From DB Mag, sometime mid seventies: a really fascinating discussion of something that I would have guessed was impossible: completely electro-mechanical automated audio time compression/expansion. As-in: changing the run time of an audio recording without changing the pitch. The article was written by one Sidney Silver, who was the recording/audio director of the telecom division of the UN. I feel like this could make an amazing-sounding plug-in if someone took the time to digitally model it.
Here is a June 1958 press announcement for Springer’s device, compete with photograph. The price in 1955 was $1900 ($14,000 in 2013 dollars) (SOURCE)
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