Jump to: navigation, search

Sounds.Earth (former CC-Zero-Project) is the digitization project of the Musical Heritage Organization.

Digitization and Records Cleaning

Cleaning of 78 rpm Gramophone records and Vinyl with the Keith Monks Dual-RCM Gemini MK III. Digitization with the ELP Laser turntable LT-2XA and the Numark TTX turntable.

14037188613 8b15982118 o.jpg


Carl has collected hundreds of music books during his music studies. Most important are the Encyclopedic Discographies of each Record label, mainly written and illustrated from other music historians and collectors. Biographies of music authors are published in the New Grove Dicitonary of Music and Musicians, the Musik in Geschichte und Gegenwart and Wikpedia. For US authors we have to check the status in the Catalog of Copyright Entries published by the US Copyright Office.



Sounds.Earth is continuing the idea behind the Public Domain Project in 2009. Do not waste time and money in the inventory and cataloging. It's a learning by doing concept:

  • Inspection of material to digitize that could be in the public domain
  • Enter the information from the record inside a database (we are planning our own Wikidata instance)
  • Cleaning the record with a RCM (Record Cleaning Machine)
  • Selection of the correct equalizer setting of the 78 rpm grammophone record
  • Digitization of the record
  • Reduce the metadata information fields to a minimum
  • Check the copyright status
  • Upload the audio file (24-Bit, 192 kHz, FLAC) to Wikimedia Commons good documented with references

Wikimedia Commons Upload statistics

  • Uploads for the Public Domain Project until 2018
  • Uploads for the CC-Zero-Project (2020-2021) and for Sounds.Earth from 2022

Continous Workflow

Carl has been specialized in the digitization and rightsclearing of historical audio documents since the new millenium. The processes and procedures have been continuously improved through his daily work. It is very difficult to find sponsors and at the same time to provide a continous workflow of high-quality digitized audio files with error-free metadata fields, well-documented informations about the 78 rpm records and finally the rightsclearing with irrefutable evidence that the recording is actually in the public domain.


Sounds.Earth is using three different phono preamplifiers. This means that the audio signals can be processed in the best possible quality by taking the correct equalizer setting. Acoustic and electrical recordings before 1925 had no cutting characteristics. Smaller labels only began to standardize their recordings in the mid-of the 1930s. Before the introduction of the RIAA equalization in 1955 there was no standardization. There was wild growth.


Metrics and Reports