On Monday, June 9, 2014 7:21:13 AM UTC-7, dave wrote:

I have some AR4x that appear to
have the original surrounds from ca 1968. All foam not created
equal. Refoaming is not difficult.
Are yours really foam? I have some AR-2ax's from the early 1907s, and the surrounds appear to be rubberized cloth (which should make a better seal than foam). They have survived over 30 years of California smog with no obvious degradation. I do not remember seeing foam on any of the old AR speakers (AR 1-4) I have seen at the swap meets.