Here's a snippet of just 1 of 125 oral history interviews that Steve Unkles of Audio-Visual Archives restored for the Springfield Armory in Springfield Massachusetts.  Here the recording was fair quality, where the restoration was a matter of isolating the voice and applying broad-band noise reductions.  The voice is certainly intelligible before processing, but the goal here was to optimize the audio quality for a more enjoyable and less fatiguing listening experience.  In the best cases, the on/off of the noise filtering that I include in this sample comparison will sound almost like a faucet being turned on and off during the recording with the voice unaffected.  Careful listening will reveal some artifacts of the filtering creeping in, but pretty good for a 15 or 20 minute procedure.

As for the content, these interviews are very interesting and reveal a lot about life during the build-up, War, and post-WWII years in America.  I think you'll get the gist of the sound comparison right away, but I had to run it long enough to tell this brief story.  The next sentence after this reveals that the pay rate was 35 cents an hour.

2-minute sound restoration sample from 10-30-84 interview

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