|Thiele M5 tube microphone|
Here’s a scan of a short advertising document for Thiele M4 and M5 (photo to the left) tube microphones.
|Theile sales document|
Note how expensive the microphones were at the time - 500 and 600 Deutchmarks. For reference, between 1950 and 1960, 4 Deutchmarks approximately equalled 1 US dollar.