RCA 77-B1 Cardioid Ribbon Microphone #90888 (Vintage)

Vintage broadcast microphone in custom "Japan Black" paint. Great on vocals.

A ribbon mic works by suspending a thin piece of corrugated aluminum, (the 'ribbon'), between two poles of an Alnico magnet. The compression and rarefaction of air vibrates this ribbon in the magnetic field, which creates voltage changes that are run through an output transformer to the external amplifier of your choice. Like a dynamic mic, a ribbon requires no tubes, batteries or power supply of any kind. In the case of the RCA 77-B1, the chassis is built to absorb mechanical shocks, the output transformer is shielded against magnetic fields, and the capsule is resistant to changes in humidity and temperature.

The 77-B1 is a high-fidelity ribbon mic that was originally designed for both television and broadcast studio use.

The 77-B1 was the successor to the 77-A, and was advertised as a ‘unidirectional’ mic; its cardioid pattern effectively eliminating sound from the sides, and especially the rear of the microphone. One half of the ribbon acts as a velocity type mic, while the other half acts as a pressure type.

The RCA 77 series, which resembles a large pill of the capsule variety, has become THE iconic shape of a microphone, and remains so over 40 years after it was discontinued in 1967. The 77 Series was used in countless radio and TV studios in the 50s and 60s. Though rarely seen by the public, its excellent tone was certainly heard by millions, especially in the case of the most famous broadcaster of the period, Edward R. Murrow.