Turning Wax into Diamonds
December 1, 2023
Turning Wax into Diamonds: The Edison Diamond Disc Manufacturing Process (1920-1929)
by Robert Warren Apple, PhD Musicology
Around 1905, disc records and disc record players, such as Victor’s popular Victrola, began to grow in popularity and to take over the recording industry market, and by 1912, Edison’s greatest competitor, Columbia Records had completely given up producing cylinder records. Despite Edison’s personal preference for the cylinder record format, ensuring that Edison Records continued to produce cylinders until its dissolution in 1929, in 1911, the Edison Company unveiled its Edison Disc Phonograph that played the newly invented Diamond Discs to the public in an effort to stay relevant and competitive.
While contemporary listeners eventually recognized the superior durability and sound quality of the Diamond Disc format—so called because its players employed a diamond-tipped stylus that never wore out—when compared to the discs of Edison’s competitors, it took some time for the new format to catch on with the public. The acceptance of the new format was greatly hampered by a number of factors. The most important was that Edison Disc Phonographs could only play Diamond Discs and could not play the discs of other companies. This was because Diamond Disc groves were cut using the “hill and dale” method rather than the more common lateral cutting method employed by other companies, which meant that consumers would not be able to use their new Edison Disc Phonograph to play their old laterally cut records. Widespread adoption of the Diamond Disc was also curtailed by the fact that the outer surfaces of early Diamond Discs tended to separate from their inner cores making them unplayable and the sentiment among consumers that the early models of Edison Disc Phonograph cabinets were less esthetically pleasing than those of Victor’s Victrola line.
Things would gradually improve for the Edison Disc division thanks to its clever Tone Test marketing campaign. This campaign positioned audience members in front of a curtain and a live musician and Diamond Disc Phonograph on the other side, and then challenged the audience to try to tell the difference between the musician’s performance of a piece and a Diamond Disc recording of that same musician performing the same work. As planned, most audience members could not tell the difference between the two, thus bolstering the Edison Company’s claim that its Diamond Discs represented the superior audio format of the day. By 1920, the demand for new Diamond Disc records had grown so great that it reached its all-time high of around 7,721,080 records produced that year, and began to far outpace the company’s current Diamond Disc manufacturing process, which took about three weeks from when a new recording was cut to when Diamond Disc prints of it could be sold to the public. With this in mind, the engineer Paul B. Kasakove was brought on to develop a new Diamond Disc production process, which, according to the detailed description of the new method that he wrote on July 2, 1964, shortened the production of new Diamond Discs recordings to just three days.
This process began with the cutting of wax master records of three takes of a new recording at the Edison Company’s New York studio. In 1920, when this new process was put in effect, this was accomplished through acoustical means with the use of a recording horn, diaphragm, and cutting stylus that cut the grooves into wax masters, but in 1927, the Edison recording studios finally switched to electronic recording methods that employed microphones and amplifiers. Each of the three takes were given the same serial number followed by a letter; A, B, and C respectively. On the evening of the wax masters’ production, they were delivered to the company’s disc production plant in West Orange, New Jersey for the next step in the disc production process.
At the West Orange facility, these wax masters’ grooved surfaces were covered with graphite powder and electroplated with a layer of copper to create a negatively grooved copper master mold. When the layer of copper was thick enough, the copper master mold was separated from the wax master record and the wax master was then melted down to make new wax masters. The remaining copper master mold then had a copper lug soldered to the center of its ungrooved back before being sent to have its surface polished. A photograph of a polished copper master mold can be seen in Example 1.
Example 1: Polished grooved surface of a Diamond Disc copper master mold held at the Thomas Edison National Historical Park in Orange, New Jersey. Photograph reproduced here with the permission of the Thomas Edison National Historical Park.
The polished copper master mold’s surface was then electro-plated with nickel, followed by another round of copper electro-plating in order to produce a nickel second master record. After the final round of copper electro-plating, the nickel second master record was separated from the copper master mold using a special tool designed specifically for that purpose. A nickel second master record of an experimental Long Play Diamond Disc can be seen in Example 2.
Example 2: Front (shown left) and back (shown right) sides of a nickel second master record of an experimental Long Play Edison Diamond Disc (Serial Number: EXP. 98 C 150) recorded on April 1, 1927 at the Edison Record’s West Orange, New Jersey studio. On display at the Edison and Ford Winter Estates Museum.
The nickel second master record was then put through a similar electroplating process as the copper master mold in order to produce the nickel working molds (Example 3) that were employed along with the working molds of another recording to press the grooves onto both the right and left sides of Diamond Disc blanks, thus producing a complete double-sided Diamond Disc record (Example 4). One copper master mold could be used to produce up to 10 nickel second master records, and each second master record could in turn be employed to make up to a dozen nickel working molds that could be used to press hundreds of copies of a particular Diamond Disc side before they wore out, thus allowing for a much quicker and efficient method of mass producing Diamond Discs in order to meet increased demand.
Example 3. Front side of the nickel working mold used to press the “B” take of In Heavenly Love Abiding as recorded by the Metropolitan Quartet at the Edison Record’s New York, NY studio on January 28, 1919 onto the right side of copies of Diamond Disc (Label Number: 80462). On display at the Edison and Ford Winter Estates Museum.
Example 4. Right side of a copy of Diamond Disc (Label Number: 80465) which contains a recording of Mary Earl’s Beautiful Ohio as recorded by the Metropolitan Quartet on January 20, 1920 at the Edison Record’s New York, NY studio. Held in the Edison and Ford Winter Estates Object Collection.
While all of the wax masters of the three takes made of a particular recording were put through this process in order to produce at least one Diamond Disc record of each of the three takes, only one of the three takes would be selected by the Edison Record’s Music Committee, which included Thomas A. Edison himself, to go into full production. The copper masters of the two takes that were not chosen were once again put through the process of creating a nickel second master record, only this time each of these copper master molds and their respective newly created second master records were kept together and sealed inside of a solid copper case (Example 5) in order to protect the copper master mold of each take from being damaged or corroded by exposure to the air.
Example 5: Top of a copper master mold and its complimentary nickel second master record sealed inside of a solid copper case. Held at the Thomas Edison National Historical Park in Orange, New Jersey. Photograph reproduced here with the permission of the Thomas Edison National Historical Park.
As can be seen from the copper-plated backside of the unsealed Diamond Disc nickel second master record shown in Example 6, when exposed to the air, the copper surfaces of Diamond Disc copper master molds and nickel second master records can quickly acquire a layer of red and green corrosion, which, in the case of copper master molds, can completely destroy their grooves. The two unused takes’ pairs of sealed master mold and second master record where then kept in storage in a vault in case demand for a particular recording increased past the number of recordings that could be produced using just a single copper master mold or if anything went wrong in the Diamond Disc production process that damaged the copper master mold of take that was originally chosen by the Music Committee.
Example 6. Badly corroded copper-plated backside of an unsealed Diamond Disc nickel second master record used in the production of the “B” take of the Barcarolle from Jacques Offenbach’s opera Les contes d’Hoffman as recorded by Alice Verlet and Margarete Matzenauer on April 15, 1915 at the Edison Records New York, NY studio. Shown here behind wax paper and resting in its steel case. On display at the Edison and Ford Winter Estates Museum.
Around 1924, demand for new Edison Diamond Disc records began to drop precipitously triggering the Edison Company record division to begin working on new products to help them survive in the record marketplace. In October of 1926, the Edison Company introduce new 10- and 12-inch-long play Diamond Disc records that could play twelve minutes per side and twenty minutes per side respectively. In 1927, it began offering an attachment that allowed newer Diamond Disc Phonographs to play laterally cut discs. And in 1929, it introduced Edison Needle Records that were cut laterally like those of its competitors along with a portable needle disc player.
Despite these and other efforts, and with the coming of the financial crisis of the Great Depression, on October 28, 1929, the Edison Record division discontinued the production of all types of records, including Amberol cylinders, Diamond Discs, and Edison Needle Records. Even though the demand for new Diamond Discs was only a fraction of what it had been at its height in 1920, Kasakove’s manufacturing method held strong and was still being employed to produce Diamond Discs until the bitter end in 1929, and, as evidenced by a surviving unsealed Edison Needle Record copper master mold on display at the Edison and Ford Winter Estate’s Museum (Example 7), a similar method of production appears to have been used to make the short-lived line of Edison Needle Records.
Example 7. Back (shown left) and wax-paper-covered front (shown right) sides of the unsealed copper master mold (Serial Number: N-884 A) of the “A” take of the unissued Edison Needle Record recording of Ermine Calloway performing Let’s Get Acquainted recorded on May 8, 1929 at the Edison Record’s New York, NY studio. On display at the Edison and Ford Winter Estates Museum.
