These would have been rim drive recorders, without a capstan drive roller. There is no fixed speed, it was determined by reel motor torque and the diameter of the amount of tape on either reel at any moment. Good luck with that, software is about your only available practical tool I know of..
From: Association for Recorded Sound Discussion List [mailto:[log in to unmask]] On Behalf Of J. D. Mack
Sent: Friday, July 12, 2019 1:30 PM
To: [log in to unmask]
Subject: [ARSCLIST] Reel-to-Reel tape problem
I'm looking for some advice/info. I sometimes transfer reel-to-reel tapes to CD or digital files for my customers. Frequently, I receive 3 inch tapes from the 1960s that start at one speed and gradually speed up or slow down substantially as the tape plays. The speed range is usually between 1 7/8 and 3 3/4, but never landing on either speed. I can correct for this using Adobe Audition's gliding stretch, but it takes quite a bit of trial and error. What sort of tape player would I need to hunt down to play these tapes correctly without having to resort to a software solution? My customers never have any idea what brand and model was used to make the recordings.