[Boatanchors] Do Headphones Age-Away?

[1oldlens1]

Here are two western electric patents issued to Halsey Fredrick for the very common WE magnetic type headphone.  These have both theory and a good deal of practical information on materials and dimensions   I got my antique Vaio going so can get to my archive drive.   I will also post (when I find it) the patent  for the famous Baldwin balanced armature headphone.  Btw these are very good but are very heavy.      Almost all magnetic phones are essentially like the Western Electric ones.Sent from my Galaxy