From Steven Smolian: "...Ampexes would change speed to a noticable amount as
the weight of the tape
on one reel was shifted to the other..."
In this case it was wrong-diameter capstans. Columbia records had placed the
largest order for 300s up to that time and the machine shop in Chicago who
made the motor assemblies had farmed part of the job out to another shop in
order to meet the deadline. It hadn't occurred to anybody to double check
the assemblies or the speed of the machines. Shipping probably cost Ampex
most of their profit.
Bob Olhsson Audio Mastery, Nashville TN
Mastering, Audio for Picture, Mix Evaluation and Quality Control
Over 40 years making people sound better than they ever imagined!