The imaginary part of the acoustic propagation constant. The commonly used unit is the radian per second or unit distance.
"I traveled the US and over seas with my show group and made several recordings during the 60s and 70s. I went through some of those 45records and they just were not playable due to being moved around. I really wanted to put them on cds for my kids and sent them to a couple of studios with very little luck i decided to send them to CVC and what ..."