STC 4017C

The design originated from the Western Electric type 618A which was developed for WE by Bell Telephone labs. (circa 1931).

4017A denotes the first STC version of this microphone, which was supplied with an unreliable connector on the rear of the microphone. The 'C' revision in our collection has three screw terminals for Earth, positive and negative outputs.

We have also seen versions of the STC 4017C labelled 'Vitavox' and so has Martin Mitchell.

• Output impedance: 30 ohms
• Open-circuit level with pressure 1 microbar: -80 dB below 1 volt at 1 kHz
• The general level of output due to a sound field of pressure 1 bar will be -76 db with respect to 1 volt into 300 ohms load.

STC 4017C at The Coutant Website

STC 4017C at The Science Museum, UK

STC 4017C at Old BBC Radio Broadcasting

STC 4017C at Martin Mitchell's Microphone Blog