″ analog tape decks at home, but for the most part they could only listen to their work when it was cut onto a lacquer.

Most recording studios and all labels had a mastering room. In the mastering room tapes from that day’s sessions would be transferred to record. These weren’t for mass production — they were take-home references. That was how the producer could listen to the final mix outside of the studio. That’s also how the label would hear the record. And the mastering engineers in these rooms, most of them anyway, were not known for taking extra care with these “dubs.” They were just like cassette copies, made so that the music could be more portable. Occasionally you will find some of these in the collectors market. They are often called acetates (though they stopped making them from acetate years prior).

But as the music business evolved an interesting thing happened. People began to notice that records cut by certain mastering engineers not only sounded better, but they were less likely to skip. And — most importantly — they SOLD more copies. So now not only did you need a great song, producer, band and studio, you needed a killer recording and mix engineer and the right mastering engineer, too.

This was truly the golden age of mastering. I got to see the last 10-12 years of it and it was remarkable. Independent mastering studios popped up in every major music market. And even though the major labels all had their own mastering studios and engineers, they would always send their important projects to Masterdisk, or Sterling Sound (both in NY), Kendun or The Mastering Lab (in LA) or other notable houses in Nashville, London, etc. Forgive me because I am leaving a lot of names out, but you get the idea that this new independent mastering business was off and running.

Album art for Sting Nothing Like the Sun

Some labels devoted enough resources to their engineering departments to make high quality cuts. CBS, A&M, Capitol, Atlantic and others had great engineers and some of the best equipment, but their livelihood rarely depended on being the BEST. Whereas the independent mastering engineer was constantly in competition for any new release. There even used to be “shoot-outs” (and still are, often). A record company or producer would make a few copies of the master tape and send one song to different mastering studios. When the different lacquers came back, they would then compare the results, and only one engineer would win the job. It wasn’t about price: they were looking for the sound.

Artists and producers would come from all over the globe to work with their favorite mastering engineer. My mentor, Bob Ludwig, had a very consistent relationship with Hugh Padgham from the UK. Hugh produced many wonderful recordings, but the projects I remember best records by The Police, Genesis, Sting and Phil Collins. The production team would finish their mixes in England and that night would fly “across the pond” on the Concorde. They would master their record with Bob that day, and that night, with reference disks in hand, they would return on the Concorde. Wow. And it had to be perfect.

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