The story
In the vacuum-tube era, Schoeps M 221-series microphones, especially the model M 221 B, were widely used in studios and for live orchestral recording. Their circuitry is based on the Telefunken AC 701k vacuum tube. They were introduced in 1954 and manufactured until the 1970s; many are still in use today.
One particular model of Schoeps microphone created for French radio (the CMT 20 series, 1964) has the historical distinction of being the first phantom-powered condenser microphone on the studio market.
From Wikipedia’s article on Schoeps, shared under CC BY-SA 4.0.5