Lacquer Discs: A Race Against Time

Regarding the digitization of discs, the curators furthermore share:

Starting in the 1930s until roughly the 1950s, lacquer discs, also referred to as transcription discs or acetate discs (though the latter is a misnomer) were used widely for cutting masters in recording studios, in documenting radio broadcasts and creating instantaneous home recordings.

The discs consist of a substrate typically made of aluminum (occasionally glass or cardboard) with a nitrocellulose lacquer coating. Over time, the castor oil in the lacquer begins to leach out and a white powdery substance (palmitic acid) surfaces on the disc. Once this occurs, playback becomes increasingly problematic and the quality of the recording can be compromised as the disc has begun to show signs of deterioration. Proper cleaning and preservation of the recording is essential to prevent further damage and digitization at this late stage, although not without risks, is thankfully still possible. In time, the lacquer can further deteriorate and eventually delaminate, making the disc unplayable and its contents lost to history.

Lacquer discs are commonly found in sound recording archives, and their preservation is at a crucial moment in time – worldwide efforts are made to digitize recordings found on these analog carriers to ensure that the sounds captured therein remain accessible for future generations.

The Ethel Stark Collection contains a total of 44 lacquer discs showcasing Ethel Stark’s work as a soloist as well as a conductor with the Montreal Women’s Symphony Orchestra, the CBC Orchestra and the Toronto Symphony Orchestra. The recordings also feature an interview with Stark on Radio-Canada, and miscellaneous home and broadcast recordings.

In keeping with archival best practices, each record was inspected, cleaned either manually or by using a record cleaning machine. The discs were then digitized using a Rek-O-Kut turntable, Stanton 500 cartridge, various elliptical Rek-O-Kut archival styli, KAB EQS MK12 remastering phono preamp, and a Focusrite Scarlett 2i2 interface.

The resulting digital files are raw archival masters made for preservation purposes, without additional treatment (digital restoration, mixing, mastering). Artifacts are therefore present from the discs: pops, crackles, hisses and hums are a normal part of the carriers and the digitization process. And just like many archival record collections, they present a wide range of sonic quality (sometimes originating from the initial recording, sometimes due to deterioration of the physical materials), but all thankfully carried forward in digital form.