Hi to All!
I will dare to recover this theme:
http://recforums.prosoundweb.com/index.php/mv/msg/11365/0/16/19109/Concerning condensers: I prefer to apply, as audio, film condensers. Our some domestic Hi-End - designers like to apply old kind Soviet paper/oil K40-U9 (К40-У9) and metall/paper OMBG (ОМБГ). In LOMO 19a19, in front of the transformer, paper MBM (МБМ) on 0.5uf, and between a capsule and a grid of a lamp the manufacturer puts the ceramic condenser.
Recently we have collected a microphone with clone cap K7 and transformer Bv8 from Oliver, by analogy with U47, but on octal a lamp 6J8 (6Ж8 ) and film condenser from anode to transformer on 2.2uf. Compared with new Telefunken Ela 251 and old U47 our microphone has acted very adequately.
I am sorry for my English.
Alexander Sonichev.