Bang & Olufsen Beomic?

Does anyone have some info regarding the sound quality from the good looking microphones produced by the Danish Bang & Olufsen in the sixties?

I don't think they were sold as professional microphones, rather some kind of consumer-grade. Is that correct?

Some of them are ribbon microphones.

interesting stuff at Stephen Sanks website
http://www.thuntek.net/~bk11/micdocs.htm
look at these threads
http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&threadm=3D4AFB7E.6F19564C%40caltech.edu&rnum=2&prev=/groups%3Fhl%3Den%26ie%3DUTF-8%26q%3Dbang%2Band%2Bolufsen%2Bmicrophone%26spell%3D1
http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&threadm=20030210151615.27993.00000638%40mb-ml.aol.com&rnum=1&prev=/groups%3Fhl%3Den%26lr%3D%26ie%3DUTF-8%26q%3Dbeomic