Audio CD questions 4440

Thanks for the addition. Digital transfer is loss-less, of course; perhaps what he was asking was "... by using different methods of compression would there be a loss of fidelity." In any event, fidelity is not a problem when making archive copies of early medium.

When I do a recovery and archive for one of my clients, I will always make at least two tracks of the original. One track is the pure, raw playback and the other is a sonically cleaned version with appropriate notations.

For example, I restored a unique single-side 78 rpm disc produced in 1919 featuring "The Dixis Jbutt Band" (sic - "Jbutt" was the original spelling of the early Jazz bands, since the word "Jazz" was Negro slang for loveual intercourse). There was a crack running from edge to label and a half-moon shaped piece approximately 1" deep by 2" long at the edge. The disc was playable from the margin of the missing piece into the recovery groove at the label, although the crack made an awful sound. Of course, the record had been played so many times that using a 50x stereo macro-scope on the grooves revealed that some spots were practically smooth.

Anyway, I produced the straight copy and then used software on the BeOS box to clean noise and the crack-induced pop. Then I played the disc using a piece of another single side disc taped from the reverse side into the missing section. I had ground the piece using a Dremel burr to fit the half-moon shape. After recording through that and capturing that data, I removed the non-topic audio fragment and subsbreastuted audio from the good grooves of the first 1" of the disc. I sbreastched all of that together an the museum now has the complete audio recording. The disc is back in the vault since it is -- to the best of anyone's knowledge truly unique.

The cost of this job if it had not been done on a volunteer basis would have been about $5,000.

We did a similar job on an Edison Amberol cylinder of the Fisk University Jubilee Singers which they recording in 1905.

The early styli (needles) were many times made from cactus needles and did minimal damage to the soft grooves. Later wind-up players used steel styli, which of course are a historical disaster.

If you ever visit Nevada, there is an early phonograph museum in Silver City that is worth the trip to see and receive the walk-through briefing by the archivist.

You'all come to Nashville, TN and the Country Music Hall of Fame and you can actually watch some of this recovery work in progress.

HTH,

Dave

Jeremiah DeWitt Weiner