Author: Jim Meade, Audio preservation engineer
Date: 11/02/2023

The Belfer Audio Lab’s contribution to the cylinder project came in two stages:

Our approach was based on our successful Latin American 45 digitization project, leveraging careful prep and research work into an efficient and robust workflow.

Research and prep

The project began with research and planning from early August to late September 2022.  

  • Gathered data from archived cylinder transfer worksheets spanning a ten-year period, entering stylus choice data into an XL spreadsheet sorted by label and ranked by frequency of use. This rendered a database of practical stylus choice ranges by label, based on engineering experience and our available selection of styli.
  • Made microscopic examinations and images of all styli identified in the spreadsheet to establish and record stylus condition.
  • Consulted archived correspondence with Expert Stylus UK to decode stylus names from the Expert Stylus UK order forms into actual stylus sizes.
  • Collaborated with the conservation librarian to determine acclimatization parameters. Logged environmental data from the preservation studio, comparing it to logger data from the cylinder storage areas on Belfer 2nd Determined the range of temperature coefficient required of acclimatization containers to be 5⁰F over 24hrs.
  • Corresponded with LOC and took acclimatization and equipment recommendations based on research by the LOC Preservation Research & Testing Division. This resulted in the purchase of two specified coolers and a pneumatic tire mail cart for cylinder transport to and from storage.
  • Collaborated with conservation librarian to manufacture custom waffle grids for cooler interiors (two tiered) to take 30 cylinders at a time for transport/acclimatization.
  • Evaluated Belfer’s two Archeophone machines for serviceability by A/B testing. Following a Zoom consultation with Archeophone design engineer Henri Chamoux in Paris, we optimized one machine by utilizing parts from its twin. We ordered parts for the second machine to assure redundancy on the project.
  • Evaluated the Archeophone signal chain, comprising:
    • Shure M44-7 cartridge with Expert Stylus custom styli
    • Vadlyd MD12 MkIII preamp
    • Benchmark ADC16 analog to digital converter
    • Lynx AES16e digital interface
    • Steinberg Wavelab software
    • Benchmark DAC1 digital to analog converter for audio monitoring.

This array of audio tools yielded a -130dBFS noise floor. Monitor routing was handled by a Crookwood C4 monitoring system.



  • Designed digitization workflow, production documentation, and metrics:
    • Transport and documentation of cylinders to and from climate-controlled storage, observing established acclimatization criteria.
    • Cleaning, repair, and conservation of cylinders prior to playback.
    • Stylus choice through data-driven reference to prior transfer work, as well as microscopic examination.
    • Digitization sequenced and recorded per collection inventory.
  • Digitization commenced in late Sept 2022.
  • Lab productivity averaged 60% above IASA throughput estimates throughout the project.
  • Digitization was completed on schedule in Sept 2023 with the transfer of 2575 cylinders.  


Thanks to:

Colleagues at other institutions generously gave of their time and expertise through technical consultations: Melissa Widzinski and Bryan Hoffa, audio preservation specialists at Library of Congress, noted early recording expert, Grammy winner and nine-time Grammy nominee David Giovannoni, and Larry Miller of Library of Congress. Also invaluable was the technical assistance of Henri Chamoux, inventor of the Archeophone cylinder player and a recognized expert in the digitization of sound archives.